Search Results

Search found 6500 results on 260 pages for 'dave white'.

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

Page 27/260 | < Previous Page | 23 24 25 26 27 28 29 30 31 32 33 34  | Next Page >

  • Are there white lists for Yahoo, Gmail, Hotmail and AOL?

    - by Waleed Eissa
    In my website (under development), the members can send messages to each other which are sent directly to their email, now I'm worried that some members can send spam to other members (I have a spam filter but it doesn't give 100% protection as you know), I'm worried that my domain might get blacklisted on Yahoo, Gmail, Hotmail or AOL which will cause any messages sent from my domain to end up in the spam folder, this is why I want to add the domain of my website to their whitelists (if they exist). P.S. I don't want to use private messages that members check on the site and I have my reason for this. Thanks

    Read the article

  • Google maps not showing satellite background - streets on white background.

    - by WooYek
    Custom map is broken on satellite view, does not show satellite imagery. Any ideas, what's wrong? Overlays are also broken - they're not transparent. Code: <div id="map_canvas" class="grid_8 omega" style="width:460px; height: 420px"></div> <script src="http://maps.google.com/maps?file=api&amp;v=3&amp;sensor=true&amp;key=my-key-is-here" type="text/javascript"></script> <script type="text/javascript"> function initialize() { if (GBrowserIsCompatible()) { var map = new GMap2(document.getElementById("map_canvas")); map.setCenter(new GLatLng(52.229676, 21.012229), 13); map.setMapType(G_HYBRID_MAP); map.setUIToDefault(); } var geocoder = new GClientGeocoder(); function showAddress(address) { geocoder.getLatLng(address, function(point) { if (!point) { alert('Nie mozna znalezc adresu: '+address); } else { map.setCenter(point, 13); var marker = new GMarker(point); map.addOverlay(marker); marker.openInfoWindowHtml(address); } } ); } showAddress('some address goes here') } $('body').ready(initialize); $('body').unload(GUnload); </script>

    Read the article

  • css/html: white space break fix and now cant code fine?

    - by Karem
    Yes, so I got the problem that if you type a long sentence with no space e.g eeeeeeeeeeeeeeeeeeeeeeee, it will break itself, but then now I would need to start typing some ugly non-breaking coding. Example: http://jsfiddle.net/r3CFJ/ I need to have everything in one sentence in order not to make it break itself. Check here to see the result of not having everything in one sentence: http://jsfiddle.net/r3CFJ/1/ How can I fix this please any solutions?? as my further coding will get very ugly and not readable?

    Read the article

  • How to get rid of white space between css horizontal list items?

    - by Curyous
    I've got the following test page and css. When displayed, there is a 4px gap between each list item. How do I get the items to be next to each other? <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Frameset//EN" "http://www.w3.org/TR/html4/frameset.dtd"> <html> <head> <link type="text/css" rel="stylesheet" href="/stylesheets/test.css" /> </head> <body> <div> <ul class="nav"> <li class="nav"><a class="nav" href="#">One1</a></li> <li class="nav"><a class="nav" href="#">Two</a></li> <li class="nav"><a class="nav" href="#">Three</a></li> <li class="nav"><a class="nav" href="#">Four</a></li> </ul> </div> </body> </html> The css: ul.nav, ul li.nav { display: inline; margin: 0px; padding: 0px; } ul.nav { list-style-type: none; } li.nav { background-color: red; } a.nav { background-color: green; padding: 10px; margin: 0px; } a:hover.nav { background-color: gray; }

    Read the article

  • White-box testing in Javascript - how to deal with privacy?

    - by Max Shawabkeh
    I'm writing unit tests for a module in a small Javascript application. In order to keep the interface clean, some of the implementation details are closed over by an anonymous function (the usual JS pattern for privacy). However, while testing I need to access/mock/verify the private parts. Most of the tests I've written previously have been in Python, where there are no real private variables (members, identifiers, whatever you want to call them). One simply suggests privacy via a leading underscore for the users, and freely ignores it while testing the code. In statically typed OO languages I suppose one could make private members accessible to tests by converting them to be protected and subclassing the object to be tested. In Javascript, the latter doesn't apply, while the former seems like bad practice. I could always wall back to black box testing and simply check the final results. It's the simplest and cleanest approach, but unfortunately not really detailed enough for my needs. So, is there a standard way of keeping variables private while still retaining some backdoors for testing in Javascript?

    Read the article

  • XNA 4.0 SpriteBatch.Draw Out Of Memory Exception Thrown

    - by RustyGearGames
    Well, first of all, my guess is that I'm calling the spritebatch.draw() method to many times, but I need to (Or, it's the only way I can figure out how to) Draw my in-game windows. I'll just go ahead and dump my code; using System; using System.Text; using System.Collections.Generic; using System.Linq; using Microsoft.Xna.Framework; using Microsoft.Xna.Framework.Audio; using Microsoft.Xna.Framework.Content; using Microsoft.Xna.Framework.GamerServices; using Microsoft.Xna.Framework.Graphics; using Microsoft.Xna.Framework.Input; using Microsoft.Xna.Framework.Media; namespace System.Window { class Window { #region Variables public Texture2D importedTexture; public Texture2D WindowSkin; public RenderTarget2D currentWindow; public RenderTarget2D windowTexture; public Vector2 pos; public int prevWindowWidth; public int prevWindowHeight; public int windowWidth; public int windowHeight; public bool visible; public bool active; public bool drawNew; #region Rectangles public Rectangle clickRect; public Rectangle topLeftRect; public Rectangle topRightRect; public Rectangle buttonRect; public Rectangle botLeftRect; public Rectangle botRightRect; #endregion #endregion public Window() { } public void Initialize(GraphicsDevice g, Texture2D ws, Texture2D it, int w, int h, bool v, bool a) { WindowSkin = ws; importedTexture = it; windowWidth = w; prevWindowWidth = w; windowHeight = h; prevWindowHeight = h; windowTexture = new RenderTarget2D(g, windowWidth, windowHeight); currentWindow = windowTexture; visible = v; active = a; drawNew = true; topLeftRect = new Rectangle(0, 0, 32, 32); topRightRect = new Rectangle(32, 0, 32, 32); buttonRect = new Rectangle(64, 0, 32, 32); botLeftRect = new Rectangle(0, 64, 32, 32); botRightRect = new Rectangle(64, 64, 32, 32); } public void Update(GraphicsDevice g, Vector2 p, int width, int height) { prevWindowWidth = windowWidth; prevWindowHeight = windowHeight; pos = p; windowWidth = width; windowHeight = height; windowTexture = new RenderTarget2D(g, windowWidth+2, windowHeight+2); } public void Draw(SpriteBatch s, GraphicsDevice g) { s.Draw(currentWindow, pos, new Rectangle(0, 0, windowWidth, windowHeight), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); } public void DrawNewWindow(SpriteBatch s, GraphicsDevice g) { g.SetRenderTarget(windowTexture); g.Clear(Color.Transparent); s.Begin(); #region Draw Background for (int w = 3; w < (windowWidth); w += 32) { for (int h = 32; h < (windowHeight); h += 32) { s.Draw(WindowSkin, new Vector2(w, h), new Rectangle(32, 32, 32, 32), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); } } #endregion s.Draw(importedTexture, new Vector2(3, 32), new Rectangle(0, 0, importedTexture.Width, importedTexture.Height), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); #region Draw resizables for (int i = 32; i < (windowWidth - 64); i += 32) { s.Draw(WindowSkin, new Vector2(i, 0), new Rectangle(16, 0, 32, 32), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); } for (int i = 32; i < (windowWidth - 32); i += 32) { s.Draw(WindowSkin, new Vector2(i, windowHeight - 32), new Rectangle(32, 64, 32, 32), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); } for (int i = 64; i < (windowHeight - 32); i += 32) { s.Draw(WindowSkin, new Vector2(0, i), new Rectangle(0, 48, 32, 32), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); } for (int i = 64; i < (windowHeight - 32); i += 32) { s.Draw(WindowSkin, new Vector2(windowWidth - 32, i), new Rectangle(64, 48, 32, 32), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); } #endregion #region Draw Corners s.Draw(WindowSkin, new Vector2(0, 0), topLeftRect, Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); s.Draw(WindowSkin, new Vector2(0, 32), new Rectangle(0, 32, 32, 32), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); s.Draw(WindowSkin, new Vector2(windowWidth - 64, 0), topRightRect, Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); s.Draw(WindowSkin, new Vector2(windowWidth - 32, 32), new Rectangle(64, 32, 32, 32), Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); s.Draw(WindowSkin, new Vector2(windowWidth - 32, 0), buttonRect, Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); s.Draw(WindowSkin, new Vector2(0, windowHeight - 32), botLeftRect, Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); s.Draw(WindowSkin, new Vector2(windowWidth - 32, windowHeight - 32), botRightRect, Color.White, 0, Vector2.Zero, 1.0f, SpriteEffects.None, 0); #endregion s.End(); currentWindow = windowTexture; } } } It's all nice and configured for my little windowskin texture, and such. the only problem is that it will get a little laggy, and then completely crash on me about a minute into running it. It throws an Out Of Memory Exception, but I don't know and can't find any other topic or post on this relating to spritebatch. Does anybody have any suggestions on how I can get this working and not take up much memory? I would think this as an easy, cost effective way of drawing a window. I'm just not sure how cut down on my draw calls, or get any of that memory back.

    Read the article

  • ASP.NET Web API Exception Handling

    - by Fredrik N
    When I talk about exceptions in my product team I often talk about two kind of exceptions, business and critical exceptions. Business exceptions are exceptions thrown based on “business rules”, for example if you aren’t allowed to do a purchase. Business exceptions in most case aren’t important to log into a log file, they can directly be shown to the user. An example of a business exception could be "DeniedToPurchaseException”, or some validation exceptions such as “FirstNameIsMissingException” etc. Critical Exceptions are all other kind of exceptions such as the SQL server is down etc. Those kind of exception message need to be logged and should not reach the user, because they can contain information that can be harmful if it reach out to wrong kind of users. I often distinguish business exceptions from critical exceptions by creating a base class called BusinessException, then in my error handling code I catch on the type BusinessException and all other exceptions will be handled as critical exceptions. This blog post will be about different ways to handle exceptions and how Business and Critical Exceptions could be handled. Web API and Exceptions the basics When an exception is thrown in a ApiController a response message will be returned with a status code set to 500 and a response formatted by the formatters based on the “Accept” or “Content-Type” HTTP header, for example JSON or XML. Here is an example:   public IEnumerable<string> Get() { throw new ApplicationException("Error!!!!!"); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The response message will be: HTTP/1.1 500 Internal Server Error Content-Length: 860 Content-Type: application/json; charset=utf-8 { "ExceptionType":"System.ApplicationException","Message":"Error!!!!!","StackTrace":" at ..."} .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The stack trace will be returned to the client, this is because of making it easier to debug. Be careful so you don’t leak out some sensitive information to the client. So as long as you are developing your API, this is not harmful. In a production environment it can be better to log exceptions and return a user friendly exception instead of the original exception. There is a specific exception shipped with ASP.NET Web API that will not use the formatters based on the “Accept” or “Content-Type” HTTP header, it is the exception is the HttpResponseException class. Here is an example where the HttpReponseExcetpion is used: // GET api/values [ExceptionHandling] public IEnumerable<string> Get() { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError)); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The response will not contain any content, only header information and the status code based on the HttpStatusCode passed as an argument to the HttpResponseMessage. Because the HttpResponsException takes a HttpResponseMessage as an argument, we can give the response a content: public IEnumerable<string> Get() { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("My Error Message"), ReasonPhrase = "Critical Exception" }); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The code above will have the following response:   HTTP/1.1 500 Critical Exception Content-Length: 5 Content-Type: text/plain; charset=utf-8 My Error Message .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The Content property of the HttpResponseMessage doesn’t need to be just plain text, it can also be other formats, for example JSON, XML etc. By using the HttpResponseException we can for example catch an exception and throw a user friendly exception instead: public IEnumerable<string> Get() { try { DoSomething(); return new string[] { "value1", "value2" }; } catch (Exception e) { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("An error occurred, please try again or contact the administrator."), ReasonPhrase = "Critical Exception" }); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Adding a try catch to every ApiController methods will only end in duplication of code, by using a custom ExceptionFilterAttribute or our own custom ApiController base class we can reduce code duplicationof code and also have a more general exception handler for our ApiControllers . By creating a custom ApiController’s and override the ExecuteAsync method, we can add a try catch around the base.ExecuteAsync method, but I prefer to skip the creation of a own custom ApiController, better to use a solution that require few files to be modified. The ExceptionFilterAttribute has a OnException method that we can override and add our exception handling. Here is an example: using System; using System.Diagnostics; using System.Net; using System.Net.Http; using System.Web.Http; using System.Web.Http.Filters; public class ExceptionHandlingAttribute : ExceptionFilterAttribute { public override void OnException(HttpActionExecutedContext context) { if (context.Exception is BusinessException) { throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(context.Exception.Message), ReasonPhrase = "Exception" }); } //Log Critical errors Debug.WriteLine(context.Exception); throw new HttpResponseException(new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent("An error occurred, please try again or contact the administrator."), ReasonPhrase = "Critical Exception" }); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: Something to have in mind is that the ExceptionFilterAttribute will be ignored if the ApiController action method throws a HttpResponseException. The code above will always make sure a HttpResponseExceptions will be returned, it will also make sure the critical exceptions will show a more user friendly message. The OnException method can also be used to log exceptions. By using a ExceptionFilterAttribute the Get() method in the previous example can now look like this: public IEnumerable<string> Get() { DoSomething(); return new string[] { "value1", "value2" }; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } To use the an ExceptionFilterAttribute, we can for example add the ExceptionFilterAttribute to our ApiControllers methods or to the ApiController class definition, or register it globally for all ApiControllers. You can read more about is here. Note: If something goes wrong in the ExceptionFilterAttribute and an exception is thrown that is not of type HttpResponseException, a formatted exception will be thrown with stack trace etc to the client. How about using a custom IHttpActionInvoker? We can create our own IHTTPActionInvoker and add Exception handling to the invoker. The IHttpActionInvoker will be used to invoke the ApiController’s ExecuteAsync method. Here is an example where the default IHttpActionInvoker, ApiControllerActionInvoker, is used to add exception handling: public class MyApiControllerActionInvoker : ApiControllerActionInvoker { public override Task<HttpResponseMessage> InvokeActionAsync(HttpActionContext actionContext, System.Threading.CancellationToken cancellationToken) { var result = base.InvokeActionAsync(actionContext, cancellationToken); if (result.Exception != null && result.Exception.GetBaseException() != null) { var baseException = result.Exception.GetBaseException(); if (baseException is BusinessException) { return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(baseException.Message), ReasonPhrase = "Error" }); } else { //Log critical error Debug.WriteLine(baseException); return Task.Run<HttpResponseMessage>(() => new HttpResponseMessage(HttpStatusCode.InternalServerError) { Content = new StringContent(baseException.Message), ReasonPhrase = "Critical Error" }); } } return result; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } You can register the IHttpActionInvoker with your own IoC to resolve the MyApiContollerActionInvoker, or add it in the Global.asax: GlobalConfiguration.Configuration.Services.Remove(typeof(IHttpActionInvoker), GlobalConfiguration.Configuration.Services.GetActionInvoker()); GlobalConfiguration.Configuration.Services.Add(typeof(IHttpActionInvoker), new MyApiControllerActionInvoker()); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   How about using a Message Handler for Exception Handling? By creating a custom Message Handler, we can handle error after the ApiController and the ExceptionFilterAttribute is invoked and in that way create a global exception handler, BUT, the only thing we can take a look at is the HttpResponseMessage, we can’t add a try catch around the Message Handler’s SendAsync method. The last Message Handler that will be used in the Wep API pipe-line is the HttpControllerDispatcher and this Message Handler is added to the HttpServer in an early stage. The HttpControllerDispatcher will use the IHttpActionInvoker to invoke the ApiController method. The HttpControllerDipatcher has a try catch that will turn ALL exceptions into a HttpResponseMessage, so that is the reason why a try catch around the SendAsync in a custom Message Handler want help us. If we create our own Host for the Wep API we could create our own custom HttpControllerDispatcher and add or exception handler to that class, but that would be little tricky but is possible. We can in a Message Handler take a look at the HttpResponseMessage’s IsSuccessStatusCode property to see if the request has failed and if we throw the HttpResponseException in our ApiControllers, we could use the HttpResponseException and give it a Reason Phrase and use that to identify business exceptions or critical exceptions. I wouldn’t add an exception handler into a Message Handler, instead I should use the ExceptionFilterAttribute and register it globally for all ApiControllers. BUT, now to another interesting issue. What will happen if we have a Message Handler that throws an exception?  Those exceptions will not be catch and handled by the ExceptionFilterAttribute. I found a  bug in my previews blog post about “Log message Request and Response in ASP.NET WebAPI” in the MessageHandler I use to log incoming and outgoing messages. Here is the code from my blog before I fixed the bug:   public abstract class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { var corrId = string.Format("{0}{1}", DateTime.Now.Ticks, Thread.CurrentThread.ManagedThreadId); var requestInfo = string.Format("{0} {1}", request.Method, request.RequestUri); var requestMessage = await request.Content.ReadAsByteArrayAsync(); await IncommingMessageAsync(corrId, requestInfo, requestMessage); var response = await base.SendAsync(request, cancellationToken); var responseMessage = await response.Content.ReadAsByteArrayAsync(); await OutgoingMessageAsync(corrId, requestInfo, responseMessage); return response; } protected abstract Task IncommingMessageAsync(string correlationId, string requestInfo, byte[] message); protected abstract Task OutgoingMessageAsync(string correlationId, string requestInfo, byte[] message); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   If a ApiController throws a HttpResponseException, the Content property of the HttpResponseMessage from the SendAsync will be NULL. So a null reference exception is thrown within the MessageHandler. The yellow screen of death will be returned to the client, and the content is HTML and the Http status code is 500. The bug in the MessageHandler was solved by adding a check against the HttpResponseMessage’s IsSuccessStatusCode property: public abstract class MessageHandler : DelegatingHandler { protected override async Task<HttpResponseMessage> SendAsync(HttpRequestMessage request, CancellationToken cancellationToken) { var corrId = string.Format("{0}{1}", DateTime.Now.Ticks, Thread.CurrentThread.ManagedThreadId); var requestInfo = string.Format("{0} {1}", request.Method, request.RequestUri); var requestMessage = await request.Content.ReadAsByteArrayAsync(); await IncommingMessageAsync(corrId, requestInfo, requestMessage); var response = await base.SendAsync(request, cancellationToken); byte[] responseMessage; if (response.IsSuccessStatusCode) responseMessage = await response.Content.ReadAsByteArrayAsync(); else responseMessage = Encoding.UTF8.GetBytes(response.ReasonPhrase); await OutgoingMessageAsync(corrId, requestInfo, responseMessage); return response; } protected abstract Task IncommingMessageAsync(string correlationId, string requestInfo, byte[] message); protected abstract Task OutgoingMessageAsync(string correlationId, string requestInfo, byte[] message); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } If we don’t handle the exceptions that can occur in a custom Message Handler, we can have a hard time to find the problem causing the exception. The savior in this case is the Global.asax’s Application_Error: protected void Application_Error() { var exception = Server.GetLastError(); Debug.WriteLine(exception); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I would recommend you to add the Application_Error to the Global.asax and log all exceptions to make sure all kind of exception is handled. Summary There are different ways we could add Exception Handling to the Wep API, we can use a custom ApiController, ExceptionFilterAttribute, IHttpActionInvoker or Message Handler. The ExceptionFilterAttribute would be a good place to add a global exception handling, require very few modification, just register it globally for all ApiControllers, even the IHttpActionInvoker can be used to minimize the modifications of files. Adding the Application_Error to the global.asax is a good way to catch all unhandled exception that can occur, for example exception thrown in a Message Handler.   If you want to know when I have posted a blog post, you can follow me on twitter @fredrikn

    Read the article

  • Use Extension method to write cleaner code

    - by Fredrik N
    This blog post will show you step by step to refactoring some code to be more readable (at least what I think). Patrik Löwnedahl gave me some of the ideas when we where talking about making code much cleaner. The following is an simple application that will have a list of movies (Normal and Transfer). The task of the application is to calculate the total sum of each movie and also display the price of each movie. class Program { enum MovieType { Normal, Transfer } static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfNormalMovie = 0; int totalPriceOfTransferMovie = 0; foreach (var movie in movies) { if (movie == MovieType.Normal) { totalPriceOfNormalMovie += 2; Console.WriteLine("$2"); } else if (movie == MovieType.Transfer) { totalPriceOfTransferMovie += 3; Console.WriteLine("$3"); } } } private static IEnumerable<MovieType> GetMovies() { return new List<MovieType>() { MovieType.Normal, MovieType.Transfer, MovieType.Normal }; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } In the code above I’m using an enum, a good way to add types (isn’t it ;)). I also use one foreach loop to calculate the price, the loop has a condition statement to check what kind of movie is added to the list of movies. I want to reuse the foreach only to increase performance and let it do two things (isn’t that smart of me?! ;)). First of all I can admit, I’m not a big fan of enum. Enum often results in ugly condition statements and can be hard to maintain (if a new type is added we need to check all the code in our app to see if we use the enum somewhere else). I don’t often care about pre-optimizations when it comes to write code (of course I have performance in mind). I rather prefer to use two foreach to let them do one things instead of two. So based on what I don’t like and Martin Fowler’s Refactoring catalog, I’m going to refactoring this code to what I will call a more elegant and cleaner code. First of all I’m going to use Split Loop to make sure the foreach will do one thing not two, it will results in two foreach (Don’t care about performance here, if the results will results in bad performance, you can refactoring later, but computers are so fast to day, so iterating through a list is not often so time consuming.) Note: The foreach actually do four things, will come to is later. var movies = GetMovies(); int totalPriceOfNormalMovie = 0; int totalPriceOfTransferMovie = 0; foreach (var movie in movies) { if (movie == MovieType.Normal) { totalPriceOfNormalMovie += 2; Console.WriteLine("$2"); } } foreach (var movie in movies) { if (movie == MovieType.Transfer) { totalPriceOfTransferMovie += 3; Console.WriteLine("$3"); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } To remove the condition statement we can use the Where extension method added to the IEnumerable<T> and is located in the System.Linq namespace: foreach (var movie in movies.Where( m => m == MovieType.Normal)) { totalPriceOfNormalMovie += 2; Console.WriteLine("$2"); } foreach (var movie in movies.Where( m => m == MovieType.Transfer)) { totalPriceOfTransferMovie += 3; Console.WriteLine("$3"); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The above code will still do two things, calculate the total price, and display the price of the movie. I will not take care of it at the moment, instead I will focus on the enum and try to remove them. One way to remove enum is by using the Replace Conditional with Polymorphism. So I will create two classes, one base class called Movie, and one called MovieTransfer. The Movie class will have a property called Price, the Movie will now hold the price:   public class Movie { public virtual int Price { get { return 2; } } } public class MovieTransfer : Movie { public override int Price { get { return 3; } } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The following code has no enum and will use the new Movie classes instead: class Program { static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfNormalMovie = 0; int totalPriceOfTransferMovie = 0; foreach (var movie in movies.Where( m => m is Movie)) { totalPriceOfNormalMovie += movie.Price; Console.WriteLine(movie.Price); } foreach (var movie in movies.Where( m => m is MovieTransfer)) { totalPriceOfTransferMovie += movie.Price; Console.WriteLine(movie.Price); } } private static IEnumerable<Movie> GetMovies() { return new List<Movie>() { new Movie(), new MovieTransfer(), new Movie() }; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   If you take a look at the foreach now, you can see it still actually do two things, calculate the price and display the price. We can do some more refactoring here by using the Sum extension method to calculate the total price of the movies:   static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfNormalMovie = movies.Where(m => m is Movie) .Sum(m => m.Price); int totalPriceOfTransferMovie = movies.Where(m => m is MovieTransfer) .Sum(m => m.Price); foreach (var movie in movies.Where( m => m is Movie)) Console.WriteLine(movie.Price); foreach (var movie in movies.Where( m => m is MovieTransfer)) Console.WriteLine(movie.Price); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now when the Movie object will hold the price, there is no need to use two separate foreach to display the price of the movies in the list, so we can use only one instead: foreach (var movie in movies) Console.WriteLine(movie.Price); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } If we want to increase the Maintainability index we can use the Extract Method to move the Sum of the prices into two separate methods. The name of the method will explain what we are doing: static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfMovie = TotalPriceOfMovie(movies); int totalPriceOfTransferMovie = TotalPriceOfMovieTransfer(movies); foreach (var movie in movies) Console.WriteLine(movie.Price); } private static int TotalPriceOfMovieTransfer(IEnumerable<Movie> movies) { return movies.Where(m => m is MovieTransfer) .Sum(m => m.Price); } private static int TotalPriceOfMovie(IEnumerable<Movie> movies) { return movies.Where(m => m is Movie) .Sum(m => m.Price); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now to the last thing, I love the ForEach method of the List<T>, but the IEnumerable<T> doesn’t have it, so I created my own ForEach extension, here is the code of the ForEach extension method: public static class LoopExtensions { public static void ForEach<T>(this IEnumerable<T> values, Action<T> action) { Contract.Requires(values != null); Contract.Requires(action != null); foreach (var v in values) action(v); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I will now replace the foreach by using this ForEach method: static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfMovie = TotalPriceOfMovie(movies); int totalPriceOfTransferMovie = TotalPriceOfMovieTransfer(movies); movies.ForEach(m => Console.WriteLine(m.Price)); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } The ForEach on the movies will now display the price of the movie, but maybe we want to display the name of the movie etc, so we can use Extract Method by moving the lamdba expression into a method instead, and let the method explains what we are displaying: movies.ForEach(DisplayMovieInfo); private static void DisplayMovieInfo(Movie movie) { Console.WriteLine(movie.Price); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Now the refactoring is done! Here is the complete code:   class Program { static void Main(string[] args) { var movies = GetMovies(); int totalPriceOfMovie = TotalPriceOfMovie(movies); int totalPriceOfTransferMovie = TotalPriceOfMovieTransfer(movies); movies.ForEach(DisplayMovieInfo); } private static void DisplayMovieInfo(Movie movie) { Console.WriteLine(movie.Price); } private static int TotalPriceOfMovieTransfer(IEnumerable<Movie> movies) { return movies.Where(m => m is MovieTransfer) .Sum(m => m.Price); } private static int TotalPriceOfMovie(IEnumerable<Movie> movies) { return movies.Where(m => m is Movie) .Sum(m => m.Price); } private static IEnumerable<Movie> GetMovies() { return new List<Movie>() { new Movie(), new MovieTransfer(), new Movie() }; } } public class Movie { public virtual int Price { get { return 2; } } } public class MovieTransfer : Movie { public override int Price { get { return 3; } } } pulbic static class LoopExtensions { public static void ForEach<T>(this IEnumerable<T> values, Action<T> action) { Contract.Requires(values != null); Contract.Requires(action != null); foreach (var v in values) action(v); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } I think the new code is much cleaner than the first one, and I love the ForEach extension on the IEnumerable<T>, I can use it for different kind of things, for example: movies.Where(m => m is Movie) .ForEach(DoSomething); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } By using the Where and ForEach extension method, some if statements can be removed and will make the code much cleaner. But the beauty is in the eye of the beholder. What would you have done different, what do you think will make the first example in the blog post look much cleaner than my results, comments are welcome! If you want to know when I will publish a new blog post, you can follow me on twitter: http://www.twitter.com/fredrikn

    Read the article

  • The Select query I am using is not working.. Can Somebody Guide me to the Correct way?

    - by Parth
    I am using the Select query as SELECT id, ordering FROM `jos_menu` WHERE ordering='".$rec['ordering'] -'1' ."' AND parent = '0' Here I need all the records whose ordering is less than 1 of the selected record's order($rec['ordering'] = getting from other select query ) when I am trying to echo the query I am not getting complete statement but getting only this -1' AND parent = '0' here is the whole snippet $where = ' WHERE (id = ' . implode( ' OR id = ', $cid ) . ')';//Pranav Dave Coded echo $selquery = "SELECT id, ordering FROM `jos_menu`".$where; //Pranav Dave Coded $db->setQuery( $selquery );//Pranav Dave Coded $record = $db->loadAssocList(); //Pranav Dave Coded if ($model->orderItem($id, -1)) { echo "<pre>"; print_r($model); /*exit;*/ //echo $updorderup = mysql_escape_string($model->_db->_sql);//Pranav Dave Coded foreach($record as $rec)//Pranav Dave Coded { echo $aboverow = "SELECT id, ordering FROM `jos_menu` WHERE ordering='".$rec['ordering'] -'1' ."' AND parent = '0'"; $db->setQuery( $aboverow ); $above = $db->loadAssoc(); echo "<pre>"; print_r($above); }//end of foreach }//end of if Please suggest me where I am getting wrong.....

    Read the article

  • GD! Converting a png image to jpeg and making the alpha by default white and not black.

    - by Shawn
    I tried something like this but it just makes the background of the image white, not necessarily the alpha of the image. I wanted to just upload everything as jpg's so if i could somehow "flatten" a png image with some transparently to default it to just be white so i can use it as a jpg instead. Appreciate any help. Thanks. $old = imagecreatefrompng($upload); $background = imagecolorallocate($old,255,255,255); imagefill($old, 0, 0, $background); imagealphablending($old, false); imagesavealpha($old, true);

    Read the article

  • SQL SERVER – How to See Active SQL Server Connections For Database

    - by Pinal Dave
    Another question received via email - “How do I I know which user is connected to my database with how many connection?” Here is the script which will give us answer to the question. SELECT DB_NAME(dbid) AS DBName, COUNT(dbid) AS NumberOfConnections, loginame FROM    sys.sysprocesses GROUP BY dbid, loginame ORDER BY DB_NAME(dbid) Here is the resultset: Reference: Pinal Dave (http://blog.SQLAuthority.com)Filed under: PostADay, SQL, SQL Authority, SQL DMV, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

    Read the article

  • Silverlight Cream for April 07, 2010 -- #833

    - by Dave Campbell
    In this Issue: Alan Mendelevich, Siyamand Ayubi, Rudi Grobler(-2-), Josh Smith, VinitYadav, and Dave Campbell. Shoutouts: Jordan Knight has a demo up of a project he did for DigiGirlz: DigiGirlz, Deep Zoom and Azure, hopefully we'll get source later :) Jeremy Likness has a must-read post on his Ten Reasons to use the Managed Extensibility Framework I put this on another post earlier, but if you want some desktop bling for WP7, Ozymandias has some: I Love Windows Phone Wallpaper If you're not going to be in 'Vegas next week, Tim Heuer reminds us there's an alternative: Watch the Silverlight 4 Launch event and LIVE QA with ScottGu and others From SilverlightCream.com: Ghost Lines in Silverlight Alan Mendelevich reports an issue when drawing lines with odd coordinate values. He originated it in Silverlight 3, but it is there in SL4RC as well... check it out and leave him a comment. A Framework to Animate WPF and Silverlight Pages Similar to the PowerPoint Slides Siyamand Ayubi has an interesting post up on animating WPF or Silverlight pages to make them progress in the manner of a PPT slideshow. And it can also make phone calls… Rudi Grobler has a list of 'tasks' you can do with WP7 such as PhoneCallTask or EmailComposeTask ... looks like this should be plasticized :) Using the GPS, Accelerometer & Vibration Controller Rudi Grobler is also investigating how to use the GPS, Accelerometer, and Vibration in WP7 with a bunch of external links to back it up. Assembly-level initialization at design time Josh Smith has a solution to the problem of initializing design-time data in Blend (did you know that was an issue?) ... the solution is great and so is the running commentary between Josh and Karl Shifflett in the comments! ySurf : A Yahoo Messenger Clone built in Silverlight VinitYadav built a Yahoo Messenger app in Silverlight and has detailed out all the ugly bits for us on the post, plus made everything available. Your First Silverlight Application Dave Campbell's first post at DZone cracking open a beginner's series on Silverlight. If you're expecting something heavy-duty, skip this. If you're wanting to learn Silverlight and haven't jumped in yet, give it a try. Stay in the 'Light! Twitter SilverlightNews | Twitter WynApse | WynApse.com | Tagged Posts | SilverlightCream Join me @ SilverlightCream | Phoenix Silverlight User Group Technorati Tags: Silverlight    Silverlight 3    Silverlight 4    Windows Phone MIX10

    Read the article

  • SQLAuthority News – Presented Soft Skill Session on Presentation Skills at SQL Bangalore on May 3, 2014

    - by Pinal Dave
    I have presented on various database technologies for almost 10 years now. SQL, Database and NoSQL have been part of my life. Earlier this month, I had the opportunity to present on the topic Performing an Effective Presentation. I must say it was blast to prepare as well as present this session. This event was part of the SQL Bangalore community. If you are in Bangalore, you must be part of this group. SQL Bangalore is a wonderful community and we always have a great response when we present on technology. It is SQL User Group and we discuss everything SQL there. This month we had SQL Server 2014 theme and we had a community launch of SQL Server. We have the best of the best speakers presenting on SQL Server 2014 technology. The event had amazing speakers and each of them did justice to the subject. You can read about this over here. In this session I told a story from my life. I talked about who inspired me and how I learned to speak in public. I told stories about two legends  who have inspired me. There is no video recording of this session. If you want to get resources from this session, please sign up my newsletter at http://bit.ly/sqllearn. Well, I had a great time at this event. We had over 250 people showed up at this event and had a grand  time together. I personally enjoyed a session of Amit Benerjee, Balmukund Lakhani and Vinod Kumar. Ken and Surabh also entertained the audience. Overall, this was a grand event and if you were in Bangalore and did not make it to this event. You did miss out on a few things. Here are a few photos of this event. SQL Bangalore UG Nupur, Chandra, Shaivi, Balmukund, Amit, Vinod [captions This] SQL Bangalore UG Audience Pinal Dave presenting at SQL UG in Bangalore Here are few of the slides from this presentation: Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, SQLAuthority News, T SQL

    Read the article

  • SQL Saturday 194 - Exeter

    - by Dave Ballantyne
    Many kudos goes to Jonathan and Annette Allen and the others on the team for confirming SQL Saturday 194 in Exeter on the 8th and 9th of March.  The event home page is here http://www.sqlsaturday.com/194/eventhome.aspx and I delighted that myself and Dave Morrison will be presenting a full day pre-con on the 8th on favourite subjects “TSQL and Internals”. Here is the full abstract : TSQL and internals - When faced with performance issues there are many lines of attack. Tuning the engine itself can get you so far, however for maximum effect you need to understand how the engine and how it translates SQL statements into performable actions. This is not a simple task, it is a massive task to deal with a multi-table join and the number of permutations can be immense. To back up this knowledge, we can create better performing TSQL and understand the impact that is has upon the engine and recognize the pitfalls and gotcha’s that exist in SQLServer. Ultimately, there is no ‘best way’ to perform a single task only many variations of ‘it depends’ , but now we can pick the most appropriate option for the required dataload. Over the years, there have been many myths and misconceptions have grown around the product, some have basis in older versions and some are just wrong. Continuing to build on the knowledge given so far these issue will be explored and broken down and proved or disproved. Finally we will look to the future and explore SQL Server 2012 and the new functionality that that brings and some of the common uses that we will be able to address. After completion of this days pre-con, attendees will have a more complete knowledge of execution plans, and how they relate to the physical and logical actions that SQLServer will be executing on their behalf. The attendees will also have a more rounded and fuller knowledge of TSQL and the implications of incorrectly defining a query. Dave is a fountain of knowledge on execution plans and optimizer internals and ,though i may flatter myself, I’m no shrinking violet when it comes to TSQL and such matters.  I hope that if you cant join us, then there are other pre-cons available from other experts in their fields that may ‘float you boat’ too.  The pre-con page is http://sqlsouthwest.co.uk/SQLSaturday_precon.htm Also, excitingly, this pre-con day is sponsored by Fusion-IO which is a great boon for the day. If you want a more of this then i am offering a 2 day TSQL course starting on the 19th of March. More details on this are available here

    Read the article

  • Emacs/xterm color annoyance on Linux

    - by tgamblin
    I'm using emacs in a console window both on my local Linux box and on the login node of a remote cluster. I use emacs regularly, and I've got the foreground color set to white in my .emacs file like so: (set-foreground-color "white") (set-background-color "black") However, when I run emacs, the foreground isn't white; it's grey and very hard to read. On my Mac, emacs in a console window with the same settings shows up as proper white. But on both linux boxes, in konsole and xterm, it's grey. In case it matters, I've got TERM set to xterm-color, the desktop is running RHEL 5, and the cluster node is running RHEL 4 (CentOS). Is this some default with how Linux sets up terminal colors? How do I get white to be white? Note: this is with console emacs, not emacs under X. That's emacs -nw if you have DISPLAY set.

    Read the article

  • Hello Operator, My Switch Is Bored

    - by Paul White
    This is a post for T-SQL Tuesday #43 hosted by my good friend Rob Farley. The topic this month is Plan Operators. I haven’t taken part in T-SQL Tuesday before, but I do like to write about execution plans, so this seemed like a good time to start. This post is in two parts. The first part is primarily an excuse to use a pretty bad play on words in the title of this blog post (if you’re too young to know what a telephone operator or a switchboard is, I hate you). The second part of the post looks at an invisible query plan operator (so to speak). 1. My Switch Is Bored Allow me to present the rare and interesting execution plan operator, Switch: Books Online has this to say about Switch: Following that description, I had a go at producing a Fast Forward Cursor plan that used the TOP operator, but had no luck. That may be due to my lack of skill with cursors, I’m not too sure. The only application of Switch in SQL Server 2012 that I am familiar with requires a local partitioned view: CREATE TABLE dbo.T1 (c1 int NOT NULL CHECK (c1 BETWEEN 00 AND 24)); CREATE TABLE dbo.T2 (c1 int NOT NULL CHECK (c1 BETWEEN 25 AND 49)); CREATE TABLE dbo.T3 (c1 int NOT NULL CHECK (c1 BETWEEN 50 AND 74)); CREATE TABLE dbo.T4 (c1 int NOT NULL CHECK (c1 BETWEEN 75 AND 99)); GO CREATE VIEW V1 AS SELECT c1 FROM dbo.T1 UNION ALL SELECT c1 FROM dbo.T2 UNION ALL SELECT c1 FROM dbo.T3 UNION ALL SELECT c1 FROM dbo.T4; Not only that, but it needs an updatable local partitioned view. We’ll need some primary keys to meet that requirement: ALTER TABLE dbo.T1 ADD CONSTRAINT PK_T1 PRIMARY KEY (c1);   ALTER TABLE dbo.T2 ADD CONSTRAINT PK_T2 PRIMARY KEY (c1);   ALTER TABLE dbo.T3 ADD CONSTRAINT PK_T3 PRIMARY KEY (c1);   ALTER TABLE dbo.T4 ADD CONSTRAINT PK_T4 PRIMARY KEY (c1); We also need an INSERT statement that references the view. Even more specifically, to see a Switch operator, we need to perform a single-row insert (multi-row inserts use a different plan shape): INSERT dbo.V1 (c1) VALUES (1); And now…the execution plan: The Constant Scan manufactures a single row with no columns. The Compute Scalar works out which partition of the view the new value should go in. The Assert checks that the computed partition number is not null (if it is, an error is returned). The Nested Loops Join executes exactly once, with the partition id as an outer reference (correlated parameter). The Switch operator checks the value of the parameter and executes the corresponding input only. If the partition id is 0, the uppermost Clustered Index Insert is executed, adding a row to table T1. If the partition id is 1, the next lower Clustered Index Insert is executed, adding a row to table T2…and so on. In case you were wondering, here’s a query and execution plan for a multi-row insert to the view: INSERT dbo.V1 (c1) VALUES (1), (2); Yuck! An Eager Table Spool and four Filters! I prefer the Switch plan. My guess is that almost all the old strategies that used a Switch operator have been replaced over time, using things like a regular Concatenation Union All combined with Start-Up Filters on its inputs. Other new (relative to the Switch operator) features like table partitioning have specific execution plan support that doesn’t need the Switch operator either. This feels like a bit of a shame, but perhaps it is just nostalgia on my part, it’s hard to know. Please do let me know if you encounter a query that can still use the Switch operator in 2012 – it must be very bored if this is the only possible modern usage! 2. Invisible Plan Operators The second part of this post uses an example based on a question Dave Ballantyne asked using the SQL Sentry Plan Explorer plan upload facility. If you haven’t tried that yet, make sure you’re on the latest version of the (free) Plan Explorer software, and then click the Post to SQLPerformance.com button. That will create a site question with the query plan attached (which can be anonymized if the plan contains sensitive information). Aaron Bertrand and I keep a close eye on questions there, so if you have ever wanted to ask a query plan question of either of us, that’s a good way to do it. The problem The issue I want to talk about revolves around a query issued against a calendar table. The script below creates a simplified version and adds 100 years of per-day information to it: USE tempdb; GO CREATE TABLE dbo.Calendar ( dt date NOT NULL, isWeekday bit NOT NULL, theYear smallint NOT NULL,   CONSTRAINT PK__dbo_Calendar_dt PRIMARY KEY CLUSTERED (dt) ); GO -- Monday is the first day of the week for me SET DATEFIRST 1;   -- Add 100 years of data INSERT dbo.Calendar WITH (TABLOCKX) (dt, isWeekday, theYear) SELECT CA.dt, isWeekday = CASE WHEN DATEPART(WEEKDAY, CA.dt) IN (6, 7) THEN 0 ELSE 1 END, theYear = YEAR(CA.dt) FROM Sandpit.dbo.Numbers AS N CROSS APPLY ( VALUES (DATEADD(DAY, N.n - 1, CONVERT(date, '01 Jan 2000', 113))) ) AS CA (dt) WHERE N.n BETWEEN 1 AND 36525; The following query counts the number of weekend days in 2013: SELECT Days = COUNT_BIG(*) FROM dbo.Calendar AS C WHERE theYear = 2013 AND isWeekday = 0; It returns the correct result (104) using the following execution plan: The query optimizer has managed to estimate the number of rows returned from the table exactly, based purely on the default statistics created separately on the two columns referenced in the query’s WHERE clause. (Well, almost exactly, the unrounded estimate is 104.289 rows.) There is already an invisible operator in this query plan – a Filter operator used to apply the WHERE clause predicates. We can see it by re-running the query with the enormously useful (but undocumented) trace flag 9130 enabled: Now we can see the full picture. The whole table is scanned, returning all 36,525 rows, before the Filter narrows that down to just the 104 we want. Without the trace flag, the Filter is incorporated in the Clustered Index Scan as a residual predicate. It is a little bit more efficient than using a separate operator, but residual predicates are still something you will want to avoid where possible. The estimates are still spot on though: Anyway, looking to improve the performance of this query, Dave added the following filtered index to the Calendar table: CREATE NONCLUSTERED INDEX Weekends ON dbo.Calendar(theYear) WHERE isWeekday = 0; The original query now produces a much more efficient plan: Unfortunately, the estimated number of rows produced by the seek is now wrong (365 instead of 104): What’s going on? The estimate was spot on before we added the index! Explanation You might want to grab a coffee for this bit. Using another trace flag or two (8606 and 8612) we can see that the cardinality estimates were exactly right initially: The highlighted information shows the initial cardinality estimates for the base table (36,525 rows), the result of applying the two relational selects in our WHERE clause (104 rows), and after performing the COUNT_BIG(*) group by aggregate (1 row). All of these are correct, but that was before cost-based optimization got involved :) Cost-based optimization When cost-based optimization starts up, the logical tree above is copied into a structure (the ‘memo’) that has one group per logical operation (roughly speaking). The logical read of the base table (LogOp_Get) ends up in group 7; the two predicates (LogOp_Select) end up in group 8 (with the details of the selections in subgroups 0-6). These two groups still have the correct cardinalities as trace flag 8608 output (initial memo contents) shows: During cost-based optimization, a rule called SelToIdxStrategy runs on group 8. It’s job is to match logical selections to indexable expressions (SARGs). It successfully matches the selections (theYear = 2013, is Weekday = 0) to the filtered index, and writes a new alternative into the memo structure. The new alternative is entered into group 8 as option 1 (option 0 was the original LogOp_Select): The new alternative is to do nothing (PhyOp_NOP = no operation), but to instead follow the new logical instructions listed below the NOP. The LogOp_GetIdx (full read of an index) goes into group 21, and the LogOp_SelectIdx (selection on an index) is placed in group 22, operating on the result of group 21. The definition of the comparison ‘the Year = 2013’ (ScaOp_Comp downwards) was already present in the memo starting at group 2, so no new memo groups are created for that. New Cardinality Estimates The new memo groups require two new cardinality estimates to be derived. First, LogOp_Idx (full read of the index) gets a predicted cardinality of 10,436. This number comes from the filtered index statistics: DBCC SHOW_STATISTICS (Calendar, Weekends) WITH STAT_HEADER; The second new cardinality derivation is for the LogOp_SelectIdx applying the predicate (theYear = 2013). To get a number for this, the cardinality estimator uses statistics for the column ‘theYear’, producing an estimate of 365 rows (there are 365 days in 2013!): DBCC SHOW_STATISTICS (Calendar, theYear) WITH HISTOGRAM; This is where the mistake happens. Cardinality estimation should have used the filtered index statistics here, to get an estimate of 104 rows: DBCC SHOW_STATISTICS (Calendar, Weekends) WITH HISTOGRAM; Unfortunately, the logic has lost sight of the link between the read of the filtered index (LogOp_GetIdx) in group 22, and the selection on that index (LogOp_SelectIdx) that it is deriving a cardinality estimate for, in group 21. The correct cardinality estimate (104 rows) is still present in the memo, attached to group 8, but that group now has a PhyOp_NOP implementation. Skipping over the rest of cost-based optimization (in a belated attempt at brevity) we can see the optimizer’s final output using trace flag 8607: This output shows the (incorrect, but understandable) 365 row estimate for the index range operation, and the correct 104 estimate still attached to its PhyOp_NOP. This tree still has to go through a few post-optimizer rewrites and ‘copy out’ from the memo structure into a tree suitable for the execution engine. One step in this process removes PhyOp_NOP, discarding its 104-row cardinality estimate as it does so. To finish this section on a more positive note, consider what happens if we add an OVER clause to the query aggregate. This isn’t intended to be a ‘fix’ of any sort, I just want to show you that the 104 estimate can survive and be used if later cardinality estimation needs it: SELECT Days = COUNT_BIG(*) OVER () FROM dbo.Calendar AS C WHERE theYear = 2013 AND isWeekday = 0; The estimated execution plan is: Note the 365 estimate at the Index Seek, but the 104 lives again at the Segment! We can imagine the lost predicate ‘isWeekday = 0’ as sitting between the seek and the segment in an invisible Filter operator that drops the estimate from 365 to 104. Even though the NOP group is removed after optimization (so we don’t see it in the execution plan) bear in mind that all cost-based choices were made with the 104-row memo group present, so although things look a bit odd, it shouldn’t affect the optimizer’s plan selection. I should also mention that we can work around the estimation issue by including the index’s filtering columns in the index key: CREATE NONCLUSTERED INDEX Weekends ON dbo.Calendar(theYear, isWeekday) WHERE isWeekday = 0 WITH (DROP_EXISTING = ON); There are some downsides to doing this, including that changes to the isWeekday column may now require Halloween Protection, but that is unlikely to be a big problem for a static calendar table ;)  With the updated index in place, the original query produces an execution plan with the correct cardinality estimation showing at the Index Seek: That’s all for today, remember to let me know about any Switch plans you come across on a modern instance of SQL Server! Finally, here are some other posts of mine that cover other plan operators: Segment and Sequence Project Common Subexpression Spools Why Plan Operators Run Backwards Row Goals and the Top Operator Hash Match Flow Distinct Top N Sort Index Spools and Page Splits Singleton and Range Seeks Bitmaps Hash Join Performance Compute Scalar © 2013 Paul White – All Rights Reserved Twitter: @SQL_Kiwi

    Read the article

  • SQL SERVER – Microsoft SQL Server 2014 CTP1 Product Guide

    - by Pinal Dave
    Today in User Group meeting there were lots of questions related to SQL Server 2014. There are plenty of people still using SQL Server 2005 but everybody is curious about what is coming in SQL Server 2014.  Microsoft has officially released SQL Server 2014 CTP1 Product Guide. You can easily download the product guide and explore various learning around SQL Server 2014 as well explore the new concepts introduced in this latest version. This SQL Server 2014 CTP1 Product Guide contains few interesting White Papers, a Datasheet and Presentation Deck. Here is the list of the white papers: Mission-Critical Performance and Scale with SQL Server and Windows Server Faster Insights from Any Data Platform for Hybrid Cloud SQL Server In-Memory OLTP Internals Overview for CTP1 SQL Server 2014 CTP1 Frequently Asked Questions for TechEd 2013 North America Here is the list of slide decks: SQL Server 2014 Level 100 Deck SQL Server 2014 Mission Critical Performance LEvel 300 Deck SQL Server 2014 Faster Insights from Any Data Level Level 300 Deck SQL Server 2014 Platform for Hybrid Cloud Level 100 Deck I have earlier downloaded the Product Guide and I have yet not completed reading everything SQL Server 2014 has to offer. If you want to read what are the features which I am going to use in SQL Server 2014, you can read over here. Download Microsoft SQL Server 2014 CTP1 Product Guide Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: PostADay, SQL, SQL Authority, SQL Documentation, SQL Download, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

    Read the article

  • Inserting THEAD element into embedded HTML using jQuery

    - by robalot
    I'm trying to use jQuery to insert HTML into a table element. I've been messing variations of the selector (below) with no luck. Can someone help me? My Selector: $j('#ctl00_body_gridData_dom').children('table:first').append("<thead><tr><td colspan='6'>&nbsp;</td><td align='center' colspan='7'>EM SPECS</td><td align='center' colspan='7'>FISH</td><td colspan='11'>&nbsp;</td></tr></thead>"); Here's what I am trying to do... I want to insert this: <thead> <tr> <td colspan="6"> &nbsp; </td> <td align="center" colspan="7"> EM SPECS </td> <td align="center" colspan="7"> FISH </td> <td colspan="11"> &nbsp; </td> </tr> </thead> The sample below is what I want the end result to look like... So It Looks Like This: Jquery Event Pool <table id="ctl00_body_gridData" style="width: 2000px; -moz-user-select: none;" border="1" cellpadding="0" cellspacing="0"> <tbody> <tr> <td id="ctl00_body_gridData_dom" class="GridData" style="vertical-align: top; height: 245px;" valign="top"> <table style="width: 100%;" border="0" cellpadding="0" cellspacing="0"> <thead> <tr> <td colspan="6"> &nbsp; </td> <td align="center" colspan="7"> EM SPECS </td> <td align="center" colspan="7"> FISH </td> <td colspan="11"> &nbsp; </td> </tr> </thead> <tbody> <tr id="ctl00_body_gridData_top_head" class="headerlineGrid"> <td width="16"> <div style="width: 16px;"></div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,4,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,4,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,0,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,4,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,4,0)" style="width: 89px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 89px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Work<br>Package</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,6,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,6,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,1,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,6,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,6,0)" style="width: 62px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 62px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Work<br>Order</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,9,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,9,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,2,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,9,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,9,0)" style="width: 66px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 66px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> FCR<br>Group</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,12,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,12,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,3,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,12,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,12,0)" style="width: 105px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 105px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center">Contractor</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,15,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,15,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,4,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,15,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,15,0)" style="width: 159px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 159px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Capital/Expense<br>Group</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,19,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,19,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,5,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,19,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,19,0)" style="width: 99px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 99px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center">Cost Type</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,20,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,20,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,6,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,20,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,20,0)" style="width: 81px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 81px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Commit<br>Dollars</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,21,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,21,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,7,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,21,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,21,0)" style="width: 81px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 81px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Commit<br>Hours</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,22,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,22,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,8,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,22,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,22,0)" style="width: 86px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 86px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Commit<br>Quantity</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,23,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,23,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,9,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,23,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,23,0)" style="width: 76px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 76px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Control<br>Budget</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,24,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,24,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,10,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,24,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,24,0)" style="width: 46px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 46px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center">FTC</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,25,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,25,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,11,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,25,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,25,0)" style="width: 88px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 88px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Total<br>Forecast</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,26,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,26,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,12,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,26,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,26,0)" style="width: 50px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 50px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Ctr<br>COB</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,27,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,27,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,13,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,27,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,27,0)" style="width: 49px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 49px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Ctr<br>CCB</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,28,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,28,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,14,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,28,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,28,0)" style="width: 81px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 81px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Ctr<br> Commit<br>$</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,29,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,29,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,15,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,29,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,29,0)" style="width: 81px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 81px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Ctr<br> Commit<br>Hours</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,30,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,30,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,16,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,30,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,30,0)" style="width: 86px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 86px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Ctr<br> Commit<br>Quantity</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,31,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,31,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,17,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,31,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,31,0)" style="width: 95px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 95px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Ctr<br>% Compl.</td> </tr> </tbody> </table> </div> </td> <td onclick="ctl00_body_gridData.ClickHandler(event,this,32,0)" ondblclick="ctl00_body_gridData.DblClickHandler(event,null,32,0)" onmousemove="ctl00_body_gridData.MoveHandler(event,this,18,0)" onmouseover="ctl00_body_gridData.OverHandler(event,this,0)" onmouseout="ctl00_body_gridData.OutHandler(event,this,0)" onmousedown="ctl00_body_gridData.DownHandler(event,this,32,0)" onmouseup="ctl00_body_gridData.UpHandler(event,this,32,0)" style="width: 105px;" class="HeadingCell" align="center"> <div style="text-align: center; overflow: hidden; width: 105px;"> <table width="100%" border="0" cellpadding="0" cellspacing="0"> <tbody> <tr> <td style="white-space: nowrap; text-align: center;" class="HeadingCellText" align="center"> Contractor<br>CFTC</td> </tr> </tbody> </table> </div> </td> </tr> <tr> <td id="ctl00_body_gridData_expcolgrp_0" width="16" align="center"></td> <td class="GroupHeading" colspan="20"> FCR<br>Group: Engineering</td> </tr> <tr> <td id="ctl00_body_gridData_expcolgrp_1" width="16" align="center"></td> <td class="GroupHeading" colspan="20"> FCR<br>Group: Pipe</td> </tr> <tr> <td id="ctl00_body_gridData_expcolgrp_2" width="16" align="center"></td> <td class="GroupHeading" colspan="20"> FCR<br>Group: Concrete</td> </tr> <tr> <td id="ctl00_body_gridData_expcolgrp_3" width="16" align="center"></td> <td class="GroupHeading" colspan="20"> FCR<br>Group: Insulation</td> </tr> <tr> <td id="ctl00_body_gridData_expcolgrp_4" width="16" align="center"></td> <td class="GroupHeading" colspan="20"> FCR<br>Group: Buildings</td> </tr> </tbody> </table> </td> </tr> </tbody> </table> </body> </html>

    Read the article

  • MySQL – Learning MySQL Online in 6 Hours – MySQL Fundamentals in 320 Minutes

    - by Pinal Dave
    MySQL is one of the most popular database language and I have been recently working with it a lot. Data have no barrier and every database have their own place. I have been working with MySQL for quite a while and just like SQL Server, I often find lots of people asking me if I have a tutorial which can teach them MySQL from the beginning. Here is the good news, I have written two different courses on MySQL Fundamentals, which is available online. The reason for writing two different courses was to keep the learning simple. Both of the courses are absolutely connected with other but designed if you watch either of the course independently you can watch them and learn without dependencies. However, if you ask me, I will suggest that you watch MySQL Fundamentals Part 1 course following with MySQL Fundamentals Part 2 course. Let us quickly explore outline of MySQL courses. MySQL Fundamental – 1 (157 minutes) MySQL is a popular choice of database for use in web applications, and is a central component of the widely used LAMP open source web application software stack. This course covers the fundamentals of MySQL, including how to install MySQL as well as written basic data retrieval and data modification queries. Introduction (duration 00:02:12) Installations and GUI Tools (duration 00:13:51) Fundamentals of RDBMS and Database Designs (duration 00:16:13) Introduction MYSQL Workbench (duration 00:31:51) Data Retrieval Techniques (duration 01:11:13) Data Modification Techniques (duration 00:20:41) Summary and Resources (duration 00:01:31) MySQL Fundamental – 2 (163 minutes) MySQL is a popular choice of database for use in web applications, and is a central component of the widely used LAMP open source web application software stack. In this course, which is part 2 of the Fundamentals of MySQL series, we explore more advanced topics such as stored procedures & user-defined functions, subqueries & joins, views and events & triggers. Introduction (duration 00:02:09) Joins, Unions and Subqueries (duration 01:03:56) MySQL Functions (duration 00:36:55) MySQL Views (duration 00:19:19) Stored Procedures and Stored Functions (duration 00:25:23) Triggers and Events (duration 00:13:41) Summary and Resources (duration 00:02:18) Note if you click on the link above and you do not see the play button to watch the course, you will have to login to the system and watch the course. I would like to throw a challenge to you – Can you watch both of the courses in a single day? If yes, once you are done watching the course on your Pluralsight Profile Page (here is my profile http://pluralsight.com/training/users/pinal-dave) you will get following badges. If you have already watched MySQL Fundamental Part 1, you can qualify by just watching MySQL Fundamental Part 2. Just send me the link to your profile and I will publish your name on this blog. For the first five people who send me email at Pinal at sqlauthority.com; I might have something cool as a giveaway as well. Watch the teaser of MySQL course. Reference: Pinal Dave (http://blog.sqlauthority.com)  Filed under: MySQL, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL, Technology

    Read the article

  • SQL Authority News – Presenting at SQL Bangalore on May 3, 2014 – Performing an Effective Presentation

    - by Pinal Dave
    SQL Bangalore is a wonderful community and we always have a great response when we present on technology. It is SQL User Group and we discuss everything SQL there. This month we have SQL Server 2014 theme and we are going to have a community launch on this subject. We have the best of the best speakers presenting on SQL Server 2014 technology. Looking at the whole line of celebrity speakers, I have decided not to present on SQL Server. I will be presenting on the performance tuning subject, but with the twist of soft skills. I will be presenting on “Performing an Effective Presentation“. Trust me, you do not want to miss this presentation, I will be presenting on how to present effectively when presenting SQL Server topics. What this session will NOT have I personally believe that we all are good presenters most of the time. We can all easily call out if someone is bad presenter. There is no point talking about basics like bigger bullet points, talk loudly, talk with confidence, use better analogies etc. In simple words – this is not going to some philosophy session and boring notes. What this session will have Well, this session will tell stories of my life. It will tell how we can present about technology and SQL Server with the help of stories and personal experience. I am going to tell stories about two legends  who have inspired me. Right after that we will be doing two exercises together where we will learn quickly and effectively, how to become better speaker – instantly! There is no video recording of this session. If you want to get resources from this session, please sign up my newsletter at http://bit.ly/sqllearn Here are few of the slides from this presentation: Here is the details about the event and location Venue:Microsoft Corporation, Signature Building,Embassy Golf Links Business Park, Intermediate Ring Road, Domlur, Bangalore – 560071 The agenda is amazing – we have top line SQL Speakers. Everyone is welcome and don’t forget to get your friend along for this event. Loads to learn and tons to share !!! Keynote (20 mins) by Anupam Tiwari – Business Program Manager – GTSC Backup Enhancements with SQL Server 2014 by Amit Banerjee – PFE Microsoft Performance Enhancements with SQL Server 2014 by Sourabh Agarwal - PFE Microsoft LUNCH BREAK Performing an effective Presentation by Pinal Dave – Community Member (SQLAuthority.com) InMemory Enhancements with SQL Server 2014 by Balmukund Lakhani – Support Escalation Engg. Microsoft Some more lesser known enhancements with SQL Server 2014 by Vinod Kumar – Technical Architect Microsoft MTC Power Packed – Power BI with SQL Server by Kane Conway – Support Escalation Engg. Microsoft I am very big fan of Amit, Balmukund and Vinod – I have always watched their session and this time, I am going to once again attend their session without missing a single min. They are SQL legends, I am going to be there and learn when they are sharing their knowledge.  Reference: Pinal Dave (http://blog.sqlauthority.com)Filed under: PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, SQLAuthority Author Visit, T SQL

    Read the article

  • Design by Contract with Microsoft .Net Code Contract

    - by Fredrik N
    I have done some talks on different events and summits about Defensive Programming and Design by Contract, last time was at Cornerstone’s Developer Summit 2010. Next time will be at SweNug (Sweden .Net User Group). I decided to write a blog post about of some stuffs I was talking about. Users are a terrible thing! Protect your self from them ”Human users have a gift for doing the worst possible thing at the worst possible time.” – Michael T. Nygard, Release It! The kind of users Michael T. Nygard are talking about is the users of a system. We also have users that uses our code, the users I’m going to focus on is the users of our code. Me and you and another developers. “Any fool can write code that a computer can understand. Good programmers write code that humans can understand.” – Martin Fowler Good programmers also writes code that humans know how to use, good programmers also make sure software behave in a predictable manner despise inputs or user actions. Design by Contract   Design by Contract (DbC) is a way for us to make a contract between us (the code writer) and the users of our code. It’s about “If you give me this, I promise to give you this”. It’s not about business validations, that is something completely different that should be part of the domain model. DbC is to make sure the users of our code uses it in a correct way, and that we can rely on the contract and write code in a way where we know that the users will follow the contract. It will make it much easier for us to write code with a contract specified. Something like the following code is something we may see often: public void DoSomething(Object value) { value.DoIKnowThatICanDoThis(); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Where “value” can be uses directly or passed to other methods and later be used. What some of us can easily forget here is that the “value” can be “null”. We will probably not passing a null value, but someone else that uses our code maybe will do it. I think most of you (including me) have passed “null” into a method because you don’t know if the argument need to be specified to a valid value etc. I bet most of you also have got the “Null reference exception”. Sometimes this “Null reference exception” can be hard and take time to fix, because we need to search among our code to see where the “null” value was passed in etc. Wouldn’t it be much better if we can as early as possible specify that the value can’t not be null, so the users of our code also know it when the users starts to use our code, and before run time execution of the code? This is where DbC comes into the picture. We can use DbC to specify what we need, and by doing so we can rely on the contract when we write our code. So the code above can actually use the DoIKnowThatICanDoThis() method on the value object without being worried that the “value” can be null. The contract between the users of the code and us writing the code, says that the “value” can’t be null.   Pre- and Postconditions   When working with DbC we are specifying pre- and postconditions.  Precondition is a condition that should be met before a query or command is executed. An example of a precondition is: “The Value argument of the method can’t be null”, and we make sure the “value” isn’t null before the method is called. Postcondition is a condition that should be met when a command or query is completed, a postcondition will make sure the result is correct. An example of a postconditon is “The method will return a list with at least 1 item”. Commands an Quires When using DbC, we need to know what a Command and a Query is, because some principles that can be good to follow are based on commands and queries. A Command is something that will not return anything, like the SQL’s CREATE, UPDATE and DELETE. There are two kinds of Commands when using DbC, the Creation commands (for example a Constructor), and Others. Others can for example be a Command to add a value to a list, remove or update a value etc. //Creation commands public Stack(int size) //Other commands public void Push(object value); public void Remove(); .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   A Query, is something that will return something, for example an Attribute, Property or a Function, like the SQL’s SELECT.   There are two kinds of Queries, the Basic Queries  (Quires that aren’t based on another queries), and the Derived Queries, queries that is based on another queries. Here is an example of queries of a Stack: //Basic Queries public int Count; public object this[int index] { get; } //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } To understand about some principles that are good to follow when using DbC, we need to know about the Commands and different Queries. The 6 Principles When working with DbC, it’s advisable to follow some principles to make it easier to define and use contracts. The following DbC principles are: Separate commands and queries. Separate basic queries from derived queries. For each derived query, write a postcondition that specifies what result will be returned, in terms of one or more basic queries. For each command, write a postcondition that specifies the value of every basic query. For every query and command, decide on a suitable precondition. Write invariants to define unchanging properties of objects. Before I will write about each of them I want you to now that I’m going to use .Net 4.0 Code Contract. I will in the rest of the post uses a simple Stack (Yes I know, .Net already have a Stack class) to give you the basic understanding about using DbC. A Stack is a data structure where the first item in, will be the first item out. Here is a basic implementation of a Stack where not contract is specified yet: public class Stack { private object[] _array; //Basic Queries public uint Count; public object this[uint index] { get { return _array[index]; } set { _array[index] = value; } } //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } //Is related to Count and this[] Query public object Top() { return this[Count]; } //Creation commands public Stack(uint size) { Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { this[++Count] = value; } public void Remove() { this[Count] = null; Count--; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: The Stack is implemented in a way to demonstrate the use of Code Contract in a simple way, the implementation may not look like how you would implement it, so don’t think this is the perfect Stack implementation, only used for demonstration.   Before I will go deeper into the principles I will simply mention how we can use the .Net Code Contract. I mention before about pre- and postcondition, is about “Require” something and to “Ensure” something. When using Code Contract, we will use a static class called “Contract” and is located in he “System.Diagnostics.Contracts” namespace. The contract must be specified at the top or our member statement block. To specify a precondition with Code Contract we uses the Contract.Requires method, and to specify a postcondition, we uses the Contract.Ensure method. Here is an example where both a pre- and postcondition are used: public object Top() { Contract.Requires(Count > 0, "Stack is empty"); Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The contract above requires that the Count is greater than 0, if not we can’t get the item at the Top of a Stack. We also Ensures that the results (By using the Contract.Result method, we can specify a postcondition that will check if the value returned from a method is correct) of the Top query is equal to this[Count].   1. Separate Commands and Queries   When working with DbC, it’s important to separate Command and Quires. A method should either be a command that performs an Action, or returning information to the caller, not both. By asking a question the answer shouldn’t be changed. The following is an example of a Command and a Query of a Stack: public void Push(object value) public object Top() .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   The Push is a command and will not return anything, just add a value to the Stack, the Top is a query to get the item at the top of the stack.   2. Separate basic queries from derived queries There are two different kinds of queries,  the basic queries that doesn’t rely on another queries, and derived queries that uses a basic query. The “Separate basic queries from derived queries” principle is about about that derived queries can be specified in terms of basic queries. So this principles is more about recognizing that a query is a derived query or a basic query. It will then make is much easier to follow the other principles. The following code shows a basic query and a derived query: //Basic Queries public uint Count; //Derived Queries //Is related to Count Query public bool IsEmpty() { return Count == 0; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   We can see that IsEmpty will use the Count query, and that makes the IsEmpty a Derived query.   3. For each derived query, write a postcondition that specifies what result will be returned, in terms of one or more basic queries.   When the derived query is recognize we can follow the 3ed principle. For each derived query, we can create a postcondition that specifies what result our derived query will return in terms of one or more basic queries. Remember that DbC is about contracts between the users of the code and us writing the code. So we can’t use demand that the users will pass in a valid value, we must also ensure that we will give the users what the users wants, when the user is following our contract. The IsEmpty query of the Stack will use a Count query and that will make the IsEmpty a Derived query, so we should now write a postcondition that specified what results will be returned, in terms of using a basic query and in this case the Count query, //Basic Queries public uint Count; //Derived Queries public bool IsEmpty() { Contract.Ensures(Contract.Result<bool>() == (Count == 0)); return Count == 0; } The Contract.Ensures is used to create a postcondition. The above code will make sure that the results of the IsEmpty (by using the Contract.Result to get the result of the IsEmpty method) is correct, that will say that the IsEmpty will be either true or false based on Count is equal to 0 or not. The postcondition are using a basic query, so the IsEmpty is now following the 3ed principle. We also have another Derived Query, the Top query, it will also need a postcondition and it uses all basic queries. The Result of the Top method must be the same value as the this[] query returns. //Basic Queries public uint Count; public object this[uint index] { get { return _array[index]; } set { _array[index] = value; } } //Derived Queries //Is related to Count and this[] Query public object Top() { Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   4. For each command, write a postcondition that specifies the value of every basic query.   For each command we will create a postconditon that specifies the value of basic queries. If we look at the Stack implementation we will have three Commands, one Creation command, the Constructor, and two others commands, Push and Remove. Those commands need a postcondition and they should include basic query to follow the 4th principle. //Creation commands public Stack(uint size) { Contract.Ensures(Count == 0); Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { Contract.Ensures(Count == Contract.OldValue<uint>(Count) + 1); Contract.Ensures(this[Count] == value); this[++Count] = value; } public void Remove() { Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   As you can see the Create command will Ensures that Count will be 0 when the Stack is created, when a Stack is created there shouldn’t be any items in the stack. The Push command will take a value and put it into the Stack, when an item is pushed into the Stack, the Count need to be increased to know the number of items added to the Stack, and we must also make sure the item is really added to the Stack. The postconditon of the Push method will make sure the that old value of the Count (by using the Contract.OldValue we can get the value a Query has before the method is called)  plus 1 will be equal to the Count query, this is the way we can ensure that the Push will increase the Count with one. We also make sure the this[] query will now contain the item we pushed into the Stack. The Remove method must make sure the Count is decreased by one when the top item is removed from the Stack. The Commands is now following the 4th principle, where each command now have a postcondition that used the value of basic queries. Note: The principle says every basic Query, the Remove only used one Query the Count, it’s because this command can’t use the this[] query because an item is removed, so the only way to make sure an item is removed is to just use the Count query, so the Remove will still follow the principle.   5. For every query and command, decide on a suitable precondition.   We have now focused only on postcondition, now time for some preconditons. The 5th principle is about deciding a suitable preconditon for every query and command. If we starts to look at one of our basic queries (will not go through all Queries and commands here, just some of them) the this[] query, we can’t pass an index that is lower then 1 (.Net arrays and list are zero based, but not the stack in this blog post ;)) and the index can’t be lesser than the number of items in the stack. So here we will need a preconditon. public object this[uint index] { get { Contract.Requires(index >= 1); Contract.Requires(index <= Count); return _array[index]; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Think about the Contract as an documentation about how to use the code in a correct way, so if the contract could be specified elsewhere (not part of the method body), we could simply write “return _array[index]” and there is no need to check if index is greater or lesser than Count, because that is specified in a “contract”. The implementation of Code Contract, requires that the contract is specified in the code. As a developer I would rather have this contract elsewhere (Like Spec#) or implemented in a way Eiffel uses it as part of the language. Now when we have looked at one Query, we can also look at one command, the Remove command (You can see the whole implementation of the Stack at the end of this blog post, where precondition is added to more queries and commands then what I’m going to show in this section). We can only Remove an item if the Count is greater than 0. So we can write a precondition that will require that Count must be greater than 0. public void Remove() { Contract.Requires(Count > 0); Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   6. Write invariants to define unchanging properties of objects.   The last principle is about making sure the object are feeling great! This is done by using invariants. When using Code Contract we can specify invariants by adding a method with the attribute ContractInvariantMethod, the method must be private or public and can only contains calls to Contract.Invariant. To make sure the Stack feels great, the Stack must have 0 or more items, the Count can’t never be a negative value to make sure each command and queries can be used of the Stack. Here is our invariant for the Stack object: [ContractInvariantMethod] private void ObjectInvariant() { Contract.Invariant(Count >= 0); } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; }   Note: The ObjectInvariant method will be called every time after a Query or Commands is called. Here is the full example using Code Contract:   public class Stack { private object[] _array; //Basic Queries public uint Count; public object this[uint index] { get { Contract.Requires(index >= 1); Contract.Requires(index <= Count); return _array[index]; } set { Contract.Requires(index >= 1); Contract.Requires(index <= Count); _array[index] = value; } } //Derived Queries //Is related to Count Query public bool IsEmpty() { Contract.Ensures(Contract.Result<bool>() == (Count == 0)); return Count == 0; } //Is related to Count and this[] Query public object Top() { Contract.Requires(Count > 0, "Stack is empty"); Contract.Ensures(Contract.Result<object>() == this[Count]); return this[Count]; } //Creation commands public Stack(uint size) { Contract.Requires(size > 0); Contract.Ensures(Count == 0); Count = 0; _array = new object[size]; } //Other commands public void Push(object value) { Contract.Requires(value != null); Contract.Ensures(Count == Contract.OldValue<uint>(Count) + 1); Contract.Ensures(this[Count] == value); this[++Count] = value; } public void Remove() { Contract.Requires(Count > 0); Contract.Ensures(Count == Contract.OldValue<uint>(Count) - 1); this[Count] = null; Count--; } [ContractInvariantMethod] private void ObjectInvariant() { Contract.Invariant(Count >= 0); } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Summary By using Design By Contract we can make sure the users are using our code in a correct way, and we must also make sure the users will get the expected results when they uses our code. This can be done by specifying contracts. To make it easy to use Design By Contract, some principles may be good to follow like the separation of commands an queries. With .Net 4.0 we can use the Code Contract feature to specify contracts.

    Read the article

  • Add logo background color to data returned by StackAuth sites route

    - by Yi Jiang
    Given that now with Stack Exchange 2.0 the logo of some of the sites, like Web Apps, AskUbuntu, Photography, Gaming and Pro Webmasters have non-white background, I think it will be best if the StackAuth sites route can include the preferred background color for those the logo of these sites. This is especially important for sites like Photography whose logo is unreadable if the traditional white is used. Edit: Here's an example of what I mean here: As you can see, the AskUbuntu logo text totally invisible against a white background.

    Read the article

facebook twitter digg google delicious technorati stumbleupon myspace wordpress linkedin gmail igoogle windows live tumblr viadeo yahoo buzz yahoo mail yahoo bookmarks favorites email print

< Previous Page | 23 24 25 26 27 28 29 30 31 32 33 34  | Next Page >