Search Results

Search found 269 results on 11 pages for 'sealed'.

Page 9/11 | < Previous Page | 5 6 7 8 9 10 11  | Next Page >

  • C# language questions

    - by Water Cooler v2
    1) What is int? Is it any different from the struct System.Int32? I understand that the former is a C# alias (typedef or #define equivalant) for the CLR type System.Int32. Is this understanding correct? 2) When we say: IComparable x = 10; Is that like saying: IComparable x = new System.Int32(); But we can't new a struct, right? or in C like syntax: struct System.In32 *x; x=>someThing = 10; 3) What is String with a capitalized S? I see in Reflector that it is the sealed String class, which, of course, is a reference type, unlike the System.Int32 above, which is a value type. What is string, with an uncapitalized s, though? Is that also the C# alias for this class? Why can I not see the alias definitions in Reflector? 4) Try to follow me down this subtle train of thought, if you please. We know that a storage location of a particular type can only access properties and members on its interface. That means: Person p = new Customer(); p.Name = "Water Cooler v2"; // legal because as Name is defined on Person. but // illegal without an explicit cast even though the backing // store is a Customer, the storage location is of type // Person, which doesn't support the member/method being // accessed/called. p.GetTotalValueOfOrdersMade(); Now, with that inference, consider this scenario: int i = 10; // obvious System.object defines no member to // store an integer value or any other value in. // So, my question really is, when the integer is // boxed, what is the *type* it is actually boxed to. // In other words, what is the type that forms the // backing store on the heap, for this operation? object x = i;

    Read the article

  • Ninject: Singleton binding syntax?

    - by Rosarch
    I'm using Ninject 2.0 for the .Net 3.5 framework. I'm having difficulty with singleton binding. I have a class UserInputReader which implements IInputReader. I only want one instance of this class to ever be created. public class MasterEngineModule : NinjectModule { public override void Load() { // using this line and not the other two makes it work //Bind<IInputReader>().ToMethod(context => new UserInputReader(Constants.DEFAULT_KEY_MAPPING)); Bind<IInputReader>().To<UserInputReader>(); Bind<UserInputReader>().ToSelf().InSingletonScope(); } } static void Main(string[] args) { IKernel ninject = new StandardKernel(new MasterEngineModule()); MasterEngine game = ninject.Get<MasterEngine>(); game.Run(); } public sealed class UserInputReader : IInputReader { public static readonly IInputReader Instance = new UserInputReader(Constants.DEFAULT_KEY_MAPPING); // ... public UserInputReader(IDictionary<ActionInputType, Keys> keyMapping) { this.keyMapping = keyMapping; } } If I make that constructor private, it breaks. What am I doing wrong here?

    Read the article

  • Our VPS is being used as a Warez mule

    - by Mikuso
    The company I work for runs a series of ecommerce stores on a VPS. It's a WAMP stack, 50gb storage. We use an archaic piece of ecommerce software which operates almost entirely client-side. When an order is taken, it writes it to disk and then we schedule a task to download the orders once every 10 minutes. A few days ago, we ran out of disk space, which caused orders to fail to be written. I quickly hopped on to delete some old logs from the mailserver and freed up a couple of GB pretty quickly, but I wondered how we could fill up 50gb will nothing much more than logs. Turns out, we didn't. Hidden deep within the c:\System Volume Information directory, we have a stack of pirated videos, which seem to have appeared (looking at the timestamps) over the past three weeks. Porn, American Sports, Australian cooking shows. A very odd collection. Doesn't look like an individual's personal tastes - more like the VPS is being used as a mule. We have a 5-attempts and you're blocked policy on our FTP server (plus, there is no FTP account with access to that directory), and the windows user account has had it's password changed recently. The main avenues are sealed - and logs can verify that. I thought I'd watch and see if it happened again, and yes, another cooking show has appeared this morning. I am the only one to know of this problem at my company, and only one of two with access to the VPS (the other being my boss, but no - it's not him). So how is this happening? Is there a vulnerability in some of the software on the VPS? Are the VPS owners peddling warez across our rented space? (can they do this?) I don't want to delete the warez in case it is seen as a hostile action against this outside force, and they choose to retaliate. What should I do? How do I troubleshoot this? Has this happened to anyone else before?

    Read the article

  • What are incentives (if any) to use WinRT instead of .Net?

    - by Ark-kun
    Let's compare WinRT with .Net .Net .Net is the 13+ years evolution of COM. Three main parts of .Net are execution environment, standard libraries and supported languages. CLR is the native-code execution environment based on COM .Net Framework has a big set of standard libraries (implemented using managed and native code) that can be used from all .Net languages. There are .Net classes that allow using OS APIs. WPF or Silverlight provide a XAML-based UI framework .Net can be used with C++, C#, Javascript, Python, Ruby, VB, LISP, Scheme and many other languages. C++/.Net is a variation of the C++ language that allows interaction with .Net objects. .Net supports inheritance, generics, operator and method overloading and many other features. .Net allows creating apps that run on Windows (XP, 7, 8 Pro (Desktop and Metro), RT, CE, etc), Mac OS, Linux (+ other *nix); iOS, Android, Windows Phone (7, 8); Internet Explorer, Chrome, Firefox; XBox 360, Playstation Suite; raw microprocessors. There is support for creating games (2D/3D) using any managed language or C++. Created by Developer Division WinRT WinRT is based on COM. Three main parts of WinRT are execution environment, standard libraries and supported languages. WinRT has a native-code execution environment based on COM WinRT has a set of standard libraries that more or less can be used from WinRT languages. There are WinRT classes that allow using OS APIs. Unnamed Silverlight clone provides a XAML-based UI framework WinRT can be used with C++, C#, Javascript, VB. C++/CX is a variation of the C++ language that allows interaction with WinRT objects. Custom WinRT components don't support inheritance (classes must be sealed), generics, operator overloading and many other features. WinRT allows creating apps that run on Windows 8 Pro and RT (Metro only); Windows Phone 8 (limited). There is support for creating games (2D/3D) using C++ only. Ordered by Windows Team I think that all the aspects except the last ones are very important for developers. On the other hand it seems that the most important aspect for Microsoft is the last one. So, given the above comparison of conceptually identical technologies, what are incentives (if any) to use WinRT instead of .Net?

    Read the article

  • Why won't my Windows 8 Command line update its path

    - by mawcsco
    I needed to add a new entry to my PATH variable. This is a common activity for me in my job, but I've recently started using Windows 8. I assumed the process would be similar to Windows 7, Vista, XP... Here's my sequence of events: Open System properties (Start- [type "Control Panel"] - Control Panel\System and Security\System - Advanced system settings - Environment Variables) Add the new path to beginning of my USER PATH variable (C:\dev\Java\apache-ant-1.8.4\bin;) Opened a command prompt (Start - [type "command prompt" enter] - [type "path" enter] My new path entry is not available (see attached image and vide). I Duplicated the exact same process on a Windows 7 machine and it worked. EDIT Windows 8 Environment Variables and Command Prompt video EDIT This is definitely not the behavior of Windows 7. Watch this video to see the behavior I expect working in Windows 7. http://youtu.be/95JXY5X0fII EDIT 5/31/2013 So, after much frustration, I wrote a small C# app to test the WM_SETTINGCHANGE event. This code receives the event in both Windows 7 and Windows 8. However, in Windows 8 on my system, I do not get the correct path; but, I do in Windows 7. This could not be reproduced in other Windows 8 systems. Here is the C# code. using System; using Microsoft.Win32; public sealed class App { static void Main() { SystemEvents.UserPreferenceChanging += new UserPreferenceChangingEventHandler(OnUserPreferenceChanging); Console.WriteLine("Waiting for system events."); Console.WriteLine("Press <Enter> to exit."); Console.ReadLine(); } static void OnUserPreferenceChanging(object sender, UserPreferenceChangingEventArgs e) { Console.WriteLine("The user preference is changing. Category={0}", e.Category); Console.WriteLine("path={0}", System.Environment.GetEnvironmentVariable("PATH")); } } OnUserPreferenceChanging is equivalent to WM_SETTINGCHANGE C# program running in Windows 7 (you can see the event come through and it picks up the correct path). C# program running in Windows 8 (you can see the event come through, but the wrong path). There is something about my environment that is precipitating this problem. However, is this a Windows 8 bug?

    Read the article

  • SharePoint 2010 – Central Admin tooling to create host header site collections

    - by eJugnoo
    Just like SharePoint 2007, you can create host-header based site collections in SharePoint 2010 as well. It means, that you do not necessarily need to create a site-collection under a managed path like /sites/, you can create multiple root-level site collections on same web-application/port by using host-header site collections. All you need to do is point your domain or sub-domain to your web-application and create a matching site-collection that you want. But, just like in 2007, it is something that you do by using STSADM, and is not available on Central Admin UI in 2010 as well. Yeah, though you can now also use PowerShell to create one: C:\PS>$w = Get-SPWebApplication http://sitename   C:\PS>New-SPSite http://www.contoso.com -OwnerAlias "DOMAIN\jdoe" -HostHeaderWebApplication $w -Title "Contoso" -Template "STS#0"   This example creates a host header site collection. Because the template is provided, the root Web of this site collection will be created. .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’ve been playing with WCM in SharePoint 2010 more and more, and for that I preferred creating hosts file entries for desired domains and create site-collections by those headers – in my dev environment. I used PowerShell initially, but then got interested to build my own UI on Central Admin instead. Developed with Visual Studio 2010 So I used new Visual Studio 2010 tooling to create an empty SharePoint 2010 project. Added an application page (there is no option to add _Admin page item in VS 2010 RC), that got created in Layouts “mapped” folder. Created a new Admin mapped folder for 14-“hive”, and moved my new page there instead. Yes, I didn’t change the base class for page, its just that it runs under _admin, but it is indeed a LayoutsPageBase inherited page. To introduce a action-link in Central Admin console, I created following element: 1: <Elements xmlns="http://schemas.microsoft.com/sharepoint/"> 2: <CustomAction 3: Id="CreateSiteByHeader" 4: Location="Microsoft.SharePoint.Administration.Applications" 5: Title="Create site collections by host header" 6: GroupId="SiteCollections" 7: Sequence="15" 8: RequiredAdmin="Delegated" 9: Description="Create a new top-level web site, by host header" > 10: <UrlAction Url="/_admin/OfficeToolbox/CreateSiteByHeader.aspx" /> 11: </CustomAction> 12: </Elements> .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; } Used Reflector to understand any special code behind createpage.aspx, and created a new for our purpose – CreateSiteByHeader.aspx. From there I quickly created a similar code behind, without all the fancy of Farm Config Wizard handling and dealt with alternate implementations of sealed classes! Goal was to create a professional looking and OOB-type experience. I also added Regex validation to ensure user types a valid domain name as header value. Below is the result…   Release @ Codeplex I’ve released to WSP on OfficeToolbox @ Codeplex, and you can download from here. Hope you find it useful… -- Sharad

    Read the article

  • Guarding against CSRF Attacks in ASP.NET MVC2

    - by srkirkland
    Alongside XSS (Cross Site Scripting) and SQL Injection, Cross-site Request Forgery (CSRF) attacks represent the three most common and dangerous vulnerabilities to common web applications today. CSRF attacks are probably the least well known but they are relatively easy to exploit and extremely and increasingly dangerous. For more information on CSRF attacks, see these posts by Phil Haack and Steve Sanderson. The recognized solution for preventing CSRF attacks is to put a user-specific token as a hidden field inside your forms, then check that the right value was submitted. It's best to use a random value which you’ve stored in the visitor’s Session collection or into a Cookie (so an attacker can't guess the value). ASP.NET MVC to the rescue ASP.NET MVC provides an HTMLHelper called AntiForgeryToken(). When you call <%= Html.AntiForgeryToken() %> in a form on your page you will get a hidden input and a Cookie with a random string assigned. Next, on your target Action you need to include [ValidateAntiForgeryToken], which handles the verification that the correct token was supplied. Good, but we can do better Using the AntiForgeryToken is actually quite an elegant solution, but adding [ValidateAntiForgeryToken] on all of your POST methods is not very DRY, and worse can be easily forgotten. Let's see if we can make this easier on the program but moving from an "Opt-In" model of protection to an "Opt-Out" model. Using AntiForgeryToken by default In order to mandate the use of the AntiForgeryToken, we're going to create an ActionFilterAttribute which will do the anti-forgery validation on every POST request. First, we need to create a way to Opt-Out of this behavior, so let's create a quick action filter called BypassAntiForgeryToken: [AttributeUsage(AttributeTargets.Method, AllowMultiple=false)] public class BypassAntiForgeryTokenAttribute : ActionFilterAttribute { } Now we are ready to implement the main action filter which will force anti forgery validation on all post actions within any class it is defined on: [AttributeUsage(AttributeTargets.Class, AllowMultiple = false)] public class UseAntiForgeryTokenOnPostByDefault : ActionFilterAttribute { public override void OnActionExecuting(ActionExecutingContext filterContext) { if (ShouldValidateAntiForgeryTokenManually(filterContext)) { var authorizationContext = new AuthorizationContext(filterContext.Controller.ControllerContext);   //Use the authorization of the anti forgery token, //which can't be inhereted from because it is sealed new ValidateAntiForgeryTokenAttribute().OnAuthorization(authorizationContext); }   base.OnActionExecuting(filterContext); }   /// <summary> /// We should validate the anti forgery token manually if the following criteria are met: /// 1. The http method must be POST /// 2. There is not an existing [ValidateAntiForgeryToken] attribute on the action /// 3. There is no [BypassAntiForgeryToken] attribute on the action /// </summary> private static bool ShouldValidateAntiForgeryTokenManually(ActionExecutingContext filterContext) { var httpMethod = filterContext.HttpContext.Request.HttpMethod;   //1. The http method must be POST if (httpMethod != "POST") return false;   // 2. There is not an existing anti forgery token attribute on the action var antiForgeryAttributes = filterContext.ActionDescriptor.GetCustomAttributes(typeof(ValidateAntiForgeryTokenAttribute), false);   if (antiForgeryAttributes.Length > 0) return false;   // 3. There is no [BypassAntiForgeryToken] attribute on the action var ignoreAntiForgeryAttributes = filterContext.ActionDescriptor.GetCustomAttributes(typeof(BypassAntiForgeryTokenAttribute), false);   if (ignoreAntiForgeryAttributes.Length > 0) return false;   return true; } } The code above is pretty straight forward -- first we check to make sure this is a POST request, then we make sure there aren't any overriding *AntiForgeryTokenAttributes on the action being executed. If we have a candidate then we call the ValidateAntiForgeryTokenAttribute class directly and execute OnAuthorization() on the current authorization context. Now on our base controller, you could use this new attribute to start protecting your site from CSRF vulnerabilities. [UseAntiForgeryTokenOnPostByDefault] public class ApplicationController : System.Web.Mvc.Controller { }   //Then for all of your controllers public class HomeController : ApplicationController {} What we accomplished If your base controller has the new default anti-forgery token attribute on it, when you don't use <%= Html.AntiForgeryToken() %> in a form (or of course when an attacker doesn't supply one), the POST action will throw the descriptive error message "A required anti-forgery token was not supplied or was invalid". Attack foiled! In summary, I think having an anti-CSRF policy by default is an effective way to protect your websites, and it turns out it is pretty easy to accomplish as well. Enjoy!

    Read the article

  • Getting a Web Resource Url in non WebForms Applications

    - by Rick Strahl
    WebResources in ASP.NET are pretty useful feature. WebResources are resources that are embedded into a .NET assembly and can be loaded from the assembly via a special resource URL. WebForms includes a method on the ClientScriptManager (Page.ClientScript) and the ScriptManager object to retrieve URLs to these resources. For example you can do: ClientScript.GetWebResourceUrl(typeof(ControlResources), ControlResources.JQUERY_SCRIPT_RESOURCE); GetWebResourceUrl requires a type (which is used for the assembly lookup in which to find the resource) and the resource id to lookup. GetWebResourceUrl() then returns a nasty old long URL like this: WebResource.axd?d=-b6oWzgbpGb8uTaHDrCMv59VSmGhilZP5_T_B8anpGx7X-PmW_1eu1KoHDvox-XHqA1EEb-Tl2YAP3bBeebGN65tv-7-yAimtG4ZnoWH633pExpJor8Qp1aKbk-KQWSoNfRC7rQJHXVP4tC0reYzVw2&t=634533278261362212 While lately excessive resource usage has been frowned upon especially by MVC developers who tend to opt for content distributed as files, I still think that Web Resources have their place even in non-WebForms applications. Also if you have existing assemblies that include resources like scripts and common image links it sure would be nice to access them from non-WebForms pages like MVC views or even in plain old Razor Web Pages. Where's my Page object Dude? Unfortunately natively ASP.NET doesn't have a mechanism for retrieving WebResource Urls outside of the WebForms engine. It's a feature that's specifically baked into WebForms and that relies specifically on the Page HttpHandler implementation. Both Page.ClientScript (obviously) and ScriptManager rely on a hosting Page object in order to work and the various methods off these objects require control instances passed. The reason for this is that the script managers can inject scripts and links into Page content (think RegisterXXXX methods) and for that a Page instance is required. However, for many other methods - like GetWebResourceUrl() - that simply return resources or resource links the Page reference is really irrelevant. While there's a separate ClientScriptManager class, it's marked as sealed and doesn't have any public constructors so you can't create your own instance (without Reflection). Even if it did the internal constructor it does have requires a Page reference. No good… So, can we get access to a WebResourceUrl generically without running in a WebForms Page instance? We just have to create a Page instance ourselves and use it internally. There's nothing intrinsic about the use of the Page class in ClientScript, at least for retrieving resources and resource Urls so it's easy to create an instance of a Page for example in a static method. For our needs of retrieving ResourceUrls or even actually retrieving script resources we can use a canned, non-configured Page instance we create on our own. The following works just fine: public static string GetWebResourceUrl(Type type, string resource ) { Page page = new Page(); return page.ClientScript.GetWebResourceUrl(type, resource); } A slight optimization for this might be to cache the created Page instance. Page tends to be a pretty heavy object to create each time a URL is required so you might want to cache the instance: public class WebUtils { private static Page CachedPage { get { if (_CachedPage == null) _CachedPage = new Page(); return _CachedPage; } } private static Page _CachedPage; public static string GetWebResourceUrl(Type type, string resource) { return CachedPage.ClientScript.GetWebResourceUrl(type, resource); } } You can now use GetWebResourceUrl in a Razor page like this: <!DOCTYPE html> <html <head> <script src="@WebUtils.GetWebResourceUrl(typeof(ControlResources),ControlResources.JQUERY_SCRIPT_RESOURCE)"> </script> </head> <body> <div class="errordisplay"> <img src="@WebUtils.GetWebResourceUrl(typeof(ControlResources),ControlResources.WARNING_ICON_RESOURCE)" /> This is only a Test! </div> </body> </html> And voila - there you have WebResources served from a non-Page based application. WebResources may be a on the way out, but legacy apps have them embedded and for some situations, like fallback scripts and some common image resources I still like to use them. Being able to use them from non-WebForms applications should have been built into the core ASP.NETplatform IMHO, but seeing that it's not this workaround is easy enough to implement.© Rick Strahl, West Wind Technologies, 2005-2011Posted in ASP.NET  MVC   Tweet (function() { var po = document.createElement('script'); po.type = 'text/javascript'; po.async = true; po.src = 'https://apis.google.com/js/plusone.js'; var s = document.getElementsByTagName('script')[0]; s.parentNode.insertBefore(po, s); })();

    Read the article

  • Persisting settings without using Options dialog in Visual Studio

    - by Utkarsh Shigihalli
    Originally posted on: http://geekswithblogs.net/onlyutkarsh/archive/2013/11/02/persisting-settings-without-using-options-dialog-in-visual-studio.aspxIn one of my previous blog post we have seen persisting settings using Visual Studio's options dialog. Visual Studio options has many advantages in automatically persisting user options for you. However, during our latest Team Rooms extension development, we decided to provide our users; ability to use our preferences directly from Team Explorer. The main reason was that we had only one simple option for user and we thought it is cumbersome for user to go to Tools –> Options dialog to change this. Another reason was, we wanted to highlight this setting to user as soon as he is using our extension.   So if you are in such a scenario where you do not want to use VS options window, but still would like to persist the settings, this post will guide you through. Visual Studio SDK provides two ways to persist settings in your extensions. One is using DialogPage as shown in my previous post. Another way is to use by implementing IProfileManager interface which I will explain in this post. Please note that the class implementing IProfileManager should be independent class. This is because, VS instantiates this class during Tools –> Import and Export Settings. IProfileManager provides 2 different sets of methods (total 4 methods) to persist the settings. They are LoadSettingsFromXml and SaveSettingsToXml – Implement these methods to persist settings to disk from VS settings storage. The VS will persist your settings along with other options to disk. LoadSettingsFromStorage and SaveSettingsToStorage – Implement these methods to persist settings to local storage, usually it be registry. VS calls LoadSettingsFromStorage method when it is initializing the package too. We are going to use the 2nd set of methods for this example. First, we are creating a separate class file called UserOptions.cs. Please note that, we also need to implement IComponent, which can be done by inheriting Component along with IProfileManager. [ComVisible(true)] [Guid("XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXXXXXX")] public class UserOptions : Component, IProfileManager { private const string SUBKEY_NAME = "TForVS2013"; private const string TRAY_NOTIFICATIONS_STRING = "TrayNotifications"; ... } Define the property so that it can be used to set and get from other classes. public bool TrayNotifications { get; set; } Implement the members of IProfileManager. public void LoadSettingsFromStorage() { RegistryKey reg = null; try { using (reg = Package.UserRegistryRoot.OpenSubKey(SUBKEY_NAME)) { if (reg != null) { // Key already exists, so just update this setting. TrayNotifications = Convert.ToBoolean(reg.GetValue(TRAY_NOTIFICATIONS_STRING, true)); } } } catch (TeamRoomException exception) { TrayNotifications = true; ExceptionReporting.Report(exception); } finally { if (reg != null) { reg.Close(); } } } public void LoadSettingsFromXml(IVsSettingsReader reader) { reader.ReadSettingBoolean(TRAY_NOTIFICATIONS_STRING, out _isTrayNotificationsEnabled); TrayNotifications = (_isTrayNotificationsEnabled == 1); } public void ResetSettings() { } public void SaveSettingsToStorage() { RegistryKey reg = null; try { using (reg = Package.UserRegistryRoot.OpenSubKey(SUBKEY_NAME, true)) { if (reg != null) { // Key already exists, so just update this setting. reg.SetValue(TRAY_NOTIFICATIONS_STRING, TrayNotifications); } else { reg = Package.UserRegistryRoot.CreateSubKey(SUBKEY_NAME); reg.SetValue(TRAY_NOTIFICATIONS_STRING, TrayNotifications); } } } catch (TeamRoomException exception) { ExceptionReporting.Report(exception); } finally { if (reg != null) { reg.Close(); } } } public void SaveSettingsToXml(IVsSettingsWriter writer) { writer.WriteSettingBoolean(TRAY_NOTIFICATIONS_STRING, TrayNotifications ? 1 : 0); } Let me elaborate on the method implementation. The Package class provides UserRegistryRoot (which is HKCU\Microsoft\VisualStudio\12.0 for VS2013) property which can be used to create and read the registry keys. So basically, in the methods above, I am checking if the registry key exists already and if not, I simply create it. Also, in case there is an exception I return the default values. If the key already exists, I update the value. Also, note that you need to make sure that you close the key while exiting from the method. Very simple right? Accessing and settings is simple too. We just need to use the exposed property. UserOptions.TrayNotifications = true; UserOptions.SaveSettingsToStorage(); Reading settings is as simple as reading a property. UserOptions.LoadSettingsFromStorage(); var trayNotifications = UserOptions.TrayNotifications; Lastly, the most important step. We need to tell Visual Studio shell that our package exposes options using the UserOptions class. For this we need to decorate our package class with ProvideProfile attribute as below. [ProvideProfile(typeof(UserOptions), "TForVS2013", "TeamRooms", 110, 110, false, DescriptionResourceID = 401)] public sealed class TeamRooms : Microsoft.VisualStudio.Shell.Package { ... } That's it. If everything is alright, once you run the package you will also see your options appearing in "Import Export settings" window, which allows you to export your options.

    Read the article

  • .NET 4: &ldquo;Slim&rdquo;-style performance boost!

    - by Vitus
    RTM version of .NET 4 and Visual Studio 2010 is available, and now we can do some test with it. Parallel Extensions is one of the most valuable part of .NET 4.0. It’s a set of good tools for easily consuming multicore hardware power. And it also contains some “upgraded” sync primitives – Slim-version. For example, it include updated variant of widely known ManualResetEvent. For people, who don’t know about it: you can sync concurrency execution of some pieces of code with this sync primitive. Instance of ManualResetEvent can be in 2 states: signaled and non-signaled. Transition between it possible by Set() and Reset() methods call. Some shortly explanation: Thread 1 Thread 2 Time mre.Reset(); mre.WaitOne(); //code execution 0 //wating //code execution 1 //wating //code execution 2 //wating //code execution 3 //wating mre.Set(); 4 //code execution //… 5 Upgraded version of this primitive is ManualResetEventSlim. The idea in decreasing performance cost in case, when only 1 thread use it. Main concept in the “hybrid sync schema”, which can be done as following:   internal sealed class SimpleHybridLock : IDisposable { private Int32 m_waiters = 0; private AutoResetEvent m_waiterLock = new AutoResetEvent(false);   public void Enter() { if (Interlocked.Increment(ref m_waiters) == 1) return; m_waiterLock.WaitOne(); }   public void Leave() { if (Interlocked.Decrement(ref m_waiters) == 0) return; m_waiterLock.Set(); }   public void Dispose() { m_waiterLock.Dispose(); } } It’s a sample from Jeffry Richter’s book “CLR via C#”, 3rd edition. Primitive SimpleHybridLock have two public methods: Enter() and Leave(). You can put your concurrency-critical code between calls of these methods, and it would executed in only one thread at the moment. Code is really simple: first thread, called Enter(), increase counter. Second thread also increase counter, and suspend while m_waiterLock is not signaled. So, if we don’t have concurrent access to our lock, “heavy” methods WaitOne() and Set() will not called. It’s can give some performance bonus. ManualResetEvent use the similar idea. Of course, it have more “smart” technics inside, like a checking of recursive calls, and so on. I want to know a real difference between classic ManualResetEvent realization, and new –Slim. I wrote a simple “benchmark”: class Program { static void Main(string[] args) { ManualResetEventSlim mres = new ManualResetEventSlim(false); ManualResetEventSlim mres2 = new ManualResetEventSlim(false);   ManualResetEvent mre = new ManualResetEvent(false);   long total = 0; int COUNT = 50;   for (int i = 0; i < COUNT; i++) { mres2.Reset(); Stopwatch sw = Stopwatch.StartNew();   ThreadPool.QueueUserWorkItem((obj) => { //Method(mres, true); Method2(mre, true); mres2.Set(); }); //Method(mres, false); Method2(mre, false);   mres2.Wait(); sw.Stop();   Console.WriteLine("Pass {0}: {1} ms", i, sw.ElapsedMilliseconds); total += sw.ElapsedMilliseconds; }   Console.WriteLine(); Console.WriteLine("==============================="); Console.WriteLine("Done in average=" + total / (double)COUNT); Console.ReadLine(); }   private static void Method(ManualResetEventSlim mre, bool value) { for (int i = 0; i < 9000000; i++) { if (value) { mre.Set(); } else { mre.Reset(); } } }   private static void Method2(ManualResetEvent mre, bool value) { for (int i = 0; i < 9000000; i++) { if (value) { mre.Set(); } else { mre.Reset(); } } } } I use 2 concurrent thread (the main thread and one from thread pool) for setting and resetting ManualResetEvents, and try to run test COUNT times, and calculate average execution time. Here is the results (I get it on my dual core notebook with T7250 CPU and Windows 7 x64): ManualResetEvent ManualResetEventSlim Difference is obvious and serious – in 10 times! So, I think preferable way is using ManualResetEventSlim, because not always on calling Set() and Reset() will be called “heavy” methods for working with Windows kernel-mode objects. It’s a small and nice improvement! ;)

    Read the article

  • Upgrading SSIS Custom Components for SQL Server 2012

    Having finally got around to upgrading my custom components to SQL Server 2012, I thought I’d share some notes on the process. One of the goals was minimal duplication, so the same code files are used to build the 2008 and 2012 components, I just have a separate project file. The high level steps are listed below, followed by some more details. Create a 2012 copy of the project file Upgrade project, just open the new project file is VS2010 Change target framework to .NET 4.0 Set conditional compilation symbol for DENALI Change any conditional code, including assembly version and UI type name Edit project file to change referenced assemblies for 2012 Change target framework to .NET 4.0 Open the project properties. On the Applications page, change the Target framework to .NET Framework 4. Set conditional compilation symbol for DENALI Re-open the project properties. On the Build tab, first change the Configuration to All Configurations, then set a Conditional compilation symbol of DENALI. Change any conditional code, including assembly version and UI type name The value doesn’t have to be DENALI, it can actually be anything you like, that is just what I use. It is how I control sections of code that vary between versions. There were several API changes between 2005 and 2008, as well as interface name changes. Whilst we don’t have the same issues between 2008 and 2012, I still have some sections of code that do change such as the assembly attributes. #if DENALI [assembly: AssemblyDescription("Data Generator Source for SQL Server Integration Services 2012")] [assembly: AssemblyCopyright("Copyright © 2012 Konesans Ltd")] [assembly: AssemblyVersion("3.0.0.0")] #else [assembly: AssemblyDescription("Data Generator Source for SQL Server Integration Services 2008")] [assembly: AssemblyCopyright("Copyright © 2008 Konesans Ltd")] [assembly: AssemblyVersion("2.0.0.0")] #endif The Visual Studio editor automatically formats the code based on the current compilation symbols, hence in this case the 2008 code is grey to indicate it is disabled. As you can see in the previous example I have distinct assembly version attributes, ensuring I can run both 2008 and 2012 versions of my component side by side. For custom components with a user interface, be sure to update the UITypeName property of the DtsTask or DtsPipelineComponent attributes. As above I use the conditional compilation symbol to control the code. #if DENALI [DtsTask ( DisplayName = "File Watcher Task", Description = "File Watcher Task", IconResource = "Konesans.Dts.Tasks.FileWatcherTask.FileWatcherTask.ico", UITypeName = "Konesans.Dts.Tasks.FileWatcherTask.FileWatcherTaskUI,Konesans.Dts.Tasks.FileWatcherTask,Version=3.0.0.0,Culture=Neutral,PublicKeyToken=b2ab4a111192992b", TaskContact = "File Watcher Task; Konesans Ltd; Copyright © 2012 Konesans Ltd; http://www.konesans.com" )] #else [DtsTask ( DisplayName = "File Watcher Task", Description = "File Watcher Task", IconResource = "Konesans.Dts.Tasks.FileWatcherTask.FileWatcherTask.ico", UITypeName = "Konesans.Dts.Tasks.FileWatcherTask.FileWatcherTaskUI,Konesans.Dts.Tasks.FileWatcherTask,Version=2.0.0.0,Culture=Neutral,PublicKeyToken=b2ab4a111192992b", TaskContact = "File Watcher Task; Konesans Ltd; Copyright © 2004-2008 Konesans Ltd; http://www.konesans.com" )] #endif public sealed class FileWatcherTask: Task, IDTSComponentPersist, IDTSBreakpointSite, IDTSSuspend { // .. code goes on... } Shown below is another example I found that needed changing. I borrow one of the MS editors, and use it against a custom property, but need to ensure I reference the correct version of the MS controls assembly. This section of code is actually shared between the 2005, 2008 and 2012 versions of my component hence it has test for both DENALI and KATMAI symbols. #if DENALI const string multiLineUI = "Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version=11.0.00.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91"; #elif KATMAI const string multiLineUI = "Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91"; #else const string multiLineUI = "Microsoft.DataTransformationServices.Controls.ModalMultilineStringEditor, Microsoft.DataTransformationServices.Controls, Version=9.0.242.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91"; #endif // Create Match Expression parameter IDTSCustomPropertyCollection100 propertyCollection = outputColumn.CustomPropertyCollection; IDTSCustomProperty100 property = propertyCollection.New(); property = propertyCollection.New(); property.Name = MatchParams.Name; property.Description = MatchParams.Description; property.TypeConverter = typeof(MultilineStringConverter).AssemblyQualifiedName; property.UITypeEditor = multiLineUI; property.Value = MatchParams.DefaultValue; Edit project file to change referenced assemblies for 2012 We now need to edit the project file itself. Open the MyComponente2012.cproj  in you favourite text editor, and then perform a couple of find and replaces as listed below: Find Replace Comment Version=10.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91 Version=11.0.0.0, Culture=neutral, PublicKeyToken=89845dcd8080cc91 Change the assembly references version from SQL Server 2008 to SQL Server 2012. Microsoft SQL Server\100\ Microsoft SQL Server\110\ Change any assembly reference hint path locations from from SQL Server 2008 to SQL Server 2012. If you use any Build Events during development, such as copying the component assembly to the DTS folder, or calling GACUTIL to install it into the GAC, you can also change these now. An example of my new post-build event for a pipeline component is shown below, which uses the .NET 4.0 path for GACUTIL. It also uses the 110 folder location, instead of 100 for SQL Server 2008, but that was covered the the previous find and replace. "C:\Program Files (x86)\Microsoft SDKs\Windows\v7.0A\Bin\NETFX 4.0 Tools\gacutil.exe" /if "$(TargetPath)" copy "$(TargetPath)" "%ProgramFiles%\Microsoft SQL Server\110\DTS\PipelineComponents" /Y

    Read the article

  • Why enumerator structs are a really bad idea

    - by Simon Cooper
    If you've ever poked around the .NET class libraries in Reflector, I'm sure you would have noticed that the generic collection classes all have implementations of their IEnumerator as a struct rather than a class. As you will see, this design decision has some rather unfortunate side effects... As is generally known in the .NET world, mutable structs are a Very Bad Idea; and there are several other blogs around explaining this (Eric Lippert's blog post explains the problem quite well). In the BCL, the generic collection enumerators are all mutable structs, as they need to keep track of where they are in the collection. This bit me quite hard when I was coding a wrapper around a LinkedList<int>.Enumerator. It boils down to this code: sealed class EnumeratorWrapper : IEnumerator<int> { private readonly LinkedList<int>.Enumerator m_Enumerator; public EnumeratorWrapper(LinkedList<int> linkedList) { m_Enumerator = linkedList.GetEnumerator(); } public int Current { get { return m_Enumerator.Current; } } object System.Collections.IEnumerator.Current { get { return Current; } } public bool MoveNext() { return m_Enumerator.MoveNext(); } public void Reset() { ((System.Collections.IEnumerator)m_Enumerator).Reset(); } public void Dispose() { m_Enumerator.Dispose(); } } The key line here is the MoveNext method. When I initially coded this, I thought that the call to m_Enumerator.MoveNext() would alter the enumerator state in the m_Enumerator class variable and so the enumeration would proceed in an orderly fashion through the collection. However, when I ran this code it went into an infinite loop - the m_Enumerator.MoveNext() call wasn't actually changing the state in the m_Enumerator variable at all, and my code was looping forever on the first collection element. It was only after disassembling that method that I found out what was going on The MoveNext method above results in the following IL: .method public hidebysig newslot virtual final instance bool MoveNext() cil managed { .maxstack 1 .locals init ( [0] bool CS$1$0000, [1] valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator CS$0$0001) L_0000: nop L_0001: ldarg.0 L_0002: ldfld valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator EnumeratorWrapper::m_Enumerator L_0007: stloc.1 L_0008: ldloca.s CS$0$0001 L_000a: call instance bool [System]System.Collections.Generic.LinkedList`1/Enumerator::MoveNext() L_000f: stloc.0 L_0010: br.s L_0012 L_0012: ldloc.0 L_0013: ret } Here, the important line is 0002 - m_Enumerator is accessed using the ldfld operator, which does the following: Finds the value of a field in the object whose reference is currently on the evaluation stack. So, what the MoveNext method is doing is the following: public bool MoveNext() { LinkedList<int>.Enumerator CS$0$0001 = this.m_Enumerator; bool CS$1$0000 = CS$0$0001.MoveNext(); return CS$1$0000; } The enumerator instance being modified by the call to MoveNext is the one stored in the CS$0$0001 variable on the stack, and not the one in the EnumeratorWrapper class instance. Hence why the state of m_Enumerator wasn't getting updated. Hmm, ok. Well, why is it doing this? If you have a read of Eric Lippert's blog post about this issue, you'll notice he quotes a few sections of the C# spec. In particular, 7.5.4: ...if the field is readonly and the reference occurs outside an instance constructor of the class in which the field is declared, then the result is a value, namely the value of the field I in the object referenced by E. And my m_Enumerator field is readonly! Indeed, if I remove the readonly from the class variable then the problem goes away, and the code works as expected. The IL confirms this: .method public hidebysig newslot virtual final instance bool MoveNext() cil managed { .maxstack 1 .locals init ( [0] bool CS$1$0000) L_0000: nop L_0001: ldarg.0 L_0002: ldflda valuetype [System]System.Collections.Generic.LinkedList`1/Enumerator EnumeratorWrapper::m_Enumerator L_0007: call instance bool [System]System.Collections.Generic.LinkedList`1/Enumerator::MoveNext() L_000c: stloc.0 L_000d: br.s L_000f L_000f: ldloc.0 L_0010: ret } Notice on line 0002, instead of the ldfld we had before, we've got a ldflda, which does this: Finds the address of a field in the object whose reference is currently on the evaluation stack. Instead of loading the value, we're loading the address of the m_Enumerator field. So now the call to MoveNext modifies the enumerator stored in the class rather than on the stack, and everything works as expected. Previously, I had thought enumerator structs were an odd but interesting feature of the BCL that I had used in the past to do linked list slices. However, effects like this only underline how dangerous mutable structs are, and I'm at a loss to explain why the enumerators were implemented as structs in the first place. (interestingly, the SortedList<TKey, TValue> enumerator is a struct but is private, which makes it even more odd - the only way it can be accessed is as a boxed IEnumerator!). I would love to hear people's theories as to why the enumerators are implemented in such a fashion. And bonus points if you can explain why LinkedList<int>.Enumerator.Reset is an explicit implementation but Dispose is implicit... Note to self: never ever ever code a mutable struct.

    Read the article

  • Configuring Application/User Settings in WPF the easy way.

    - by mbcrump
    In this tutorial, we are going to configure the application/user settings in a WPF application the easy way. Most example that I’ve seen on the net involve the ConfigurationManager class and involve creating your own XML file from scratch. I am going to show you a easier way to do it. (in my humble opinion) First, the definitions: User Setting – is designed to be something specific to the user. For example, one user may have a requirement to see certain stocks, news articles or local weather. This can be set at run-time. Application Setting – is designed to store information such as a database connection string. These settings are read-only at run-time. 1) Lets create a new WPF Project and play with a few settings. Once you are inside VS, then paste the following code snippet inside the <Grid> tags. <Grid> <TextBox Height="23" HorizontalAlignment="Left" Margin="12,11,0,0" Name="textBox1" VerticalAlignment="Top" Width="285" Grid.ColumnSpan="2" /> <Button Content="Set Title" Name="button2" Click="button2_Click" Margin="108,40,96,114" /> <TextBlock Height="23" Name="textBlock1" Text="TextBlock" VerticalAlignment="Bottom" Width="377" /> </Grid> Basically, its just a Textbox, Button and TextBlock. The main Window should look like the following:   2) Now we are going to setup our Configuration Settings. Look in the Solution Explorer and double click on the Settings.settings file. Make sure that your settings file looks just like mine included below:   What just happened was the designer created an XML file and created the Settings.Designer.cs file which looks like this: //------------------------------------------------------------------------------ // <auto-generated> // This code was generated by a tool. // Runtime Version:4.0.30319.1 // // Changes to this file may cause incorrect behavior and will be lost if // the code is regenerated. // </auto-generated> //------------------------------------------------------------------------------ namespace WPFExam.Properties { [global::System.Runtime.CompilerServices.CompilerGeneratedAttribute()] [global::System.CodeDom.Compiler.GeneratedCodeAttribute("Microsoft.VisualStudio.Editors.SettingsDesigner.SettingsSingleFileGenerator", "10.0.0.0")] internal sealed partial class Settings : global::System.Configuration.ApplicationSettingsBase { private static Settings defaultInstance = ((Settings)(global::System.Configuration.ApplicationSettingsBase.Synchronized(new Settings()))); public static Settings Default { get { return defaultInstance; } } [global::System.Configuration.UserScopedSettingAttribute()] [global::System.Diagnostics.DebuggerNonUserCodeAttribute()] [global::System.Configuration.DefaultSettingValueAttribute("ApplicationName")] public string ApplicationName { get { return ((string)(this["ApplicationName"])); } set { this["ApplicationName"] = value; } } [global::System.Configuration.ApplicationScopedSettingAttribute()] [global::System.Diagnostics.DebuggerNonUserCodeAttribute()] [global::System.Configuration.DefaultSettingValueAttribute("SQL_SRV342")] public string DatabaseServerName { get { return ((string)(this["DatabaseServerName"])); } } } } The XML File is named app.config and looks like this: <?xml version="1.0" encoding="utf-8" ?> <configuration> <configSections> <sectionGroup name="userSettings" type="System.Configuration.UserSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" > <section name="WPFExam.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" allowExeDefinition="MachineToLocalUser" requirePermission="false" /> </sectionGroup> <sectionGroup name="applicationSettings" type="System.Configuration.ApplicationSettingsGroup, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" > <section name="WPFExam.Properties.Settings" type="System.Configuration.ClientSettingsSection, System, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" /> </sectionGroup> </configSections> <userSettings> <WPFExam.Properties.Settings> <setting name="ApplicationName" serializeAs="String"> <value>ApplicationName</value> </setting> </WPFExam.Properties.Settings> </userSettings> <applicationSettings> <WPFExam.Properties.Settings> <setting name="DatabaseServerName" serializeAs="String"> <value>SQL_SRV342</value> </setting> </WPFExam.Properties.Settings> </applicationSettings> </configuration> 3) The only left now is the code behind the button. Double click the button and replace the MainWindow() method with the following code snippet. public MainWindow() { InitializeComponent(); this.Title = Properties.Settings.Default.ApplicationName; textBox1.Text = Properties.Settings.Default.ApplicationName; textBlock1.Text = Properties.Settings.Default.DatabaseServerName; } private void button2_Click(object sender, RoutedEventArgs e) { Properties.Settings.Default.ApplicationName = textBox1.Text.ToString(); Properties.Settings.Default.Save(); } Run the application and type something in the textbox and hit the Set Title button. Now, restart the application and you should see the text that you entered earlier.   If you look at the button2 click event, you will see that it was actually 2 lines of codes to save to the configuration file. I hope this helps, for more information consult MSDN.

    Read the article

  • Team Foundation Server (TFS) Team Build Custom Activity C# Code for Assembly Stamping

    - by Bob Hardister
    For the full context and guidance on how to develop and implement a custom activity in Team Build see the Microsoft Visual Studio Rangers Team Foundation Build Customization Guide V.1 at http://vsarbuildguide.codeplex.com/ There are many ways to stamp or set the version number of your assemblies. This approach is based on the build number.   namespace CustomActivities { using System; using System.Activities; using System.IO; using System.Text.RegularExpressions; using Microsoft.TeamFoundation.Build.Client; [BuildActivity(HostEnvironmentOption.Agent)] public sealed class VersionAssemblies : CodeActivity { /// <summary> /// AssemblyInfoFileMask /// </summary> [RequiredArgument] public InArgument<string> AssemblyInfoFileMask { get; set; } /// <summary> /// SourcesDirectory /// </summary> [RequiredArgument] public InArgument<string> SourcesDirectory { get; set; } /// <summary> /// BuildNumber /// </summary> [RequiredArgument] public InArgument<string> BuildNumber { get; set; } /// <summary> /// BuildDirectory /// </summary> [RequiredArgument] public InArgument<string> BuildDirectory { get; set; } /// <summary> /// Publishes field values to the build report /// </summary> public OutArgument<string> DiagnosticTextOut { get; set; } // If your activity returns a value, derive from CodeActivity<TResult> and return the value from the Execute method. protected override void Execute(CodeActivityContext context) { // Obtain the runtime value of the input arguments string sourcesDirectory = context.GetValue(this.SourcesDirectory); string assemblyInfoFileMask = context.GetValue(this.AssemblyInfoFileMask); string buildNumber = context.GetValue(this.BuildNumber); string buildDirectory = context.GetValue(this.BuildDirectory); // ** Determine the version number values ** // Note: the format used here is: major.secondary.maintenance.build // ----------------------------------------------------------------- // Obtain the build definition name int nameStart = buildDirectory.LastIndexOf(@"\") + 1; string buildDefinitionName = buildDirectory.Substring(nameStart); // Set the primary.secondary.maintenance values // NOTE: these are hard coded in this example, but could be sourced from a file or parsed from a build definition name that includes them string p = "1"; string s = "5"; string m = "2"; // Initialize the build number string b; string na = "0"; // used for Assembly and Product Version instead of build number (see versioning best practices: **TBD reference) // Set qualifying product version information string productInfo = "RC2"; // Obtain the build increment number from the build number // NOTE: this code assumes the default build definition name format int buildIncrementNumberDelimterIndex = buildNumber.LastIndexOf("."); b = buildNumber.Substring(buildIncrementNumberDelimterIndex + 1); // Convert version to integer values int pVer = Convert.ToInt16(p); int sVer = Convert.ToInt16(s); int mVer = Convert.ToInt16(m); int bNum = Convert.ToInt16(b); int naNum = Convert.ToInt16(na); // ** Get all AssemblyInfo files and stamp them ** // Note: the mapping of AssemblyInfo.cs attributes to assembly display properties are as follows: // - AssemblyVersion = Assembly Version - used for the assembly version (does not change unless p, s or m values are changed) // - AssemblyFileVersion = File Version - used for the file version (changes with every build) // - AssemblyInformationalVersion = Product Version - used for the product version (can include additional version information) // ------------------------------------------------------------------------------------------------------------------------------------------------ Version assemblyVersion = new Version(pVer, sVer, mVer, naNum); Version newAssemblyFileVersion = new Version(pVer, sVer, mVer, bNum); Version productVersion = new Version(pVer, sVer, mVer); // Setup diagnostic fields int numberOfReplacements = 0; string addedAssemblyInformationalAttribute = "No"; // Enumerate over the assemblyInfo version attributes foreach (string attribute in new[] { "AssemblyVersion", "AssemblyFileVersion", "AssemblyInformationalVersion" }) { // Define the regular expression to find in each and every Assemblyinfo.cs files (which is for example 'AssemblyVersion("1.0.0.0")' ) Regex regex = new Regex(attribute + @"\(""\d+\.\d+\.\d+\.\d+""\)"); foreach (string file in Directory.EnumerateFiles(sourcesDirectory, assemblyInfoFileMask, SearchOption.AllDirectories)) { string text = File.ReadAllText(file); // Read the text from the AssemblyInfo file // If the AsemblyInformationalVersion attribute is not in the file, add it as the last line of the file // Note: by default the AssemblyInfo.cs files will not contain the AssemblyInformationalVersion attribute if (!text.Contains("[assembly: AssemblyInformationalVersion(\"")) { string lastLine = Environment.NewLine + "[assembly: AssemblyInformationalVersion(\"1.0.0.0\")]"; text = text + lastLine; addedAssemblyInformationalAttribute = "Yes"; } // Search for the expression Match match = regex.Match(text); if (match.Success) { // Get file attributes FileAttributes fileAttributes = File.GetAttributes(file); // Set file to read only File.SetAttributes(file, fileAttributes & ~FileAttributes.ReadOnly); // Insert AssemblyInformationalVersion attribute into the file text if does not already exist string newText = string.Empty; if (attribute == "AssemblyVersion") { newText = regex.Replace(text, attribute + "(\"" + assemblyVersion + "\")"); numberOfReplacements++; } if (attribute == "AssemblyFileVersion") { newText = regex.Replace(text, attribute + "(\"" + newAssemblyFileVersion + "\")"); numberOfReplacements++; } if (attribute == "AssemblyInformationalVersion") { newText = regex.Replace(text, attribute + "(\"" + productVersion + " " + productInfo + "\")"); numberOfReplacements++; } // Publish diagnostics to build report (diagnostic verbosity only) context.SetValue(this.DiagnosticTextOut, " Added AssemblyInformational Attribute: " + addedAssemblyInformationalAttribute + " Number of replacements: " + numberOfReplacements + " Build number: " + buildNumber + " Build directory: " + buildDirectory + " Build definition name: " + buildDefinitionName + " Assembly version: " + assemblyVersion + " New file version: " + newAssemblyFileVersion + " Product version: " + productVersion + " AssemblyInfo.cs Text Last Stamped: " + newText); // Write the new text in the AssemblyInfo file File.WriteAllText(file, newText); // restore the file's original attributes File.SetAttributes(file, fileAttributes); } } } } } }

    Read the article

  • yield – Just yet another sexy c# keyword?

    - by George Mamaladze
    yield (see NSDN c# reference) operator came I guess with .NET 2.0 and I my feeling is that it’s not as wide used as it could (or should) be.   I am not going to talk here about necessarity and advantages of using iterator pattern when accessing custom sequences (just google it).   Let’s look at it from the clean code point of view. Let's see if it really helps us to keep our code understandable, reusable and testable.   Let’s say we want to iterate a tree and do something with it’s nodes, for instance calculate a sum of their values. So the most elegant way would be to build a recursive method performing a classic depth traversal returning the sum.           private int CalculateTreeSum(Node top)         {             int sumOfChildNodes = 0;             foreach (Node childNode in top.ChildNodes)             {                 sumOfChildNodes += CalculateTreeSum(childNode);             }             return top.Value + sumOfChildNodes;         }     “Do One Thing” Nevertheless it violates one of the most important rules “Do One Thing”. Our  method CalculateTreeSum does two things at the same time. It travels inside the tree and performs some computation – in this case calculates sum. Doing two things in one method is definitely a bad thing because of several reasons: ·          Understandability: Readability / refactoring ·          Reuseability: when overriding - no chance to override computation without copying iteration code and vice versa. ·          Testability: you are not able to test computation without constructing the tree and you are not able to test correctness of tree iteration.   I want to spend some more words on this last issue. How do you test the method CalculateTreeSum when it contains two in one: computation & iteration? The only chance is to construct a test tree and assert the result of the method call, in our case the sum against our expectation. And if the test fails you do not know wether was the computation algorithm wrong or was that the iteration? At the end to top it all off I tell you: according to Murphy’s Law the iteration will have a bug as well as the calculation. Both bugs in a combination will cause the sum to be accidentally exactly the same you expect and the test will PASS. J   Ok let’s use yield! That’s why it is generally a very good idea not to mix but isolate “things”. Ok let’s use yield!           private int CalculateTreeSumClean(Node top)         {             IEnumerable<Node> treeNodes = GetTreeNodes(top);             return CalculateSum(treeNodes);         }             private int CalculateSum(IEnumerable<Node> nodes)         {             int sumOfNodes = 0;             foreach (Node node in nodes)             {                 sumOfNodes += node.Value;             }             return sumOfNodes;         }           private IEnumerable<Node> GetTreeNodes(Node top)         {             yield return top;             foreach (Node childNode in top.ChildNodes)             {                 foreach (Node currentNode in GetTreeNodes(childNode))                 {                     yield return currentNode;                 }             }         }   Two methods does not know anything about each other. One contains calculation logic another jut the iteration logic. You can relpace the tree iteration algorithm from depth traversal to breath trevaersal or use stack or visitor pattern instead of recursion. This will not influence your calculation logic. And vice versa you can relace the sum with product or do whatever you want with node values, the calculateion algorithm is not aware of beeng working on some tree or graph.  How about not using yield? Now let’s ask the question – what if we do not have yield operator? The brief look at the generated code gives us an answer. The compiler generates a 150 lines long class to implement the iteration logic.       [CompilerGenerated]     private sealed class <GetTreeNodes>d__0 : IEnumerable<Node>, IEnumerable, IEnumerator<Node>, IEnumerator, IDisposable     {         ...        150 Lines of generated code        ...     }   Often we compromise code readability, cleanness, testability, etc. – to reduce number of classes, code lines, keystrokes and mouse clicks. This is the human nature - we are lazy. Knowing and using such a sexy construct like yield, allows us to be lazy, write very few lines of code and at the same time stay clean and do one thing in a method. That's why I generally welcome using staff like that.   Note: The above used recursive depth traversal algorithm is possibly the compact one but not the best one from the performance and memory utilization point of view. It was taken to emphasize on other primary aspects of this post.

    Read the article

  • Asp.net MVC2 Custom jquery validation: client -side

    - by Lullaby
    Hi. I want to create a validation rule for 2 date-pickers (startDate less then endDate). I create a validation attribute: [AttributeUsage(AttributeTargets.Class, AllowMultiple = true, Inherited = true)] public sealed class DateCompareAttribute : ValidationAttribute { private const string _defaultErrorMessage = "'{0}' is less then '{1}'."; public DateCompareAttribute(string startDateProperty, string endDateProperty) : base(_defaultErrorMessage) { StartDateProperty = startDateProperty; EndDateProperty = endDateProperty; } public string StartDateProperty { get; private set; } public string EndDateProperty { get; private set; } public override string FormatErrorMessage(string name) { return String.Format(CultureInfo.CurrentUICulture, ErrorMessageString, StartDateProperty, EndDateProperty); } public override bool IsValid(object value) { PropertyDescriptorCollection properties = TypeDescriptor.GetProperties(value); object startValue = properties.Find(StartDateProperty, true).GetValue(value); object endValue = properties.Find(EndDateProperty, true).GetValue(value); if (startValue.GetType() == typeof(DateTime?) && endValue.GetType() == typeof(DateTime?)) { var start = ((DateTime?)startValue); var end = ((DateTime?)endValue); return (start.Value < end.Value); } return false; } } and added ti to my Dto: [DateCompare("StartDate", "EndDate")] public class QualificationInput{...} I created a validator: public class DateCompareValidator : DataAnnotationsModelValidator { string startField; private string endField; string _message; public DateCompareValidator(ModelMetadata metadata, ControllerContext context , DateCompareAttribute attribute) : base(metadata, context, attribute) { startField = attribute.StartDateProperty; endField = attribute.EndDateProperty; _message = attribute.ErrorMessage; } public override IEnumerable<ModelClientValidationRule> GetClientValidationRules() { var rule = new ModelClientValidationRule { ErrorMessage = _message, ValidationType = "dateCompare" }; rule.ValidationParameters.Add("startField", startField); rule.ValidationParameters.Add("endField", endField); return new[] { rule }; } } And registered it in Global.asax.cs in Application_Start(): DataAnnotationsModelValidatorProvider .RegisterAdapter(typeof(DateCompareAttribute), typeof(DateCompareValidator)); In MicrosoftMvcJQueryValidation.js I have made this changes: switch (thisRule.ValidationType) { ..... case "dateCompare": __MVC_ApplyValidator_DateCompare(rulesObj, thisRule.ValidationParameters["startField"], thisRule.ValidationParameters["endField"]); break; ..... } .... function __MVC_ApplyValidator_DateCompare(object, startField, endField) { object["startField"] = startField; object["endField"] = endField; } jQuery.validator.addMethod("dateCompare", function(value, element, params) { if ($('#' + params["startField"]).val() < $('#' + params["endField"]).val()) { return true; } return false; }, jQuery.format("Error")); But it doesn't work :( no client side validation on this type of rule (the others type like required works fine) What I'm doing wrong?

    Read the article

  • C# 4.0 'dynamic' and foreach statement

    - by ControlFlow
    Not long time before I've discovered, that new dynamic keyword doesn't work well with the C#'s foreach statement: using System; sealed class Foo { public struct FooEnumerator { int value; public bool MoveNext() { return true; } public int Current { get { return value++; } } } public FooEnumerator GetEnumerator() { return new FooEnumerator(); } static void Main() { foreach (int x in new Foo()) { Console.WriteLine(x); if (x >= 100) break; } foreach (int x in (dynamic)new Foo()) { // :) Console.WriteLine(x); if (x >= 100) break; } } } I've expected that iterating over the dynamic variable should work completely as if the type of collection variable is known at compile time. I've discovered that the second loop actually is looked like this when is compiled: foreach (object x in (IEnumerable) /* dynamic cast */ (object) new Foo()) { ... } and every access to the x variable results with the dynamic lookup/cast so C# ignores that I've specify the correct x's type in the foreach statement - that was a bit surprising for me... And also, C# compiler completely ignores that collection from dynamically typed variable may implements IEnumerable<T> interface! The full foreach statement behavior is described in the C# 4.0 specification 8.8.4 The foreach statement article. But... It's perfectly possible to implement the same behavior at runtime! It's possible to add an extra CSharpBinderFlags.ForEachCast flag, correct the emmited code to looks like: foreach (int x in (IEnumerable<int>) /* dynamic cast with the CSharpBinderFlags.ForEachCast flag */ (object) new Foo()) { ... } And add some extra logic to CSharpConvertBinder: Wrap IEnumerable collections and IEnumerator's to IEnumerable<T>/IEnumerator<T>. Wrap collections doesn't implementing Ienumerable<T>/IEnumerator<T> to implement this interfaces. So today foreach statement iterates over dynamic completely different from iterating over statically known collection variable and completely ignores the type information, specified by user. All that results with the different iteration behavior (IEnumarble<T>-implementing collections is being iterated as only IEnumerable-implementing) and more than 150x slowdown when iterating over dynamic. Simple fix will results a much better performance: foreach (int x in (IEnumerable<int>) dynamicVariable) { But why I should write code like this? It's very nicely to see that sometimes C# 4.0 dynamic works completely the same if the type will be known at compile-time, but it's very sadly to see that dynamic works completely different where IT CAN works the same as statically typed code. So my question is: why foreach over dynamic works different from foreach over anything else?

    Read the article

  • Custom validator not invoked when using Validation Application Block through configuration

    - by Chris
    I have set up a ruleset in my configuration file which has two validators, one of which is a built-in NotNullValidator, the other of which is a custom validator. The problem is that I see the NotNullValidator hit, but not my custom validator. The custom validator is being used to validate an Entity Framework entity object. I have used the debugger to confirm the NotNull is hit (I forced a failure condition so I saw it set an invalid result), but it never steps into the custom one. I am using MVC as the web app, so I defined the ruleset in a config file at that layer, but my custom validator is defined in another project. However, I wouldn't have thought that to be a problem because when I use the Enterprise Library Configuration tool inside Visual Studio 2008 it is able to set the type properly for the custom validator. As well, I believe the custom validator is fine as it builds ok, and the config tool can reference it properly. Does anybody have any ideas what the problem could be, or even what to do/try to debug further? Here is a stripped down version of my custom validator: [ConfigurationElementType(typeof(CustomValidatorData))] public sealed class UserAccountValidator : Validator { public UserAccountValidator(NameValueCollection attributes) : base(string.Empty, "User Account") { } protected override string DefaultMessageTemplate { get { throw new NotImplementedException(); } } protected override void DoValidate(object objectToValidate, object currentTarget, string key, ValidationResults results) { if (!currentTarget.GetType().Equals(typeof(UserAccount))) { throw new Exception(); } UserAccount userAccountToValidate = (UserAccount)currentTarget; // snipped code ... this.LogValidationResult(results, "The User Account is invalid", currentTarget, key); } } Here is the XML of my ruleset in Validation.config (the NotNull rule is only there to force a failure so I could see it getting hit, and it does): <validation> <type defaultRuleset="default" assemblyName="MyProj.Entities, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" name="MyProj.Entities.UserAccount"> <ruleset name="default"> <properties> <property name="HashedPassword"> <validator negated="true" messageTemplate="" messageTemplateResourceName="" messageTemplateResourceType="" tag="" type="Microsoft.Practices.EnterpriseLibrary.Validation.Validators.NotNullValidator, Microsoft.Practices.EnterpriseLibrary.Validation, Version=4.1.0.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" name="Not Null Validator" /> </property> <property name="Property"> <validator messageTemplate="" messageTemplateResourceName="" messageTemplateResourceType="" tag="" type="MyProj.Entities.UserAccountValidator, MyProj.Entities, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" name="Custom Validator" /> </property> </properties> </ruleset> </type> </validation> And here is the stripped down version of the way I invoke the validation: var type = entity.GetType() var validator = ValidationFactory.CreateValidator(type, "default", new FileConfigurationSource("Validation.config")) var results = validator.Validate(entity) Any advice would be much appreciated! Thanks, Chris

    Read the article

  • Get aspect ratio of a monitor

    - by Alexander Stalt
    I want to get aspect ratio of a monitor as two digits : width and height. For example 4 and 3, 5 and 4, 16 and 9. I wrote some code for that task. Maybe it is any easier way to do that ? For example, some library function =\ /// <summary> /// Aspect ratio. /// </summary> public struct AspectRatio { int _height; /// <summary> /// Height. /// </summary> public int Height { get { return _height; } } int _width; /// <summary> /// Width. /// </summary> public int Width { get { return _width; } } /// <summary> /// Ctor. /// </summary> /// <param name="height">Height of aspect ratio.</param> /// <param name="width">Width of aspect ratio.</param> public AspectRatio(int height, int width) { _height = height; _width = width; } } public sealed class Aux { /// <summary> /// Get aspect ratio. /// </summary> /// <returns>Aspect ratio.</returns> public static AspectRatio GetAspectRatio() { int deskHeight = Screen.PrimaryScreen.Bounds.Height; int deskWidth = Screen.PrimaryScreen.Bounds.Width; int gcd = GCD(deskWidth, deskHeight); return new AspectRatio(deskHeight / gcd, deskWidth / gcd); } /// <summary> /// Greatest Common Denominator (GCD). Euclidean algorithm. /// </summary> /// <param name="a">Width.</param> /// <param name="b">Height.</param> /// <returns>GCD.</returns> static int GCD(int a, int b) { return b == 0 ? a : GCD(b, a % b); } }

    Read the article

  • Common DataAnnotations in ASP.Net MVC2

    - by Scott Mayfield
    Howdy, I have what should be a simple question. I have a set of validations that use System.CompontentModel.DataAnnotations . I have some validations that are specific to certain view models, so I'm comfortable with having the validation code in the same file as my models (as in the default AccountModels.cs file that ships with MVC2). But I have some common validations that apply to several models as well (valid email address format for example). When I cut/paste that validation to the second model that needs it, of course I get a duplicate definition error because they're in the same namespace (projectName.Models). So I thought of removing the common validations to a separate class within the namespace, expecting that all of my view models would be able to access the validations from there. Unexpectedly, the validations are no longer accessible. I've verified that they are still in the same namespace, and they are all public. I wouldn't expect that I would have to have any specific reference to them (tried adding using statement for the same namespace, but that didn't resolve it, and via the add references dialog, a project can't reference itself (makes sense). So any idea why public validations that have simply been moved to another file in the same namespace aren't visible to my models? CommonValidations.cs using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.ComponentModel; using System.ComponentModel.DataAnnotations; using System.Text.RegularExpressions; namespace ProjectName.Models { public class CommonValidations { [AttributeUsage(AttributeTargets.Field | AttributeTargets.Property, AllowMultiple = true, Inherited = true)] public sealed class EmailFormatValidAttribute : ValidationAttribute { public override bool IsValid(object value) { if (value != null) { var expression = @"^[a-zA-Z][\w\.-]*[a-zA-Z0-9]@[a-zA-Z0-9][\w\.-]*[a-zA-Z0-9]\.[a-zA-Z][a-zA-Z\.]*[a-zA-Z]$"; return Regex.IsMatch(value.ToString(), expression); } else { return false; } } } } } And here's the code that I want to use the validation from: using System; using System.Collections.Generic; using System.Linq; using System.Web; using System.ComponentModel; using System.ComponentModel.DataAnnotations; using Growums.Models; namespace ProjectName.Models { public class PrivacyModel { [Required(ErrorMessage="Required")] [EmailFormatValid(ErrorMessage="Invalid Email")] public string Email { get; set; } } }

    Read the article

  • Help with OpenSSL request using Python

    - by Ldn
    Hi i'm creating a program that has to make a request and then obtain some info. For doing that the website had done some API that i will use. There is an how-to about these API but every example is made using PHP. But my app is done using Python so i need to convert the code. here is the how-to: The request string is sealed with OpenSSL. The steps for sealing are as follows: • Random 128-bit key is created. • Random key is used to RSA-RC4 symettrically encrypt the request string. • Random key is encrypted with the public key using OpenSSL RSA asymmetrical encryption. • The encrypted request and encrypted key are each base64 encoded and placed in the appropriate fields. In PHP a full request to our API can be accomplished like so: <?php // initial request. $request = array('object' => 'Link', 'action' => 'get', 'args' => array( 'app_id' => 303612602 ) ); // encode the request in JSON $request = json_encode($request); // when you receive your profile, you will be given a public key to seal your request in. $key_pem = "-----BEGIN PUBLIC KEY----- MFwwDQYJKoZIhvcNAQEBBQADSwAwSAJBALdu5C6d2sA1Lu71NNGBEbLD6DjwhFQO VLdFAJf2rOH63rG/L78lrQjwMLZOeHEHqjaiUwCr8NVTcVrebu6ylIECAwEAAQ== -----END PUBLIC KEY-----"; // load the public key $pkey = openssl_pkey_get_public($key_pem); // seal! $newrequest and $enc_keys are passed by reference. openssl_seal($request, $enc_request, $enc_keys, array($pkey)); // then wrap the request $wrapper = array( 'profile' => 'ProfileName', 'format' => 'RSA_RC4_Sealed', 'enc_key' => base64_encode($enc_keys[0]), 'request' => base64_encode($enc_request) ); // json encode the wrapper. urlencode it as well. $wrapper = urlencode(json_encode($wrapper)); // we can send the request wrapper via the cURL extension $ch = curl_init(); curl_setopt($ch, CURLOPT_URL, 'http://api.site.com/'); curl_setopt($ch, CURLOPT_POST, 1); curl_setopt($ch, CURLOPT_POSTFIELDS, "request=$wrapper"); curl_setopt($ch, CURLOPT_RETURNTRANSFER, true); $data = curl_exec($ch); curl_close($ch); ?> Of all of that, i was able to convert "$request" and i'v also made the JSON encode. This is my code: import urllib import urllib2 import json url = 'http://api.site.com/' array = {'app_id' : "303612602"} values = { "object" : "Link", "action": "get", "args" : array } data = urllib.urlencode(values) json_data = json.dumps(data) What stop me is the sealing with OpenSSL and the publi key (that obviously i have) Using PHP OpenSSL it's so easy, but in Python i don't really know how to use it Please, help me!

    Read the article

  • WPF: Order of stretch sizing

    - by RFBoilers
    I'm creating a modal dialog window which contains three essential parts: a TextBlock containing instructions, a ContentControl for the dialog panel, and a ContentControl for the dialog buttons. Each of these parts are contained in a separate Grid row. I have some specific constraints when it comes to how the dialog should be sized. The issue I'm having is with the instructions TextBlock. I want the instructions to be as wide as the ContentControl for the dialog panel. The instructions should then wrap and grow vertically as needed. Should the instructions not be able to grow vertically, then it should begin to grow horizontally. Getting the instructions to be the width of the ContentControl and grow vertically was simple. The part I can't seem to figure out is how to get it to grow horizontally when out of vertical space. My initial thought was to create a class that extends TextBlock and override MeasureOverride. However, that method is sealed. Currently, I'm playing with the idea of have the dialog Window override MeasureOverride to calculate the available size for the instructions block. Am I missing a much simpler way of accomplishing this? Does anyone have any better ideas than this? Messing with MeasureOverride seems like it will be a lot of work. Here is some sample code to give you a general idea of how the dialog is laid out: <Window x:Class="Dialogs.DialogWindow" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" x:Name="dialogWindow" ShowInTaskbar="False" WindowStyle="None" AllowsTransparency="True" Background="Transparent" ResizeMode="NoResize" SizeToContent="WidthAndHeight" WindowStartupLocation="CenterScreen"> <Border Style="{StaticResource WindowBorderStyle}" Margin="15"> <Grid> <Grid.RowDefinitions> <RowDefinition Height="Auto"/> <RowDefinition Height="Auto"/> <RowDefinition Height="Auto"/> </Grid.RowDefinitions> <TextBlock Margin="25,5" VerticalAlignment="Top" HorizontalAlignment="Left" Text="{Binding Instructions}" TextWrapping="Wrap" Width="{Binding ElementName=panelContentControl, Path=ActualWidth, Mode=OneWay}"/> <ContentControl x:Name="panelContentControl" Grid.Row="1" Margin="25,5" Content="{Binding PanelContent}"/> <ContentControl x:Name="buttonsContentControl" Grid.Row="2" HorizontalAlignment="Right" VerticalAlignment="Center" Margin="25,5" Content="{Binding ButtonsContent}"/> </Grid> </Border> </Window>

    Read the article

  • Calling 32 bit unmanaged dlls from C# randomly failing

    - by Bert
    Hi, I'm having an issue when calling 32 bit delphi dll's from c# web site. The code generally runs fine, but occasionally I get an error Unable to load DLL '': The specified module could not be found. (Exception from HRESULT: 0x8007007E). This issue persists until I recycle the app pool for the site, and then it works fine again. On the same server, there is also a web service that is calling the same set of dlls. This web service doesn't seem to have the same issue that the web site has. Both applications are using .net framework 3.5, separate app pools on IIS. Here is the code I'm using to wrap the dlls: public sealed class Mapper { static Mapper instance = null; [DllImport("kernel32.dll")] private static extern bool SetDllDirectory(string lpPathName); private Mapper() { SetDllDirectory(ConfigManager.Path); } public static Mapper Instance { get { if (instance == null) { instance = new Mapper(); } return instance; } } public int Foo(string bar, ref double val) { return Loader.Foo(bar, ref val); } } public static class Loader { [DllImport("some.dll", CallingConvention = CallingConvention.StdCall, CharSet = CharSet.Unicode, EntryPoint = "foo")] public static extern int Foo(string bar, ref double val); } Then I call it like this: double val = 0.0; Mapper.Instance.Foo("bar", ref val); Any ideas as to why it would "randomly" Unable to load DLL '': The specified module could not be found. (Exception from HRESULT: 0x8007007E). The other problem is that I haven't been able to replicate the issue in the development environment. I thought that due to 2 applications calling the same dlls, that there could be some locks occurring. To replicate this, I created an app that spawned multiple threads and repeatedly called the 32bit dlls, and then used the web site to call these same dlls. I still couldn't replicate the issue. Some possible fixes that I can think of: Wrap the 32 bit dlls in web service (because the webservice doesn't seem to suffer from the same problem). But this may be worthless if it turns out that the web service also fails. Set up state server for the session state and periodically recycle the app pool for the site.This isn't fixing the problem, only avoiding it. Wrap the dll's in exe, and call that exe. Then I shouldn't get the same issue. But this also seems like a hacky solution. Implement the mapper class differently ? But how else should I be doing the call? The other draw back is that other applications are using this mapper, so I'd need to change there code too. Thanks

    Read the article

  • Discovering a functional algorithm from a mutable one

    - by Garrett Rowe
    This isn't necessarily a Scala question, it's a design question that has to do with avoiding mutable state, functional thinking and that sort. It just happens that I'm using Scala. Given this set of requirements: Input comes from an essentially infinite stream of random numbers between 1 and 10 Final output is either SUCCEED or FAIL There can be multiple objects 'listening' to the stream at any particular time, and they can begin listening at different times so they all may have a different concept of the 'first' number; therefore listeners to the stream need to be decoupled from the stream itself. Pseudocode: if (first number == 1) SUCCEED else if (first number >= 9) FAIL else { first = first number rest = rest of stream for each (n in rest) { if (n == 1) FAIL else if (n == first) SUCCEED else continue } } Here is a possible mutable implementation: sealed trait Result case object Fail extends Result case object Succeed extends Result case object NoResult extends Result class StreamListener { private var target: Option[Int] = None def evaluate(n: Int): Result = target match { case None => if (n == 1) Succeed else if (n >= 9) Fail else { target = Some(n) NoResult } case Some(t) => if (n == t) Succeed else if (n == 1) Fail else NoResult } } This will work but smells to me. StreamListener.evaluate is not referentially transparent. And the use of the NoResult token just doesn't feel right. It does have the advantage though of being clear and easy to use/code. Besides there has to be a functional solution to this right? I've come up with 2 other possible options: Having evaluate return a (possibly new) StreamListener, but this means I would have to make Result a subtype of StreamListener which doesn't feel right. Letting evaluate take a Stream[Int] as a parameter and letting the StreamListener be in charge of consuming as much of the Stream as it needs to determine failure or success. The problem I see with this approach is that the class that registers the listeners should query each listener after each number is generated and take appropriate action immediately upon failure or success. With this approach, I don't see how that could happen since each listener is forcing evaluation of the Stream until it completes evaluation. There is no concept here of a single number generation. Is there any standard scala/fp idiom I'm overlooking here?

    Read the article

  • How to use a separate class to validate credit card numbers in C#

    - by EvanRyan
    I have set up a class to validate credit card numbers. The credit card type and number are selected on a form in a separate class. I'm trying to figure out how to get the credit card type and number that are selected in the other class (frmPayment) in to my credit card class algorithm: public enum CardType { MasterCard, Visa, AmericanExpress } public sealed class CardValidator { public static string SelectedCardType { get; private set; } public static string CardNumber { get; private set; } private CardValidator(string selectedCardType, string cardNumber) { SelectedCardType = selectedCardType; CardNumber = cardNumber; } public static bool Validate(CardType cardType, string cardNumber) { byte[] number = new byte[16]; int length = 0; for (int i = 0; i < cardNumber.Length; i++) { if (char.IsDigit(cardNumber, i)) { if (length == 16) return false; number[length++] = byte.Parse(cardNumber[i]); //not working. find different way to parse } } switch(cardType) { case CardType.MasterCard: if(length != 16) return false; if(number[0] != 5 || number[1] == 0 || number[1] > 5) return false; break; case CardType.Visa: if(length != 16 & length != 13) return false; if(number[0] != 4) return false; break; case CardType.AmericanExpress: if(length != 15) return false; if(number[0] != 3 || (number[1] != 4 & number[1] != 7)) return false; break; } // Use Luhn Algorithm to validate int sum = 0; for(int i = length - 1; i >= 0; i--) { if(i % 2 == length % 2) { int n = number[i] * 2; sum += (n / 10) + (n % 10); } else sum += number[i]; } return (sum % 10 == 0); } }

    Read the article

< Previous Page | 5 6 7 8 9 10 11  | Next Page >