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  • PHP class function.

    - by Jordan Pagaduan
    What is wrong with this code? <?php class users { var $user_id, $f_name, $l_name, $db_host, $db_user, $db_name, $db_table; function user_input() { $this->$db_host = 'localhost'; $this->$db_user = 'root'; $this->$db_name = 'input_oop'; $this->$db_table = 'users'; } function userInput($f_name, $l_name) { $dbc = mysql_connect($this->db_host , $this->db_user, "") or die ("Cannot connect to database : " .mysql_error()); mysql_select_db($this->db_name) or die (mysql_error()); $query = "insert into $this->db_table values (NULL, \"$f_name\", \"$l_name\")"; $result = mysql_query($query); if(!$result) die (mysql_error()); $this->userID = mysql_insert_id(); mysql_close($dbc); $this->first_name = $f_name; $this->last_name = $l_name; } function userUpdate($new_f_name, $new_l_name) { $dbc = mysql_connect($this->db_host, $this->db_user, "") or die (mysql_error()); mysql_select_db($this->db_name) or die (mysql_error()); $query = "UPDATE $this->db_table set = \"$new_f_name\" , \"$new_l_name\" WHERE user_id = \"$this->user_id\""; $result = mysql_query($query); $this->f_name = $new_f_name; $this->l_name = $new_l_name; $this->user_id = $user_id; mysql_close($dbc); } function userDelete() { $dbc = mysql_connect($this->db_host, $this->db_user, "") or die (mysql_error()); mysql_select_db($this->db_name) or die (mysql_error()); $query = "DELETE FROM $this->db_table WHERE $user_id = \"$this->user_id\""; mysql_close($dbc); } } ?> The error is: Warning: mysql_connect() [function.mysql-connect]: Access denied for user 'ODBC'@'localhost' (using password: NO) in C:\xampp\htdocs\jordan_pagaduan\class.php on line 21 Cannot connect to database : Access denied for user 'ODBC'@'localhost' (using password: NO) The code cannot define this "$this->db_host" as "localhost".

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  • C++ Structure v/s Class

    - by Ankur
    Hi, Please let me know whats the difference between a C++ structure and a C++ class apart from access specifier. I have seen inheritence , polymorphism in C++ structure?

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  • Documenting class attribute

    - by Dewfy
    Following sample is taken from "Dive into python" book. class MP3FileInfo(FileInfo): "store ID3v1.0 MP3 tags" tagDataMap = ... This sample shows documenting the MP3FileInfo, but how can I add help to MP3FileInfo. tagDataMap

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  • How to see .class content in Eclipse?

    - by mac
    Sometimes, in Eclipse , i press a combination of keys which take me to the editor page that shows contents of my .class file. I never seem to be able to remember what that key combination is. Can someone please let me know?

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  • importing class and its function from another file [Python]

    - by user343934
    Hi everyone, I am having little bit problem in importing classes in python. My work flow goes like this -index.py ---class template: ------def header(): ------def body(): ------def footer(): -display.py I want to call function header(), body() and footer () in my display.py page. Will anyone make me clear about this issue in python. Thanks for your concern.

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  • C# : having a "+" in the class name ?

    - by Graveen
    Hello, class name: MyAssembly.MyClass+MyOtherClass The problem is obviously the + as separator, instead of traditionnal dot, its function, and to find official documentation to see if others separators exist Thank you in advance !

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  • ASP.NET MVC ‘Extendable-hooks’ – ControllerActionInvoker class

    - by nmarun
    There’s a class ControllerActionInvoker in ASP.NET MVC. This can be used as one of an hook-points to allow customization of your application. Watching Brad Wilsons’ Advanced MP3 from MVC Conf inspired me to write about this class. What MSDN says: “Represents a class that is responsible for invoking the action methods of a controller.” Well if MSDN says it, I think I can instill a fair amount of confidence into what the class does. But just to get to the details, I also looked into the source code for MVC. Seems like the base class Controller is where an IActionInvoker is initialized: 1: protected virtual IActionInvoker CreateActionInvoker() { 2: return new ControllerActionInvoker(); 3: } In the ControllerActionInvoker (the O-O-B behavior), there are different ‘versions’ of InvokeActionMethod() method that actually call the action method in question and return an instance of type ActionResult. 1: protected virtual ActionResult InvokeActionMethod(ControllerContext controllerContext, ActionDescriptor actionDescriptor, IDictionary<string, object> parameters) { 2: object returnValue = actionDescriptor.Execute(controllerContext, parameters); 3: ActionResult result = CreateActionResult(controllerContext, actionDescriptor, returnValue); 4: return result; 5: } I guess that’s enough on the ‘behind-the-screens’ of this class. Let’s see how we can use this class to hook-up extensions. Say I have a requirement that the user should be able to get different renderings of the same output, like html, xml, json, csv and so on. The user will type-in the output format in the url and should the get result accordingly. For example: http://site.com/RenderAs/ – renders the default way (the razor view) http://site.com/RenderAs/xml http://site.com/RenderAs/csv … and so on where RenderAs is my controller. There are many ways of doing this and I’m using a custom ControllerActionInvoker class (even though this might not be the best way to accomplish this). For this, my one and only route in the Global.asax.cs is: 1: routes.MapRoute("RenderAsRoute", "RenderAs/{outputType}", 2: new {controller = "RenderAs", action = "Index", outputType = ""}); Here the controller name is ‘RenderAsController’ and the action that’ll get called (always) is the Index action. The outputType parameter will map to the type of output requested by the user (xml, csv…). I intend to display a list of food items for this example. 1: public class Item 2: { 3: public int Id { get; set; } 4: public string Name { get; set; } 5: public Cuisine Cuisine { get; set; } 6: } 7:  8: public class Cuisine 9: { 10: public int CuisineId { get; set; } 11: public string Name { get; set; } 12: } Coming to my ‘RenderAsController’ class. I generate an IList<Item> to represent my model. 1: private static IList<Item> GetItems() 2: { 3: Cuisine cuisine = new Cuisine { CuisineId = 1, Name = "Italian" }; 4: Item item = new Item { Id = 1, Name = "Lasagna", Cuisine = cuisine }; 5: IList<Item> items = new List<Item> { item }; 6: item = new Item {Id = 2, Name = "Pasta", Cuisine = cuisine}; 7: items.Add(item); 8: //... 9: return items; 10: } My action method looks like 1: public IList<Item> Index(string outputType) 2: { 3: return GetItems(); 4: } There are two things that stand out in this action method. The first and the most obvious one being that the return type is not of type ActionResult (or one of its derivatives). Instead I’m passing the type of the model itself (IList<Item> in this case). We’ll convert this to some type of an ActionResult in our custom controller action invoker class later. The second thing (a little subtle) is that I’m not doing anything with the outputType value that is passed on to this action method. This value will be in the RouteData dictionary and we’ll use this in our custom invoker class as well. It’s time to hook up our invoker class. First, I’ll override the Initialize() method of my RenderAsController class. 1: protected override void Initialize(RequestContext requestContext) 2: { 3: base.Initialize(requestContext); 4: string outputType = string.Empty; 5:  6: // read the outputType from the RouteData dictionary 7: if (requestContext.RouteData.Values["outputType"] != null) 8: { 9: outputType = requestContext.RouteData.Values["outputType"].ToString(); 10: } 11:  12: // my custom invoker class 13: ActionInvoker = new ContentRendererActionInvoker(outputType); 14: } Coming to the main part of the discussion – the ContentRendererActionInvoker class: 1: public class ContentRendererActionInvoker : ControllerActionInvoker 2: { 3: private readonly string _outputType; 4:  5: public ContentRendererActionInvoker(string outputType) 6: { 7: _outputType = outputType.ToLower(); 8: } 9: //... 10: } So the outputType value that was read from the RouteData, which was passed in from the url, is being set here in  a private field. Moving to the crux of this article, I now override the CreateActionResult method. 1: protected override ActionResult CreateActionResult(ControllerContext controllerContext, ActionDescriptor actionDescriptor, object actionReturnValue) 2: { 3: if (actionReturnValue == null) 4: return new EmptyResult(); 5:  6: ActionResult result = actionReturnValue as ActionResult; 7: if (result != null) 8: return result; 9:  10: // This is where the magic happens 11: // Depending on the value in the _outputType field, 12: // return an appropriate ActionResult 13: switch (_outputType) 14: { 15: case "json": 16: { 17: JavaScriptSerializer serializer = new JavaScriptSerializer(); 18: string json = serializer.Serialize(actionReturnValue); 19: return new ContentResult { Content = json, ContentType = "application/json" }; 20: } 21: case "xml": 22: { 23: XmlSerializer serializer = new XmlSerializer(actionReturnValue.GetType()); 24: using (StringWriter writer = new StringWriter()) 25: { 26: serializer.Serialize(writer, actionReturnValue); 27: return new ContentResult { Content = writer.ToString(), ContentType = "text/xml" }; 28: } 29: } 30: case "csv": 31: controllerContext.HttpContext.Response.AddHeader("Content-Disposition", "attachment; filename=items.csv"); 32: return new ContentResult 33: { 34: Content = ToCsv(actionReturnValue as IList<Item>), 35: ContentType = "application/ms-excel" 36: }; 37: case "pdf": 38: string filePath = controllerContext.HttpContext.Server.MapPath("~/items.pdf"); 39: controllerContext.HttpContext.Response.AddHeader("content-disposition", 40: "attachment; filename=items.pdf"); 41: ToPdf(actionReturnValue as IList<Item>, filePath); 42: return new FileContentResult(StreamFile(filePath), "application/pdf"); 43:  44: default: 45: controllerContext.Controller.ViewData.Model = actionReturnValue; 46: return new ViewResult 47: { 48: TempData = controllerContext.Controller.TempData, 49: ViewData = controllerContext.Controller.ViewData 50: }; 51: } 52: } A big method there! The hook I was talking about kinda above actually is here. This is where different kinds / formats of output get returned based on the output type requested in the url. When the _outputType is not set (string.Empty as set in the Global.asax.cs file), the razor view gets rendered (lines 45-50). This is the default behavior in most MVC applications where-in a view (webform/razor) gets rendered on the browser. As you see here, this gets returned as a ViewResult. But then, for an outputType of json/xml/csv, a ContentResult gets returned, while for pdf, a FileContentResult is returned. Here are how the different kinds of output look like: This is how we can leverage this feature of ASP.NET MVC to developer a better application. I’ve used the iTextSharp library to convert to a pdf format. Mike gives quite a bit of detail regarding this library here. You can download the sample code here. (You’ll get an option to download once you open the link). Verdict: Hot chocolate: $3; Reebok shoes: $50; Your first car: $3000; Being able to extend a web application: Priceless.

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  • Class hierarchy problem in this social network model

    - by Gerenuk
    I'm trying to design a class system for a social network data model - basically a link/object system. Now I have roughly the following structure (simplified and only relevant methods shown) class Data: "used to handle the data with mongodb" "can link, unlink data and also return other linked data" "is basically a proxy object that only stores _id and accesses mongodb on requests" "it looks like {_id: ..., _out: [id1, id2,...], _inc: [id3, id4, ...]}" def get_node(self, id) "create a new Data object from the underlying mongodb" "each data object can potentially create a reference object to new mongo data" "this is needed when the data returns the linked objects" class Node: """ this class proxies linking calls to .data it includes additional network logic operations whereas Data only contains a basic database solution """ def __init__(self, data): "the infrastructure realization is stored as composition by an included object data" "Node bascially proxies most calls to the infrastructure object data" def get_node(self, data): "creates a new object of class Object or Link depending on data" class Object(Node): "can have multiple connections to Link" class Link(Node): "has one 'in' and one 'out' connection to an Object" This system is working, however maybe wouldn't work outside Python. Note that after reading links Now I have two questions here: 1) I want to infrastructure of the data storage to be replacable. Earlier I had Data as a superclass of Node so that it provided the neccessary calls. But (without dirty Python tricks) you cannot replace the superclass dynamically. Is using composition therefore recommended? The drawback is that I have to proxy most calls (link, unlink etc). Any thoughts? 2) The class Node contains the common method .get_node which is used to built new Object or Link instances after reading out the data. Some attribute of data decided whether the object which is only stored by id should be instantiated as an Object or Link class. The problem here is that Node needs to know about Object and Link in advance, which seems dodgy. Do you see a different solution? Both Object and Link need to instantiate one of all possible types depending on what the find in their linked data. Are there any other ideas how to implement a flexible Object/Link structure where the underlying database storage is isolated?

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  • Static / Shared Helper Functions vs Built-In Methods

    - by Nathan
    This is a simple question but a design consideration that I often run across in my day to day development work. Lets say that you have a class that represents some kinds of collection. Public Class ModifiedCustomerOrders Public Property Orders as List(Of ModifiedOrders) End Class Within this class you do all kinds of important work, such as combining many different information sources and, eventually, build the Modified Customer Orders. Now, you have different processes that consume this class, each of which needs a slightly different slice of the ModifiedCustomerOrders items. To enable this, you want to add filtering functionality. How do you go about this? Do you: Add Filtering calls to the ModifiedCustomerOrders class so that you can say: MyOrdersClass.RemoveCanceledOrders() Create a Static / Shared "tooling" class that allows you to call: OrdersFilters.RemoveCanceledOrders(MyOrders) Create an extension method to accomplish the same feat as #2 but with less typing: MyOrders.RemoveCanceledOrders() Create a "Service" method that handles the getting of Orders as appropriate to the calling function, while using one of the previous approaches "under the hood". OrdersService.GetOrdersForProcessA() Others? I tend to prefer the tooling / extension method approaches as they make testing a little bit simpler. Although I dependency inject all my sourcing data into the ModifiedCustomerOrders, having it as part of the class makes it a little bit more complicated to test. Typically, I choose to use extension methods where I am doing parameterless transformations / filters. As they get more complex, I will move it into a static class instead. Thoughts on this approach? How would you approach it?

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  • How can I have a serializable struct that wraps it's self as an int32 implicitly? in C#?

    - by firoso
    Long story short, I have a struct (see below) that contains exactly one field: private int value; I've also implemented implicit conversion operators: public static implicit operator int(Outlet val) { return val.value; } public static implicit operator Outlet(int val) { return new Outlet(val); } I've implemented all of the following : IComparable, IComparable<Cart>, IComparable<int>, IConvertible, IEquatable<Cart>, IEquatable<int>, IFormattable I'm at a point where I really have no clue why, but whenever I serialize this object, I get no value. For instance, with XmlSerialization: <Outlet /> Also, I'm not solely concerned about XmlSerialization, I'm concerned about ALL serialization (binary for instance) How can I ensure that this serializes properly? NOTE: I did this because mapping an int,int dictionary seemed rather poorly typed to me when explicit objects with validation behavior were desired.

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  • problem with PHP class function ()

    - by lusey
    hello this is my first question here and i hope you can help me .. I am trying to find a soloution of the towers of hanoi problem by three search ways (BFS-DFS-IDS) so I use "state" class whitch defined by 5 variables as here : class state { var $tower1 = array(); var $tower2 = array(); var $tower3 = array(); var $depth; var $neighbors = array(); and it also has many function one of them is getneighbors() which supposed to fill the array $neighbors with state neighbors and they are from the type "state" and here is the function : function getneighbors () { $temp=$this->copy(); $neighbor1= $this->copy(); $neighbor2= $this->copy(); $neighbor3= $this->copy(); $neighbor4= $this->copy(); $neighbor5= $this->copy(); $neighbor6= $this->copy(); if(!Empty($temp->tower1)) { if(!Empty($neighbor1->tower2)) { if(end($neighbor1->tower1) < end($neighbor1->tower2)) { array_unshift($neighbor1->tower2,array_pop($neighbor1->tower1)); array_push($neighbors,$neighbor1); }} else { array_unshift($neighbor1->tower2, array_pop($neighbor1->tower1)); array_push($neighbors,$neighbor1); } if(!Empty($neighbor2->tower3)) { if(end($neighbor2->tower1) < end($neighbor2->tower3)) { array_unshift($neighbor2->tower3, array_pop($neighbor2->tower1)); array_push($neighbors,$neighbor2); }} else { array_unshift($neighbor2->tower3,array_shift($neighbor2->tower1)); array_push($neighbors,$neighbor2); } } if(!Empty($temp->tower2)) { if(!Empty($neighbor3->tower1)) { if(end($neighbor3->tower2) < end($neighbor3->tower1)) { array_unshift($neighbor3->tower1,array_shift($neighbor3->tower2)); array_push($neighbors,$neighbor3); } } else { array_unshift($neighbor3->tower1,array_shift($neighbor3->tower2)); array_push($neighbors,$neighbor3); } if(!Empty($neighbor4->tower3)) { if(end($neighbor4->tower2) < end($neighbor4->tower3)) { array_unshift($neighbor4->tower1,array_shift($neighbor4->tower2)); array_push($neighbors,$neighbor4); } } else{ array_unshift($neighbor4->tower3,array_shift($neighbor4->tower2)); array_push($neighbors,$neighbor4); } } if(!Empty($temp->tower3)) { if(!Empty($neighbor5->tower1)) { if(end($neighbor5->tower3) < end($neighbor5->tower1)) {array_unshift($neighbor5->tower1,array_shift($neighbor5->tower3)); array_push($neighbors,$neighbor5); } } else{ array_unshift($neighbor5->tower1,array_shift($neighbor5->tower3)); array_push($neighbors,$neighbor5);} if(!Empty($neighbor6->tower2)) { if(end($neighbor6->tower3) < end($neighbor6->tower2)) { array_unshift($neighbor6->tower2,array_shift($neighbor6->tower3)); array_push($neighbors,$neighbor6); }} else{ array_unshift($neighbor6->tower2,array_shift($neighbor6->tower3)); array_push($neighbors,$neighbor6);} } return $neighbors; } note that toString and equals and copy are defined too now the problem is that when I call getneighbors() it returns an empty $neighbors array can you pleas tell me the problem ?

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  • Silverlight 4 Tools for VS 2010 and WCF RIA Services Released

    - by ScottGu
    The final release of the Silverlight 4 Tools for Visual Studio 2010 and WCF RIA Services is now available for download.  Download and Install If you already have Visual Studio 2010 installed (or the free Visual Web Developer 2010 Express), then you can install both the Silverlight 4 Tooling Support as well as WCF RIA Services support by downloading and running this setup package (note: please make sure to uninstall the preview release of the Silverlight 4 Tools for VS 2010 if you have previously installed that).  The Silverlight 4 Tools for VS 2010 package extends the Silverlight support built into Visual Studio 2010 and enables support for Silverlight 4 applications as well.  It also installs WCF RIA Services application templates and libraries: Today’s release includes the English edition of the Silverlight 4 Tooling – localized versions will be available next month for other Visual Studio languages as well. Silverlight Tooling Support Visual Studio 2010 includes rich tooling support for building Silverlight and WPF applications. It includes a WYSIWYG designer surface that enables you to easily use controls to construct UI – including the ability to take advantage of layout containers, and apply styles and resources: The VS 2010 designer enables you to leverage the rich data binding support within Silverlight and WPF, and easily wire-up bindings on controls.  The Data Sources window within Silverlight projects can be used to reference POCO objects (plain old CLR objects), WCF Services, WCF RIA Services client proxies or SharePoint Lists.  For example, let’s assume we add a “Person” class like below to our project: We could then add it to the Data Source window which will cause it to show up like below in the IDE: We can optionally customize the default UI control types that are associated for each property on the object.  For example, below we’ll default the BirthDate property to be represented by a “DatePicker” control: And then when we drag/drop the Person type from the Data Sources onto the design-surface it will automatically create UI controls that are bound to the properties of our Person class: VS 2010 allows you to optionally customize each UI binding further by selecting a control, and then right-click on any of its properties within the property-grid and pull up the “Apply Bindings” dialog: This will bring up a floating data-binding dialog that enables you to easily configure things like the binding path on the data source object, specify a format convertor, specify string-format settings, specify how validation errors should be handled, etc: In addition to providing WYSIWYG designer support for WPF and Silverlight applications, VS 2010 also provides rich XAML intellisense and code editing support – enabling a rich source editing environment. Silverlight 4 Tool Enhancements Today’s Silverlight 4 Tooling Release for VS 2010 includes a bunch of nice new features.  These include: Support for Silverlight Out of Browser Applications and Elevated Trust Applications You can open up a Silverlight application’s project properties window and click the “Enable Running Application Out of Browser” checkbox to enable you to install an offline, out of browser, version of your Silverlight 4 application.  You can then customize a number of “out of browser” settings of your application within Visual Studio: Notice above how you can now indicate that you want to run with elevated trust, with hardware graphics acceleration, as well as customize things like the Window style of the application (allowing you to build a nice polished window style for consumer applications). Support for Implicit Styles and “Go to Value Definition” Support: Silverlight 4 now allows you to define “implicit styles” for your applications.  This allows you to style controls by type (for example: have a default look for all buttons) and avoid you having to explicitly reference styles from each control.  In addition to honoring implicit styles on the designer-surface, VS 2010 also now allows you to right click on any control (or on one of it properties) and choose the “Go to Value Definition…” context menu to jump to the XAML where the style is defined, and from there you can easily navigate onward to any referenced resources.  This makes it much easier to figure out questions like “why is my button red?”: Style Intellisense VS 2010 enables you to easily modify styles you already have in XAML, and now you get intellisense for properties and their values within a style based on the TargetType of the specified control.  For example, below we have a style being set for controls of type “Button” (this is indicated by the “TargetType” property).  Notice how intellisense now automatically shows us properties for the Button control (even within the <Setter> element): Great Video - Watch the Silverlight Designer Features in Action You can see all of the above Silverlight 4 Tools for Visual Studio 2010 features (and some more cool ones I haven’t mentioned) demonstrated in action within this 20 minute Silverlight.TV video on Channel 9: WCF RIA Services Today we also shipped the V1 release of WCF RIA Services.  It is included and automatically installed as part of the Silverlight 4 Tools for Visual Studio 2010 setup. WCF RIA Services makes it much easier to build business applications with Silverlight.  It simplifies the traditional n-tier application pattern by bringing together the ASP.NET and Silverlight platforms using the power of WCF for communication.  WCF RIA Services provides a pattern to write application logic that runs on the mid-tier and controls access to data for queries, changes and custom operations. It also provides end-to-end support for common tasks such as data validation, authentication and authorization based on roles by integrating with Silverlight components on the client and ASP.NET on the mid-tier. Put simply – it makes it much easier to query data stored on a server from a client machine, optionally manipulate/modify the data on the client, and then save it back to the server.  It supports a validation architecture that helps ensure that your data is kept secure and business rules are applied consistently on both the client and middle-tiers. WCF RIA Services uses WCF for communication between the client and the server  It supports both an optimized .NET to .NET binary serialization format, as well as a set of open extensions to the ATOM format known as ODATA and an optional JavaScript Object Notation (JSON) format that can be used by any client. You can hear Nikhil and Dinesh talk a little about WCF RIA Services in this 13 minutes Channel 9 video. Putting it all Together – the Silverlight 4 Training Kit Check out the Silverlight 4 Training Kit to learn more about how to build business applications with Silverlight 4, Visual Studio 2010 and WCF RIA Services. The training kit includes 8 modules, 25 videos, and several hands-on labs that explain Silverlight 4 and WCF RIA Services concepts and walks you through building an end-to-end application with them.    The training kit is available for free and is a great way to get started. Summary I’m really excited about today’s release – as they really complete the Silverlight development story and deliver a great end to end runtime + tooling story for building applications.  All of the above features are available for use both in VS 2010 as well as the free Visual Web Developer 2010 Express Edition – making it really easy to get started building great solutions. Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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  • Visual Studio 2010 Extension Manager (and the new VS 2010 PowerCommands Extension)

    This is the twenty-third in a series of blog posts Im doing on the VS 2010 and .NET 4 release. Todays blog post covers some of the extensibility improvements made in VS 2010 as well as a cool new "PowerCommands for Visual Studio 2010 extension that Microsoft just released (and which can be downloaded and used for free). [In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu] Extensibility in VS 2010 VS 2010...Did you know that DotNetSlackers also publishes .net articles written by top known .net Authors? We already have over 80 articles in several categories including Silverlight. Take a look: here.

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  • Mutable class as a child of an immutable class

    - by deamon
    I want to have immutable Java objects like this (strongly simplyfied): class Immutable { protected String name; public Immutable(String name) { this.name = name; } public String getName() { return name; } } In some cases the object should not only be readable but mutable, so I could add mutability through inheritance: public class Mutable extends Immutable { public Mutable(String name) { super(name); } public void setName(String name) { super.name = name; } } While this is technically fine, I wonder if it conforms with OOP and inheritance that mutable is also of type immutable. I want to avoid the OOP crime to throw UnsupportedOperationException for immutable object, like the Java collections API does. What do you think? Any other ideas?

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  • VS 2010 Debugger Improvements (BreakPoints, DataTips, Import/Export)

    - by ScottGu
    This is the twenty-first in a series of blog posts I’m doing on the VS 2010 and .NET 4 release.  Today’s blog post covers a few of the nice usability improvements coming with the VS 2010 debugger.  The VS 2010 debugger has a ton of great new capabilities.  Features like Intellitrace (aka historical debugging), the new parallel/multithreaded debugging capabilities, and dump debuging support typically get a ton of (well deserved) buzz and attention when people talk about the debugging improvements with this release.  I’ll be doing blog posts in the future that demonstrate how to take advantage of them as well.  With today’s post, though, I thought I’d start off by covering a few small, but nice, debugger usability improvements that were also included with the VS 2010 release, and which I think you’ll find useful. Breakpoint Labels VS 2010 includes new support for better managing debugger breakpoints.  One particularly useful feature is called “Breakpoint Labels” – it enables much better grouping and filtering of breakpoints within a project or across a solution.  With previous releases of Visual Studio you had to manage each debugger breakpoint as a separate item. Managing each breakpoint separately can be a pain with large projects and for cases when you want to maintain “logical groups” of breakpoints that you turn on/off depending on what you are debugging.  Using the new VS 2010 “breakpoint labeling” feature you can now name these “groups” of breakpoints and manage them as a unit. Grouping Multiple Breakpoints Together using a Label Below is a screen-shot of the breakpoints window within Visual Studio 2010.  This lists all of the breakpoints defined within my solution (which in this case is the ASP.NET MVC 2 code base): The first and last breakpoint in the list above breaks into the debugger when a Controller instance is created or released by the ASP.NET MVC Framework. Using VS 2010, I can now select these two breakpoints, right-click, and then select the new “Edit labels…” menu command to give them a common label/name (making them easier to find and manage): Below is the dialog that appears when I select the “Edit labels” command.  We can use it to create a new string label for our breakpoints or select an existing one we have already defined.  In this case we’ll create a new label called “Lifetime Management” to describe what these two breakpoints cover: When we press the OK button our two selected breakpoints will be grouped under the newly created “Lifetime Management” label: Filtering/Sorting Breakpoints by Label We can use the “Search” combobox to quickly filter/sort breakpoints by label.  Below we are only showing those breakpoints with the “Lifetime Management” label: Toggling Breakpoints On/Off by Label We can also toggle sets of breakpoints on/off by label group.  We can simply filter by the label group, do a Ctrl-A to select all the breakpoints, and then enable/disable all of them with a single click: Importing/Exporting Breakpoints VS 2010 now supports importing/exporting breakpoints to XML files – which you can then pass off to another developer, attach to a bug report, or simply re-load later.  To export only a subset of breakpoints, you can filter by a particular label and then click the “Export breakpoint” button in the Breakpoints window: Above I’ve filtered my breakpoint list to only export two particular breakpoints (specific to a bug that I’m chasing down).  I can export these breakpoints to an XML file and then attach it to a bug report or email – which will enable another developer to easily setup the debugger in the correct state to investigate it on a separate machine.  Pinned DataTips Visual Studio 2010 also includes some nice new “DataTip pinning” features that enable you to better see and track variable and expression values when in the debugger.  Simply hover over a variable or expression within the debugger to expose its DataTip (which is a tooltip that displays its value)  – and then click the new “pin” button on it to make the DataTip always visible: You can “pin” any number of DataTips you want onto the screen.  In addition to pinning top-level variables, you can also drill into the sub-properties on variables and pin them as well.  Below I’ve “pinned” three variables: “category”, “Request.RawUrl” and “Request.LogonUserIdentity.Name”.  Note that these last two variable are sub-properties of the “Request” object.   Associating Comments with Pinned DataTips Hovering over a pinned DataTip exposes some additional UI within the debugger: Clicking the comment button at the bottom of this UI expands the DataTip - and allows you to optionally add a comment with it: This makes it really easy to attach and track debugging notes: Pinned DataTips are usable across both Debug Sessions and Visual Studio Sessions Pinned DataTips can be used across multiple debugger sessions.  This means that if you stop the debugger, make a code change, and then recompile and start a new debug session - any pinned DataTips will still be there, along with any comments you associate with them.  Pinned DataTips can also be used across multiple Visual Studio sessions.  This means that if you close your project, shutdown Visual Studio, and then later open the project up again – any pinned DataTips will still be there, along with any comments you associate with them. See the Value from Last Debug Session (Great Code Editor Feature) How many times have you ever stopped the debugger only to go back to your code and say: $#@! – what was the value of that variable again??? One of the nice things about pinned DataTips is that they keep track of their “last value from debug session” – and you can look these values up within the VB/C# code editor even when the debugger is no longer running.  DataTips are by default hidden when you are in the code editor and the debugger isn’t running.  On the left-hand margin of the code editor, though, you’ll find a push-pin for each pinned DataTip that you’ve previously setup: Hovering your mouse over a pinned DataTip will cause it to display on the screen.  Below you can see what happens when I hover over the first pin in the editor - it displays our debug session’s last values for the “Request” object DataTip along with the comment we associated with them: This makes it much easier to keep track of state and conditions as you toggle between code editing mode and debugging mode on your projects. Importing/Exporting Pinned DataTips As I mentioned earlier in this post, pinned DataTips are by default saved across Visual Studio sessions (you don’t need to do anything to enable this). VS 2010 also now supports importing/exporting pinned DataTips to XML files – which you can then pass off to other developers, attach to a bug report, or simply re-load later. Combined with the new support for importing/exporting breakpoints, this makes it much easier for multiple developers to share debugger configurations and collaborate across debug sessions. Summary Visual Studio 2010 includes a bunch of great new debugger features – both big and small.  Today’s post shared some of the nice debugger usability improvements. All of the features above are supported with the Visual Studio 2010 Professional edition (the Pinned DataTip features are also supported in the free Visual Studio 2010 Express Editions)  I’ll be covering some of the “big big” new debugging features like Intellitrace, parallel/multithreaded debugging, and dump file analysis in future blog posts.  Hope this helps, Scott P.S. In addition to blogging, I am also now using Twitter for quick updates and to share links. Follow me at: twitter.com/scottgu

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  • UiElement from abstract class

    - by plotnick
    I placed a control into a grid. let's say the control is derived from public class 'ButBase' which is derived in its turn from System.Windows.Controls.Button. The code normally compiles and app works just fine. But there's something really annoying. When you try to switch to xaml-design tab it will say 'The document root element is not supported by the visual designer', which is normal and I'm totally okay with that, but the thing is, that all the xaml code is underlined and VS2010 says: 'Cannot create an instance of ButBase' although still normally compiles and able to run. I've tried the same code in VS2008, it said that needs to see a public parameterless constructor in the ButBase, and even after I put one it showed the same error. What do I miss here?

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  • UiElement based on another class

    - by plotnick
    I placed a control into a grid. let's say the control is derived from public class 'ButBase' which is derived in its turn from System.Windows.Controls.Button. The code normally compiles and app works just fine. But there's something really annoying. When you try to switch to xaml-design tab it will say 'The document root element is not supported by the visual designer', which is normal and I'm totally okay with that, but the thing is, that all the xaml code is underlined and VS2010 says: 'Cannot create an instance of ButBase' although still normally compiles and able to run. I've tried the same code in VS2008, it said that needs to see a public parameterless constructor in the ButBase, and even after I put one it showed the same error. What do I miss here?

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  • Flash AS3 undefined property MouseEvent in document class

    - by Lee
    Hi guys, this is my first time trying to use document classes in AS3 and im struggling. I am trying to add event listeners to a 2 levels deep movie clip, waiting for a click however i am getting the following error. ERROR: Access of undefined property MouseEvent package { import flash.display.MovieClip; import flash.media.Sound; import flash.media.SoundChannel; public class game extends MovieClip { public var snd_state = true; public function game() { ui_setup(); } public function ui_setup() { ui_mc.toggleMute_mc.addEventListener(MouseEvent.CLICK, snd_toggle); } public function snd_toggle(MouseEvent) { // 0 = No Sound, 1 = Full Sound trace("Toggle"); } } }

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  • objective-c Derived class may not respond to base class method

    - by zadam
    Hi, I have derived from a 3rd party class, and when I attempt to call a method in the base class, I get the x may not respond to y compiler warning. How can I remove the warning? Repro: @interface ThirdPartyBaseClass : NSObject {} +(id)build; -(void)doStuff; @end @implementation ThirdPartyBaseClass +(id) build{ return [[[self alloc] init] autorelease]; } -(void)doStuff{ } @end @interface MyDerivedClass : ThirdPartyBaseClass {} +(id)buildMySelf; @end @implementation MyDerivedClass +(id)buildMySelf{ self = [ThirdPartyBaseClass build]; [self doStuff]; // compiler warning here - 'MyDerivedClass' may not respond to '+doStuff' return self; } @end Thanks!

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