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  • UndoRedo on Nodes

    - by Geertjan
    When a change is made to the property in the Properties Window, below, the undo/redo functionality becomes enabled: When undo/redo are invoked, e.g., via the buttons in the toolbar, the display name of the node changes accordingly. The only problem I have is that the buttons only become enabled when the Person Window is selected, not when the Properties Window is selected, which would be desirable. Here's the Person object: public class Person implements PropertyChangeListener {     private String name;     public static final String PROP_NAME = "name";     public Person(String name) {         this.name = name;     }     public String getName() {         return name;     }     public void setName(String name) {         String oldName = this.name;         this.name = name;         propertyChangeSupport.firePropertyChange(PROP_NAME, oldName, name);     }     private transient final PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);     public void addPropertyChangeListener(PropertyChangeListener listener) {         propertyChangeSupport.addPropertyChangeListener(listener);     }     public void removePropertyChangeListener(PropertyChangeListener listener) {         propertyChangeSupport.removePropertyChangeListener(listener);     }     @Override     public void propertyChange(PropertyChangeEvent evt) {         propertyChangeSupport.firePropertyChange(evt);     } } And here's the Node with UndoRedo enablement: public class PersonNode extends AbstractNode implements UndoRedo.Provider, PropertyChangeListener {     private UndoRedo.Manager manager = new UndoRedo.Manager();     private boolean undoRedoEvent;     public PersonNode(Person person) {         super(Children.LEAF, Lookups.singleton(person));         person.addPropertyChangeListener(this);         setDisplayName(person.getName());     }     @Override     protected Sheet createSheet() {         Sheet sheet = Sheet.createDefault();         Sheet.Set set = Sheet.createPropertiesSet();         set.put(new NameProperty(getLookup().lookup(Person.class)));         sheet.put(set);         return sheet;     }     @Override     public void propertyChange(PropertyChangeEvent evt) {         if (evt.getPropertyName().equals(Person.PROP_NAME)) {             firePropertyChange(evt.getPropertyName(), evt.getOldValue(), evt.getNewValue());         }     }     public void fireUndoableEvent(String property, Person source, Object oldValue, Object newValue) {         manager.addEdit(new MyAbstractUndoableEdit(source, oldValue, newValue));     }     @Override     public UndoRedo getUndoRedo() {         return manager;     }     @Override     public String getDisplayName() {         Person p = getLookup().lookup(Person.class);         if (p != null) {             return p.getName();         }         return super.getDisplayName();     }     private class NameProperty extends PropertySupport.ReadWrite<String> {         private Person p;         public NameProperty(Person p) {             super("name", String.class, "Name", "Name of Person");             this.p = p;         }         @Override         public String getValue() throws IllegalAccessException, InvocationTargetException {             return p.getName();         }         @Override         public void setValue(String newValue) throws IllegalAccessException, IllegalArgumentException, InvocationTargetException {             String oldValue = p.getName();             p.setName(newValue);             if (!undoRedoEvent) {                 fireUndoableEvent("name", p, oldValue, newValue);                 fireDisplayNameChange(oldValue, newValue);             }         }     }     class MyAbstractUndoableEdit extends AbstractUndoableEdit {         private final String oldValue;         private final String newValue;         private final Person source;         private MyAbstractUndoableEdit(Person source, Object oldValue, Object newValue) {             this.oldValue = oldValue.toString();             this.newValue = newValue.toString();             this.source = source;         }         @Override         public boolean canRedo() {             return true;         }         @Override         public boolean canUndo() {             return true;         }         @Override         public void undo() throws CannotUndoException {             undoRedoEvent = true;             source.setName(oldValue.toString());             fireDisplayNameChange(oldValue, newValue);             undoRedoEvent = false;         }         @Override         public void redo() throws CannotUndoException {             undoRedoEvent = true;             source.setName(newValue.toString());             fireDisplayNameChange(oldValue, newValue);             undoRedoEvent = false;         }     } } Does anyone out there know how to have the Undo/Redo functionality enabled when the Properties Window is selected?

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  • Xcode workspace with Unity3D as a sub-project?

    - by Di Wu
    Let's say we're developing a 2D game with Cocos2d-iPhone and UIKit and CoreAnimation. But we're also considering leveraging the 3D capabilities of Unity 3D. Is it possible that we add the Unity3D-generated Xcode project as a sub-project into the workspace and expose the 3D UI element as some kind of UIView subclass so that the native UIKit and CoreAnimation code could use them without the need to mess up with their underlying Unity3D implementation?

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  • Is there a language where collections can be used as objects without altering the behavior?

    - by Dokkat
    Is there a language where collections can be used as objects without altering the behavior? As an example, first, imagine those functions work: function capitalize(str) //suppose this *modifies* a string object capitalizing it function greet(person): print("Hello, " + person) capitalize("pedro") >> "Pedro" greet("Pedro") >> "Hello, Pedro" Now, suppose we define a standard collection with some strings: people = ["ed","steve","john"] Then, this will call toUpper() on each object on that list people.toUpper() >> ["Ed","Steve","John"] And this will call greet once for EACH people on the list, instead of sending the list as argument greet(people) >> "Hello, Ed" >> "Hello, Steve" >> "Hello, John"

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  • Execute TSQL statement with ExecuteStoreQuery in entity framework 4.0

    - by Jalpesh P. Vadgama
    I was playing with entity framework in recent days and I was searching something that how we can execute TSQL statement in entity framework. And I have found one great way to do that with entity framework ‘ExecuteStoreQuery’ method. It’s executes a TSQL statement against data source given enity framework context and returns strongly typed result. You can find more information about ExcuteStoreQuery from following link. http://msdn.microsoft.com/en-us/library/dd487208.aspx So let’s examine how it works. So Let’s first create a table against which we are going to execute TSQL statement. So I have added a SQL Express database as following. Now once we are done with adding a database let’s add a table called Client like following. Here you can see above Client table is very simple. There are only two fields ClientId and ClientName where ClientId is primary key and ClientName is field where we are going to store client name. Now it’s time to add some data to the table. So I have added some test data like following. Now it’s time to add entity framework model class. So right click project->Add new item and select ADO.NET entity model as following. After clicking on add button a wizard will start it will ask whether we need to create model classes from database or not but we already have our client table ready so I have selected generate from database as following. Once you process further in wizard it will be presented a screen where we can select the our table like following. Now once you click finish it will create model classes with for us. Now we need a gridview control where we need to display those data. So in Default.aspx page I have added a grid control like following. <%@ Page Title="Home Page" Language="C#" MasterPageFile="~/Site.master" AutoEventWireup="true" CodeBehind="Default.aspx.cs" Inherits="EntityFramework._Default" %> <asp:Content ID="HeaderContent" runat="server" ContentPlaceHolderID="HeadContent"> </asp:Content> <asp:Content ID="BodyContent" runat="server" ContentPlaceHolderID="MainContent"> <h2> Welcome to ASP.NET! </h2> <p> To learn more about ASP.NET visit <a href="http://www.asp.net" title="ASP.NET Website">www.asp.net</a>. </p> <p> You can also find <a href="http://go.microsoft.com/fwlink/?LinkID=152368&amp;clcid=0x409" title="MSDN ASP.NET Docs">documentation on ASP.NET at MSDN</a>. <asp:GridView ID="grdClient" runat="server"> </asp:GridView> </p> </asp:Content> Now once we are done with adding Gridview its time to write code for server side. So I have written following code in Page_load event of default.aspx page. protected void Page_Load(object sender, EventArgs e) { if (!Page.IsPostBack) { using (var context = new EntityFramework.TestEntities()) { ObjectResult<Client> result = context.ExecuteStoreQuery<Client>("Select * from Client"); grdClient.DataSource = result; grdClient.DataBind(); } } } Here in the above code you can see that I have written create a object of our entity model and then with the help of the ExecuteStoreQuery method I have execute a simple select TSQL statement which will return a object result. I have bind that object result with gridview to display data. So now we are done with coding.So let’s run application in browser. Following is output as expected. That’s it. Hope you like it. Stay tuned for more..Till then happy programming.

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  • How do I clean build and installs, ie un-build?

    - by Kaustubh P
    I have installed and downloaded and built mongodb, and just one works. $ mongo mongo: error while loading shared libraries: libmozjs.so: cannot open shared object file: No such file or directory $ /opt/mongo/bin/mongo /opt/mongo/bin/mongo: error while loading shared libraries: libboost_system-mt.so.1.38.0: cannot open shared object file: No such file or directory $ /usr/bin/mongo MongoDB shell version: 1.6.5 connecting to: test > I can remove the installation via apt-get. But how do I remove all things mongo that were built with make, and get a clean system? I followed this guide to build and install mongodb. Thanks.

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  • Dependency Injection/IoC container practices when writing frameworks

    - by Dave Hillier
    I've used various IoC containers (Castle.Windsor, Autofac, MEF, etc) for .Net in a number of projects. I have found they tend to encourage a number of bad practices. Are there any established practices for IoC container use, particularly when providing a platform/framework? My aim as a framework writer is to make code as simple and as easy to use as possible. I'd rather write one line of code to construct an object than ten or even just two. For example, a couple of code smells that I've noticed and don't have good suggestions to: Large number of parameters (5) for constructors. Creating services tends to be complex; all of the dependencies are injected via the constructor - despite the fact that the components are rarely optional (except for maybe in testing). Lack of private and internal classes; this one may be a specific limitation of using C# and Silverlight, but I'm interested in how it is solved. It's difficult to tell what a frameworks interface is if all the classes are public; it allows me access to private parts that I probably shouldnt touch. Coupling the object lifecycle to the IoC container. It is often difficult to manually construct the dependencies required to create objects. Object lifecycle is too often managed by the IoC framework. I've seen projects where most classes are registered as Singletons. You get a lack of explicit control and are also forced to manage the internals (it relates to the above point, all classes are public and you have to inject them). For example, .Net framework has many static methods. such as, DateTime.UtcNow. Many times I have seen this wrapped and injected as a construction parameter. Depending on concrete implementation makes my code hard to test. Injecting a dependency makes my code hard to use - particularly if the class has many parameters. How do I provide both a testable interface, as well as one that is easy to use? What are the best practices?

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  • Coding different states in Adventure Games

    - by Cardin
    I'm planning out an adventure game, and can't figure out what's the right way to implement the behaviour of a level depending on state of story progression. My single-player game features a huge world where the player has to interact with people in a town at various points in the game. However, depending on story progression, different things would be presented to the player, for e.g. the Guild Leader will change locations from the town square to various locations around the city; Doors would only unlock at certain times of the day after finishing a particular routine; Different cut-screen/trigger events happen only after a particular milestone has been reached. I naively thought of using a switch{} statement initially to decide what the NPC should say or which he could be found at, and making quest objectives interact-able only after checking a global game_state variable's condition. But I realised I would quickly run into a lot of different game states and switch-cases in order to change the behaviour of an object. That switch statement would also be massively hard to debug, and I guess it might also be hard to use in a level editor. So I thought, instead of having a single object with multiple states, maybe I should have multiple instances of the same object, with a single state. That way, if I use something like a level editor, I can put an instance of the NPC at all the different locations he could ever appear at, and also an instance for each conversation state he has. But that means there'll be a lot of inactive, invisible game objects floating around the level, which might be trouble for memory, or simply hard to see in a level editor, i don't know. Or simply, make an identical, but separate level for each game state. This feels the cleanest and bug-free way to do things, but it feels like massive manual work making sure each version of the level is really identical to each other. All my methods feel so inefficient, so to recap my question, is there a better or standardised way to implement behaviour of a level depending on state of story progression? PS: I don't have a level editor yet - thinking of using something like JME SDK or making my own.

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  • CodePlex Daily Summary for Saturday, June 09, 2012

    CodePlex Daily Summary for Saturday, June 09, 2012Popular ReleasesARCBots API Program: ARCBots API Program v3 STABLE: Stable Release, you can find the update notes in the source code.Microsoft SQL Server Product Samples: Database: AdventureWorks Sample Reports 2008 R2: AdventureWorks Sample Reports 2008 R2.zip contains several reports include Sales Reason Comparisons SQL2008R2.rdl which uses Adventure Works DW 2008R2 as a data source reference. For more information, go to Sales Reason Comparisons report.RULI Chain Code Image Generator: RULI Chain Code BW Image Generator v. 0.4: added features: - 3x3 bitmask support - 7x7 bitmask support - app icon added some refactoring for later library-creationThe Chronicles of Asku: Alpha Test v1.1: Welcome to the Chronicles of Asku alpha test. The current state of the game is 2 tomb floors, level 10 cap, and almost all core systems in the game, excluding a store that you buy armor in. This is just a test for downloading the game, and severe bug hunts... INSTRUCTIONS: When you download the folder, right click within the folder and select EXTRACT ALL Run Setup.exe Follow any on screen instructions DO NOT TRY TO LOAD A CHARACTER IF YOU HAVE NEVER SAVED ONE BEFORE Patch 1.1 -Added a...Json.NET: Json.NET 4.5 Release 7: Fix - Fixed Metro build to pass Windows Application Certification Kit on Windows 8 Release Preview Fix - Fixed Metro build error caused by an anonymous type Fix - Fixed ItemConverter not being used when serializing dictionaries Fix - Fixed an incorrect object being passed to the Error event when serializing dictionaries Fix - Fixed decimal properties not being correctly ignored with DefaultValueHandlingLINQ Extensions Library: 1.0.3.0: New to release 1.0.3.0:Combinatronics: Combinations (unique) Combinations (with repetition) Permutations (unique) Permutations (with repetition) Convert jagged arrays to fixed multidimensional arrays Convert fixed multidimensional arrays to jagged arrays ElementAtMax ElementAtMin ElementAtAverage New set of array extension (1.0.2.8):Rotate Flip Resize (maintaing data) Split Fuse Replace Append and Prepend extensions (1.0.2.7) IndexOf extensions (1.0.2.7) Ne...Audio Pitch & Shift: Audio Pitch And Shift 4.5.0: Added Instruments tab for modules Open folder content feature Some bug fixesPython Tools for Visual Studio: 1.5 Beta 1: We’re pleased to announce the release of Python Tools for Visual Studio 1.5 Beta. Python Tools for Visual Studio (PTVS) is an open-source plug-in for Visual Studio which supports programming with the Python language. PTVS supports a broad range of features including: • Supports CPython, IronPython, Jython and PyPy • Python editor with advanced member, signature intellisense and refactoring • Code navigation: “Find all refs”, goto definition, and object browser • Local and remote debugging •...Circuit Diagram: Circuit Diagram 2.0 Beta 1: New in this release: Automatically flip components when placing Delete components using keyboard delete key Resize document Document properties window Print document Recent files list Confirm when exiting with unsaved changes Thumbnail previews in Windows Explorer for CDDX files Show shortcut keys in toolbox Highlight selected item in toolbox Zoom using mouse scroll wheel while holding down ctrl key Plugin support for: Custom export formats Custom import formats Open...Umbraco CMS: Umbraco CMS 5.2 Beta: The future of Umbracov5 represents the future architecture of Umbraco, so please be aware that while it's technically superior to v4 it's not yet on a par feature or performance-wise. What's new? For full details see our http://progress.umbraco.org task tracking page showing all items complete for 5.2. In a nutshellPackage Builder Starter Kits Dynamic Extension Methods Querying / IsHelpers Friendly alt template URLs Localization Various bug fixes / performance enhancements Gett...JayData - The cross-platform HTML5 data-management library for JavaScript: JayData 1.0.5: JayData is a unified data access library for JavaScript developers to query and update data from different sources like WebSQL, IndexedDB, OData, Facebook or YQL. See it in action in this 6 minutes video New features in JayData 1.0.5http://jaydata.org/blog/jaydata-1.0.5-is-here-with-authentication-support-and-more http://jaydata.org/blog/release-notes Sencha Touch 2 module (read-only)This module can be used to bind data retrieved by JayData to Sencha Touch 2 generated user interface. (exam...32feet.NET: 3.5: This version changes the 32feet.NET library (both desktop and NETCF) to use .NET Framework version 3.5. Previously we compiled for .NET v2.0. There are no code changes from our version 3.4. See the 3.4 release for more information. Changes due to compiling for .NET 3.5Applications should be changed to use NET/NETCF v3.5. Removal of class InTheHand.Net.Bluetooth.AsyncCompletedEventArgs, which we provided on NETCF. We now just use the standard .NET System.ComponentModel.AsyncCompletedEvent...DotNetNuke® Links: 06.02.01: Added new DNN 6.2.0 beta social feature "friends" BugfixesApplication Architecture Guidelines: Application Architecture Guidelines 3.0.7: 3.0.7Jolt Environment: Jolt v2 Stable: Many new features. Follow development here for more information: http://www.rune-server.org/runescape-development/rs-503-client-server/projects/298763-jolt-environment-v2.html Setup instructions in downloadSharePoint Euro 2012 - UEFA European Football Predictor: havivi.euro2012.wsp (1.5): New fetures:Multilingual Support Max users property in Standings Web Part Games time zone change (UTC +1) bug fix - Version 1.4 locking problem http://euro2012.codeplex.com/discussions/358262 bug fix - Field Title not found (v.1.3) German SP http://euro2012.codeplex.com/discussions/358189#post844228 Bug fix - Access is denied.for users with contribute rights Bug fix - Installing on non-English version of SharePoint Bug fix - Title Rules Installing SharePoint Euro 2012 PredictorSharePoint E...myManga: myManga v1.0.0.4: ChangeLogUpdating from Previous Version: Extract contents of Release - myManga v1.0.0.4.zip to previous version's folder. Replaces: myManga.exe BakaBox.dll CoreMangaClasses.dll Manga.dll Plugins/MangaReader.manga.dll Plugins/MangaFox.manga.dll Plugins/MangaHere.manga.dll Plugins/MangaPanda.manga.dllMVVM Light Toolkit: V4RC (binaries only) including Windows 8 RP: This package contains all the latest DLLs for MVVM Light V4 RC. It includes the DLLs for Windows 8 Release Preview. An updated Nuget package is also available at http://nuget.org/packages/MvvmLightLibsPreviewExtAspNet: ExtAspNet v3.1.7: +2012-06-03 v3.1.7 -?????????BUG,??????RadioButtonList?,AJAX????????BUG(swtseaman、????)。 +?Grid?BoundField、HyperLinkField、LinkButtonField、WindowField??HtmlEncode?HtmlEncodeFormatString(TiDi)。 -HtmlEncode?HtmlEncodeFormatString??????true,??????HTML????????。 -??????Asp.Net??GridView?BoundField?????????。 -http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.boundfield.htmlencode -?Grid?HyperLinkField、WindowField??UrlEncode??,????URL??(???true)。 -?????????????,?????????????...LiveChat Starter Kit: LCSK v1.5.2: New features: Visitor location (City - Country) from geo-location Pass configuration via javascript for the chat box New visitor identification (no more using the IP address as visitor identification) To update from 1.5.1 Run the /src/1.5.2-sql-updates.txt SQL script to update your database tables. If you have it installed via NuGet, simply update your package and the file will be included so you can run the update script. New installation The easiest way to add LCSK to your app is by...New ProjectsAdvanceWars: Advance Wars For NetARCBots API Program: This is a simple API program designed for quick use for the ARCBots API.AutoUpdaterdotNET: AutoUpdater.NET is a class library that allows .net developers to easily add auto update functionality to their project.C++ AMP Conformance Test Suite: C++ AMP Conformance Test Suite contains a set of tests to aid in verifying compiler, library, and runtime behaviors as specified in the C++ AMP open specification. DynamicObjectProxy: DOP (Dynamic Object Proxy) é uma biblioteca que permite que qualquer método de qualquer objeto possa ser interceptado através de um proxy dinâmico. Ao interceptar um método, pode-se decorar o objeto, alterando ou recuperando informações sobre o seu comportamento. Extremamente útil para logs, verificações de transações, etc. DOP (Dynamic Object Proxy) is a library that contains classes that makes it possible that any method of any object can be intercepted by a dynamic proxy. By interceptin...EAIP: ???????? Flatland: Artificial life, or A-Life, is a broad and ever emerging field that has found its applications in almost any field: economics, medicine, traffic planning, shopping habits, patterns in music. And it is evident that work with modelling logical life in artificial environments is a necessity for the future software developer. Abbots novella "Flatland: A Romance of Many Dimensions" describes the two dimensional world "Flatland", where life is geometrical shapes that have human-like emotions, but...GameAudioSystem: Simple Audio Game System written with OpenAL to be used with Ogre3D.HyperionSS2P - Simple scan to pdf solution: Simple scan to pdf solution.Issue Impala: Issue Impala is a powerful and elegant issue tracker.KoekyGL Wrapper: A .net wrapper for OpenGL aimed at making it easy to use OpenGL.Marik Sample Project: This is a sample by KitMongoDB Managment Client: Development MongoDB Web client. HTML 5 jQuery. One page web application. When Windows 8 metro is released then Metro style application To.MongoDB.Dynamic: MongoDB.Dynamic is a personal project that I’ve started when I was developing my first application targeting MongoDB as DBMS, using the “official driver” MongoDB.Driver, supported by 10gen. The objective is to provide a lightweight library with some interesting features that speed up development for desktop/web applications that accesses MongoDB databases. MongoDB.Dynamic is oriented to interfaces. You don’t need to create concrete classes of your entities, all you need to do is setup your...My Google Workspace: An easy way to create documents search at Google and read your emails and Much moreqzgfjava: git????,?android??“??”???SP Sticky Notes: SP Sticky Notes allows your users to add sticky notes to a page on your SharePoint site.Weather3: It's Metro Style AppXNA Scumm: This is a rewrite of the ScummVM engine using XNA. ScummVM is an engine that runs old school LucasArts graphical adventure games. It is written completely in C# and the first version will run on PC and Xbox 360. A Windows phone version will probably follow. Of course, you will need to own the original games in order to use it. I will start my work by The Secret of Monkey Island, more specifically the VGA CD version. Monkey Island 2: LeChuck's Revenge and Indiana Jones 4 and Fate of Atl...YoG Community Game: This project is a game, being developed by several members of the Yogscast Community Forums. It is a top-down shooter, based around the protagonist 'Joe', and his adventures through TV shows every day.

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  • Interop effects by resolving and instantiating types with ArcObjects

    - by Marko Apfel
    Problem this code does not work Type t = typeof(ESRI.ArcGIS.Framework.AppRefClass); System.Object obj = Activator.CreateInstance(t); but yet this code Type t = Type.GetTypeFromCLSID(typeof(ESRI.ArcGIS.Framework.AppRefClass).GUID); System.Object obj = Activator.CreateInstance(t); Reason In the first variant the runtime tries to cast to AppRefClass . This is not possible. And in the second one, the runtime does not knows anything about AppRefClass. So it leave it as IUnknown.   (originally communicated by my co-worker Ralf)

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  • Some notes on Reflector 7

    - by CliveT
    Both Bart and I have blogged about some of the changes that we (and other members of the team) have made to .NET Reflector for version 7, including the new tabbed browsing model, the inclusion of Jason Haley's PowerCommands add-in and some improvements to decompilation such as handling iterator blocks. The intention of this blog post is to cover all of the main new features in one place, and to describe the three new editions of .NET Reflector 7. If you'd simply like to try out the latest version of the beta for yourself you can do so here. Three new editions .NET Reflector 7 will come in three new editions: .NET Reflector .NET Reflector VS .NET Reflector VSPro The first edition is just the standalone Windows application. The latter two editions include the Windows application, but also add the power of Reflector into Visual Studio so that you can save time switching tools and quickly get to the bottom of a debugging issue that involves third-party code. Let's take a look at some of the new features in each edition. Tabbed browsing .NET Reflector now has a tabbed browsing model, in which the individual tabs have independent histories. You can open a new tab to view the selected object by using CTRL+CLICK. I've found this really useful when I'm investigating a particular piece of code but then want to focus on some other methods that I find along the way. For version 7, we wanted to implement the basic idea of tabs to see whether it is something that users will find helpful. If it is something that enhances productivity, we will add more tab-based features in a future version. PowerCommands add-in We have also included Jason Haley's PowerCommands add-in as part of version 7. This add-in provides a number of useful commands, including support for opening .xap files and extracting the constituent assemblies, and a query editor that allows C# queries to be written and executed against the Reflector object model . All of the PowerCommands features can be turned on from the options menu. We will be really interested to see what people are finding useful for further integration into the main tool in the future. My personal favourite part of the PowerCommands add-in is the query editor. You can set up as many of your own queries as you like, but we provide 25 to get you started. These do useful things like listing all extension methods in a given assembly, and displaying other lower-level information, such as the number of times that a given method uses the box IL instruction. These queries can be extracted and then executed from the 'Run Query' context menu within the assembly explorer. Moreover, the queries can be loaded, modified, and saved using the built-in editor, allowing very specific user customization and sharing of queries. The PowerCommands add-in contains many other useful utilities. For example, you can open an item using an external application, work with enumeration bit flags, or generate assembly binding redirect files. You can see Bart's earlier post for a more complete list. .NET Reflector VS .NET Reflector VS adds a brand new Reflector object browser into Visual Studio to save you time opening .NET Reflector separately and browsing for an object. A 'Decompile and Explore' option is also added to the context menu of references in the Solution Explorer, so you don't need to leave Visual Studio to look through decompiled code. We've also added some simple navigation features to allow you to move through the decompiled code as quickly and easily as you can in .NET Reflector. When this is selected, the add-in decompiles the given assembly, Once the decompilation has finished, a clone of the Reflector assembly explorer can be used inside Visual Studio. When Reflector generates the source code, it records the location information. You can therefore navigate from the source file to other decompiled source using the 'Go To Definition' context menu item. This then takes you to the definition in another decompiled assembly. .NET Reflector VSPro .NET Reflector VSPro builds on the features in .NET Reflector VS to add the ability to debug any source code you decompile. When you decompile with .NET Reflector VSPro, a matching .pdb is generated, so you can use Visual Studio to debug the source code as if it were part of the project. You can now use all the standard debugging techniques that you are used to in the Visual Studio debugger, and step through decompiled code as if it were your own. Again, you can select assemblies for decompilation. They are then decompiled. And then you can debug as if they were one of your own source code files. The future of .NET Reflector As I have mentioned throughout this post, most of the new features in version 7 are exploratory steps and we will be watching feedback closely. Although we don't want to speculate now about any other new features or bugs that will or won't be fixed in the next few versions of .NET Reflector, Bart has mentioned in a previous post that there are lots of improvements we intend to make. We plan to do this with great care and without taking anything away from the simplicity of the core product. User experience is something that we pride ourselves on at Red Gate, and it is clear that Reflector is still a long way off our usual standards. We plan for the next few versions of Reflector to be worked on by some of our top usability specialists who have been involved with our other market-leading products such as the ANTS Profilers and SQL Compare. I re-iterate the need for the really great simple mode in .NET Reflector to remain intact regardless of any other improvements we are planning to make. I really hope that you enjoy using some of the new features in version 7 and that Reflector continues to be your favourite .NET development tool for a long time to come.

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  • WPF: Timers

    - by Ilya Verbitskiy
    I believe, once your WPF application will need to execute something periodically, and today I would like to discuss how to do that. There are two possible solutions. You can use classical System.Threading.Timer class or System.Windows.Threading.DispatcherTimer class, which is the part of WPF. I have created an application to show you how to use the API.     Let’s take a look how you can implement timer using System.Threading.Timer class. First of all, it has to be initialized.   1: private Timer timer; 2:   3: public MainWindow() 4: { 5: // Form initialization code 6: 7: timer = new Timer(OnTimer, null, Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan); 8: }   Timer’s constructor accepts four parameters. The first one is the callback method which is executed when timer ticks. I will show it to you soon. The second parameter is a state which is passed to the callback. It is null because there is nothing to pass this time. The third parameter is the amount of time to delay before the callback parameter invokes its methods. I use System.Threading.Timeout helper class to represent infinite timeout which simply means the timer is not going to start at the moment. And the final fourth parameter represents the time interval between invocations of the methods referenced by callback. Infinite timeout timespan means the callback method will be executed just once. Well, the timer has been created. Let’s take a look how you can start the timer.   1: private void StartTimer(object sender, RoutedEventArgs e) 2: { 3: timer.Change(TimeSpan.Zero, new TimeSpan(0, 0, 1)); 4:   5: // Disable the start buttons and enable the reset button. 6: }   The timer is started by calling its Change method. It accepts two arguments: the amount of time to delay before the invoking the callback method and the time interval between invocations of the callback. TimeSpan.Zero means we start the timer immediately and TimeSpan(0, 0, 1) tells the timer to tick every second. There is one method hasn’t been shown yet. This is the callback method OnTimer which does a simple task: it shows current time in the center of the screen. Unfortunately you cannot simple write something like this:   1: clock.Content = DateTime.Now.ToString("hh:mm:ss");   The reason is Timer runs callback method on a separate thread, and it is not possible to access GUI controls from a non-GUI thread. You can avoid the problem using System.Windows.Threading.Dispatcher class.   1: private void OnTimer(object state) 2: { 3: Dispatcher.Invoke(() => ShowTime()); 4: } 5:   6: private void ShowTime() 7: { 8: clock.Content = DateTime.Now.ToString("hh:mm:ss"); 9: }   You can build similar application using System.Windows.Threading.DispatcherTimer class. The class represents a timer which is integrated into the Dispatcher queue. It means that your callback method is executed on GUI thread and you can write a code which updates your GUI components directly.   1: private DispatcherTimer dispatcherTimer; 2:   3: public MainWindow() 4: { 5: // Form initialization code 6:   7: dispatcherTimer = new DispatcherTimer { Interval = new TimeSpan(0, 0, 1) }; 8: dispatcherTimer.Tick += OnDispatcherTimer; 9: } Dispatcher timer has nicer and cleaner API. All you need is to specify tick interval and Tick event handler. The you just call Start method to start the timer.   private void StartDispatcher(object sender, RoutedEventArgs e) { dispatcherTimer.Start(); // Disable the start buttons and enable the reset button. } And, since the Tick event handler is executed on GUI thread, the code which sets the actual time is straightforward.   1: private void OnDispatcherTimer(object sender, EventArgs e) 2: { 3: ShowTime(); 4: } We’re almost done. Let’s take a look how to stop the timers. It is easy with the Dispatcher Timer.   1: dispatcherTimer.Stop(); And slightly more complicated with the Timer. You should use Change method again.   1: timer.Change(Timeout.InfiniteTimeSpan, Timeout.InfiniteTimeSpan); What is the best way to add timer into an application? The Dispatcher Timer has simple interface, but its advantages are disadvantages at the same time. You should not use it if your Tick event handler executes time-consuming operations. It freezes your window which it is executing the event handler method. You should think about using System.Threading.Timer in this case. The code is available on GitHub.

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  • Defensive Programming Techniques.

    - by Pemdas
    I was attempting to identify an element of software engineering that I think is overlooked, not emphasized or not taught in typical undergraduate course work for CS or SE. What I came up is the concept of defensive programing. I would like to hear the communities options on defensive program and/or specific techniques that you use on a regular basis. Also, I would to know if there are any language specific techniques.

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  • ASP.NET MVC 3 Hosting :: How to Upgrade ASP.NET MVC 2 Project to ASP.NET MVC 3

    - by mbridge
    ASP.NET MVC 3 can be installed side by side with ASP.NET MVC 2 on the same computer, which gives you flexibility in choosing when to upgrade an ASP.NET MVC 2 application to ASP.NET MVC 3. The simplest way to upgrade is to create a new ASP.NET MVC 3 project and copy all the views, controllers, code, and content files from the existing MVC 2 project to the new project and then to update the assembly references in the new project to match the old project. If you have made changes to the Web.config file in the MVC 2 project, you must also merge those changes with the Web.config file in the MVC 3 project. To manually upgrade an existing ASP.NET MVC 2 application to version 3, do the following: 1. In both Web.config files in the MVC 3 project, globally search and replace the MVC version. Find the following: System.Web.Mvc, Version=2.0.0.0 Replace it with the following System.Web.Mvc, Version=3.0.0.0 There are three changes in the root Web.config and four in the Views\Web.config file. 2. In Solution Explorer, delete the reference to System.Web.Mvc (which points to the version 2 DLL). Then add a reference to System.Web.Mvc (v3.0.0.0). 3. In Solution Explorer, right-click the project name and then select Unload Project. Then right-click again and select Edit ProjectName.csproj. 4. Locate the ProjectTypeGuids element and replace {F85E285D-A4E0-4152-9332-AB1D724D3325} with {E53F8FEA-EAE0-44A6-8774-FFD645390401}. 5. Save the changes and then right-click the project and select Reload Project. 6. If the project references any third-party libraries that are compiled using ASP.NET MVC 2, add the following highlighted bindingRedirect element to the Web.config file in the application root under the configuration section: <runtime>   <assemblyBinding >     <dependentAssembly>       <assemblyIdentity name="System.Web.Mvc"           publicKeyToken="31bf3856ad364e35"/>       <bindingRedirect oldVersion="2.0.0.0" newVersion="3.0.0.0"/>     </dependentAssembly>   </assemblyBinding> </runtime> Another ASP.NET MVC 3 article: - Rolling with Razor in MVC v3 Preview - Deploying ASP.NET MVC 3 web application to server where ASP.NET MVC 3 is not installed - RenderAction with ASP.NET MVC 3 Sessionless Controllers

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  • Dynamic Filtering

    - by Ricardo Peres
    Continuing my previous posts on dynamic LINQ, now it's time for dynamic filtering. For now, I'll focus on string matching. There are three standard operators for string matching, which both NHibernate, Entity Framework and LINQ to SQL recognize: Equals Contains StartsWith EndsWith So, if we want to apply filtering by one of these operators on a string property, we can use this code: public enum MatchType { StartsWith = 0, EndsWith = 1, Contains = 2, Equals = 3 } public static List Filter(IEnumerable enumerable, String propertyName, String filter, MatchType matchType) { return (Filter(enumerable, typeof(T), propertyName, filter, matchType) as List); } public static IList Filter(IEnumerable enumerable, Type elementType, String propertyName, String filter, MatchType matchType) { MethodInfo asQueryableMethod = typeof(Queryable).GetMethods(BindingFlags.Static | BindingFlags.Public).Where(m = (m.Name == "AsQueryable") && (m.ContainsGenericParameters == false)).Single(); IQueryable query = (enumerable is IQueryable) ? (enumerable as IQueryable) : asQueryableMethod.Invoke(null, new Object [] { enumerable }) as IQueryable; MethodInfo whereMethod = typeof(Queryable).GetMethods(BindingFlags.Public | BindingFlags.Static).Where(m = m.Name == "Where").ToArray() [ 0 ].MakeGenericMethod(elementType); MethodInfo matchMethod = typeof(String).GetMethod ( (matchType == MatchType.StartsWith) ? "StartsWith" : (matchType == MatchType.EndsWith) ? "EndsWith" : (matchType == MatchType.Contains) ? "Contains" : "Equals", new Type [] { typeof(String) } ); PropertyInfo displayProperty = elementType.GetProperty(propertyName, BindingFlags.Public | BindingFlags.Instance); MemberExpression member = Expression.MakeMemberAccess(Expression.Parameter(elementType, "n"), displayProperty); MethodCallExpression call = Expression.Call(member, matchMethod, Expression.Constant(filter)); LambdaExpression where = Expression.Lambda(call, member.Expression as ParameterExpression); query = whereMethod.Invoke(null, new Object [] { query, where }) as IQueryable; MethodInfo toListMethod = typeof(Enumerable).GetMethod("ToList", BindingFlags.Static | BindingFlags.Public).MakeGenericMethod(elementType); IList list = toListMethod.Invoke(null, new Object [] { query }) as IList; return (list); } var list = new [] { new { A = "aa" }, new { A = "aabb" }, new { A = "ccaa" }, new { A = "ddaadd" } }; var contains = Filter(list, "A", "aa", MatchType.Contains); var endsWith = Filter(list, "A", "aa", MatchType.EndsWith); var startsWith = Filter(list, "A", "aa", MatchType.StartsWith); var equals = Filter(list, "A", "aa", MatchType.Equals); Perhaps I'll write some more posts on this subject in the near future. SyntaxHighlighter.config.clipboardSwf = 'http://alexgorbatchev.com/pub/sh/2.0.320/scripts/clipboard.swf'; SyntaxHighlighter.brushes.CSharp.aliases = ['c#', 'c-sharp', 'csharp']; SyntaxHighlighter.all();

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  • XAML2CPP 1.0.1.0

    - by Valter Minute
    I upgraded XAML2CPP to fix some bugs and support some new features that will be used in my next tutorial step (that I hope to publish very soon!). Bug fixed: the listbox selection changed event was generated with an incorrect prototype events generated by the XAML tree root element (UserControl) were not handled. New features: XAML2CPP generates panels (dynamically generated XAML subtrees that may be added to a page) and user controls (those will be the object of my next post, stay tuned!). XAML2CPPXRValue class has been added to XAML2CPPbase.h. This class will allow single-line declaration of XRValue objects (I’m lazy!) and destroys automatically objects and string XRValues when the object itself is destroyed. You can download the latest XAML2CPP release here: http://cid-9b7b0aefe3514dc5.skydrive.live.com/self.aspx/.Public/XAML2CPP.zip

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  • DB DOC Enhancements for Oracle SQL Developer v4

    - by thatjeffsmith
    One of our more popular features is ‘DB Doc.’ It’s like JAVADOC for the database. Pick a connection, right-click, and go. It will generate an HTML documentation set for that schema. For version 4, we’ve introduced a few enhancements based on user requests. That’s right, you asked, and we listened. Added support for Package Bodies Added parallelization option for larger doc sets Enhanced the HTML formatting a bit Select Your Object Types and Generation Options We’ve changed the default selection of object types to be included and added support for package bodies There’s also an option to auto-open the documentation set after it’s been generated. And the HTML As Requested

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  • Drawing graphics in Java game

    - by wolf
    I am quite new to game development, so here is a question (maybe a stupid one): In my sidescroller i have a bunch of different graphics objects that i need to draw (player, background tiles, creatures, projectiles etc). Most tutorials i've read so far show that each object has its own draw method, which is then called from some other method. What if I had one method that does all the drawing? Lets say i keep all my objects in an array or queue (or multiple arrays) and then go through each of them, get an image and draw it. So basically would it be better (and why) to have each object have its own draw method or one method that does all the drawing? Or does it matter at all? I feel like the second option is more comfortable, because then all the stuff to do with drawing would be in one place...

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  • conventions for friend methods in Perl

    - by xenoterracide
    Perl doesn't support a friend relationship between objects, nor does it support private or protected methods. What is usually done for private methods is to prefix the name with an underscore. I occasionally have methods that I think of as friend methods. Meaning that I expect them to be used by a specific object, or an object with a specific responsibility, but I'm not sure if I should make that method public (meaning foo ) or private ( _foo ) or if there's a better convention? is there a convention for friend methods?

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  • Case Class naming convention

    - by KChaloux
    In my recent adventures in Scala, I've found case classes to be a really nice alternative to enums when I need to include a bit of logic or several values with them. I often find myself writing structures that look like this, however: object Foo{ case class Foo(name: String, value: Int, other: Double) val BAR = Foo("bar", 1, 1.0) val BAZ = Foo("baz", 2, 1.5) val QUUX = Foo("quux", 3, 1.75) } I'm primarily worried here about the naming of the object and the case class. Since they're the same thing, I end up with Foo.Foo to get to the inner class. Would it be wise to name the case class something along the lines of FooCase instead? I'm not sure if the potential ambiguity might mess with the type system if I have to do anything with subtypes or inheritance.

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  • How to impale and stack targets correctly according to the collider and its coordinate?

    - by David Dimalanta
    I'm making another simple game, a catch game, where a spawning target game object must be captured using a skewer to impale it. Here how: At the start, the falling object (in red) will fall in a vertical direction (in blue) When aimed properly, the target will fall down along the line of the skewer. (in blue) Then, another target is spawned and will fall vertically. (in red) When aimed successfully again in a streak, the second target will fall along the skewer and stacked. Same process over and over when another target is spawned. However, when I test run it on the scene tab in Unity, when impaled several targets, instead of a smooth flow and stacking it ended up overlaying it instead of stacking it up like a pancake. Here's what it look like: As I noticed when reaching the half-way of my progress, I tried to figure out how to deal with collider bodies without sticking each other so that it will actually stack like in the example of the image at no. 3. Here's the script code I added in the target game object: using UnityEngine; using System.Collections; public class ImpaleStateTest : MonoBehaviour { public GameObject target; public GameObject skewer; public bool drag = false; private float stack; private float impaleCount; void Start () { stack = 0; impaleCount = 0; } void Update () { if(drag) { target.transform.position = new Vector3 (DragTest.dir.transform.position.x, DragTest.dir.transform.position.y - 0.35f, 0); target.transform.rotation = DragTest.degrees; target.rigidbody2D.fixedAngle = true; target.rigidbody2D.isKinematic = true; target.rigidbody2D.gravityScale = 0; if(Input.GetMouseButton(0)) { Debug.Log ("Skewer: " + DragTest.dir.transform.position.x); Debug.Log ("Target: " + target.transform.position.x); } } } void OnTriggerEnter2D(Collider2D collider) { impaleCount++; Debug.Log ("Impaled " + impaleCount + " time(s)!"); drag = true; audio.Play (); } } Aside from that, I'm not sure if it's right but, the only way to stick the impaled targets while dragging the skewer left or right is to get the X coordinates from the skewer only. Is there something else to recommend it in order to improve this behavior as realistic as possible? Please help.

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  • Using heavyweight ORM implementation for light based games

    - by Holland
    I'm just about to engulf myself in an MVC-based/Component architecture in C#, using MySQL's connector/Net for the data storage, and probably some NHibernate/FluentNHibernate Object-relational-mapping to map out the data structure. The goal is to build a scalable 2D RPG. Then I think about it...and I can't help but think this seems a little "heavy weight" for a 2D RPG, especially one which, while I plan to incorporate a lot of functionality and entertaining gameplay, may be ported to something like Windows Phone or Android in the future. Yet, on the other hand even a 2-Dimensional RPG can become very complicated, and therefore must incorporate a lot of functionality. While this can be accomplished with text/XML/JSON for data storage, is there a better way? Is something such as Object-Relational-Mapping useful in such an application? So, what do you think? Would you say that there is a place for such technologies? I don't know what to think...

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  • Do immutable objects and DDD go together?

    - by SnOrfus
    Consider a system that uses DDD (as well: any system that uses an ORM). The point of any system realistically, in nearly every use case, will be to manipulate those domain objects. Otherwise there's no real effect or purpose. Modifying an immutable object will cause it to generate a new record after the object is persisted which creates massive bloat in the datasource (unless you delete previous records after modifications). I can see the benefit of using immutable objects, but in this sense, I can't ever see a useful case for using immutable objects. Is this wrong?

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  • Get Application Title from Windows Phone

    - by psheriff
    In a Windows Phone application that I am currently developing I needed to be able to retrieve the Application Title of the phone application. You can set the Deployment Title in the Properties of your Windows Phone Application, however getting to this value programmatically can be a little tricky. This article assumes that you have Visual Studio 2010 and the Windows Phone tools installed along with it. The Windows Phone tools must be downloaded separately and installed with Visual Studio2010. You may also download the free Visual Studio2010 Express for Windows Phone developer environment. The WMAppManifest.xml File First off you need to understand that when you set the Deployment Title in the Properties windows of your Windows Phone application, this title actually gets stored into an XML file located under the \Properties folder of your application. This XML file is named WMAppManifest.xml. A portion of this file is shown in the following listing. <?xml version="1.0" encoding="utf-8"?><Deployment  http://schemas.microsoft.com/windowsphone/2009/deployment"http://schemas.microsoft.com/windowsphone/2009/deployment"  AppPlatformVersion="7.0">  <App xmlns=""       ProductID="{71d20842-9acc-4f2f-b0e0-8ef79842ea53}"       Title="Mobile Time Track"       RuntimeType="Silverlight"       Version="1.0.0.0"       Genre="apps.normal"       Author="PDSA, Inc."       Description="Mobile Time Track"       Publisher="PDSA, Inc."> ... ...  </App></Deployment> Notice the “Title” attribute in the <App> element in the above XML document. This is the value that gets set when you modify the Deployment Title in your Properties Window of your Phone project. The only value you can set from the Properties Window is the Title. All of the other attributes you see here must be set by going into the XML file and modifying them directly. Note that this information duplicates some of the information that you can also set from the Assembly Information… button in the Properties Window. Why Microsoft did not just use that information, I don’t know. Reading Attributes from WMAppManifest I searched all over the namespaces and classes within the Windows Phone DLLs and could not find a way to read the attributes within the <App> element. Thus, I had to resort to good old fashioned XML processing. First off I created a WinPhoneCommon class and added two static methods as shown in the snippet below: public class WinPhoneCommon{  /// <summary>  /// Returns the Application Title   /// from the WMAppManifest.xml file  /// </summary>  /// <returns>The application title</returns>  public static string GetApplicationTitle()  {    return GetWinPhoneAttribute("Title");  }   /// <summary>  /// Returns the Application Description   /// from the WMAppManifest.xml file  /// </summary>  /// <returns>The application description</returns>  public static string GetApplicationDescription()  {    return GetWinPhoneAttribute("Description");  }   ... GetWinPhoneAttribute method here ...} In your Windows Phone application you can now simply call WinPhoneCommon.GetApplicationTitle() or WinPhone.GetApplicationDescription() to retrieve the Title or Description properties from the WMAppManifest.xml file respectively. You notice that each of these methods makes a call to the GetWinPhoneAttribute method. This method is shown in the following code snippet: /// <summary>/// Gets an attribute from the Windows Phone WMAppManifest.xml file/// To use this method, add a reference to the System.Xml.Linq DLL/// </summary>/// <param name="attributeName">The attribute to read</param>/// <returns>The Attribute's Value</returns>private static string GetWinPhoneAttribute(string attributeName){  string ret = string.Empty;   try  {    XElement xe = XElement.Load("WMAppManifest.xml");    var attr = (from manifest in xe.Descendants("App")                select manifest).SingleOrDefault();    if (attr != null)      ret = attr.Attribute(attributeName).Value;  }  catch  {    // Ignore errors in case this method is called    // from design time in VS.NET  }   return ret;} I love using the new LINQ to XML classes contained in the System.Xml.Linq.dll. When I did a Bing search the only samples I found for reading attribute information from WMAppManifest.xml used either an XmlReader or XmlReaderSettings objects. These are fine and work, but involve a little extra code. Instead of using these, I added a reference to the System.Xml.Linq.dll, then added two using statements to the top of the WinPhoneCommon class: using System.Linq;using System.Xml.Linq; Now, with just a few lines of LINQ to XML code you can read to the App element and extract the appropriate attribute that you pass into the GetWinPhoneAttribute method. Notice that I added a little bit of exception handling code in this method. I ignore the exception in case you call this method in the Loaded event of a user control. In design-time you cannot access the WMAppManifest file and thus an exception would be thrown. Summary In this article you learned how to retrieve the attributes from the WMAppManifest.xml file. I use this technique to grab information that I would otherwise have to hard-code in my application. Getting the Title or Description for your Windows Phone application is easy with just a little bit of LINQ to XML code. NOTE: You can download the complete sample code at my website. http://www.pdsa.com/downloads. Choose Tips & Tricks, then "Get Application Title from Windows Phone" from the drop-down. Good Luck with your Coding,Paul Sheriff ** SPECIAL OFFER FOR MY BLOG READERS **Visit http://www.pdsa.com/Event/Blog for a free video on Silverlight entitled Silverlight XAML for the Complete Novice - Part 1.  

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  • Abstract class + Inheritance vs Interface

    - by RealityDysfunction
    Hello fellow programmers, I am reading a book on C# and the author is comparing Abstract classes and Interfaces. He claims that if you have the following "abstract class:" abstract class CloneableType { public abstract object Clone(); } Then you cannot do this: public class MiniVan : Car, CloneableType {} This, I understand. However he claims that because of this inability to do multiple inheritance that you should use an interface for CloneableType, like so: public interface ICloneable { object Clone(); } My question is, isn't this somewhat misleading, because you can create an abstract class which is "above" class Car with the method Clone, then have Car inherit that class and then Minivan will inherit Car with all these methods, CloneAble class - Car class - Minivan Class. What do you think? Thanks.

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  • Subterranean IL: Exception handler semantics

    - by Simon Cooper
    In my blog posts on fault and filter exception handlers, I said that the same behaviour could be replicated using normal catch blocks. Well, that isn't entirely true... Changing the handler semantics Consider the following: .try { .try { .try { newobj instance void [mscorlib]System.Exception::.ctor() // IL for: // e.Data.Add("DictKey", true) throw } fault { ldstr "1: Fault handler" call void [mscorlib]System.Console::WriteLine(string) endfault } } filter { ldstr "2a: Filter logic" call void [mscorlib]System.Console::WriteLine(string) // IL for: // (bool)((Exception)e).Data["DictKey"] endfilter }{ ldstr "2b: Filter handler" call void [mscorlib]System.Console::WriteLine(string) leave.s Return } } catch object { ldstr "3: Catch handler" call void [mscorlib]System.Console::WriteLine(string) leave.s Return } Return: // rest of method If the filter handler is engaged (true is inserted into the exception dictionary) then the filter handler gets engaged, and the following gets printed to the console: 2a: Filter logic 1: Fault handler 2b: Filter handler and if the filter handler isn't engaged, then the following is printed: 2a:Filter logic 1: Fault handler 3: Catch handler Filter handler execution The filter handler is executed first. Hmm, ok. Well, what happens if we replaced the fault block with the C# equivalent (with the exception dictionary value set to false)? .try { // throw exception } catch object { ldstr "1: Fault handler" call void [mscorlib]System.Console::WriteLine(string) rethrow } we get this: 1: Fault handler 2a: Filter logic 3: Catch handler The fault handler is executed first, instead of the filter block. Eh? This change in behaviour is due to the way the CLR searches for exception handlers. When an exception is thrown, the CLR stops execution of the thread, and searches up the stack for an exception handler that can handle the exception and stop it propagating further - catch or filter handlers. It checks the type clause of catch clauses, and executes the code in filter blocks to see if the filter can handle the exception. When the CLR finds a valid handler, it saves the handler's location, then goes back to where the exception was thrown and executes fault and finally blocks between there and the handler location, discarding stack frames in the process, until it reaches the handler. So? By replacing a fault with a catch, we have changed the semantics of when the filter code is executed; by using a rethrow instruction, we've split up the exception handler search into two - one search to find the first catch, then a second when the rethrow instruction is encountered. This is only really obvious when mixing C# exception handlers with fault or filter handlers, so this doesn't affect code written only in C#. However it could cause some subtle and hard-to-debug effects with object initialization and ordering when using and calling code written in a language that can compile fault and filter handlers.

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