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  • "Imprinting" as a language feature?

    - by MKO
    Idea I had this idea for a language feature that I think would be useful, does anyone know of a language that implements something like this? The idea is that besides inheritance a class can also use something called "imprinting" (for lack of better term). A class can imprint one or several (non-abstract) classes. When a class imprints another class it gets all it's properties and all it's methods. It's like the class storing an instance of the imprinted class and redirecting it's methods/properties to it. A class that imprints another class therefore by definition also implements all it's interfaces and it's abstract class. So what's the point? Well, inheritance and polymorphism is hard to get right. Often composition gives far more flexibility. Multiple inheritance offers a slew of different problems without much benefits (IMO). I often write adapter classes (in C#) by implementing some interface and passing along the actual methods/properties to an encapsulated object. The downside to that approach is that if the interface changes the class breaks. You also you have to put in a lot of code that does nothing but pass things along to the encapsulated object. A classic example is that you have some class that implements IEnumerable or IList and contains an internal class it uses. With this technique things would be much easier Example (c#) [imprint List<Person> as peopleList] public class People : PersonBase { public void SomeMethod() { DoSomething(this.Count); //Count is from List } } //Now People can be treated as an List<Person> People people = new People(); foreach(Person person in people) { ... } peopleList is an alias/variablename (of your choice)used internally to alias the instance but can be skipped if not needed. One thing that's useful is to override an imprinted method, that could be achieved with the ordinary override syntax public override void Add(Person person) { DoSomething(); personList.Add(person); } note that the above is functional equivalent (and could be rewritten by the compiler) to: public class People : PersonBase , IList<Person> { private List<Person> personList = new List<Person>(); public override void Add(object obj) { this.personList.Add(obj) } public override int IndexOf(object obj) { return personList.IndexOf(obj) } //etc etc for each signature in the interface } only if IList changes your class will break. IList won't change but an interface that you, someone in your team, or a thirdparty has designed might just change. Also this saves you writing a whole lot of code for some interfaces/abstract classes. Caveats There's a couple of gotchas. First we, syntax must be added to call the imprinted classes's constructors from the imprinting class constructor. Also, what happends if a class imprints two classes which have the same method? In that case the compiler would detect it and force the class to define an override of that method (where you could chose if you wanted to call either imprinted class or both) So what do you think, would it be useful, any caveats? It seems it would be pretty straightforward to implement something like that in the C# language but I might be missing something :) Sidenote - Why is this different from multiple inheritance Ok, so some people have asked about this. Why is this different from multiple inheritance and why not multiple inheritance. In C# methods are either virtual or not. Say that we have ClassB who inherits from ClassA. ClassA has the methods MethodA and MethodB. ClassB overrides MethodA but not MethodB. Now say that MethodB has a call to MethodA. if MethodA is virtual it will call the implementation that ClassB has, if not it will use the base class, ClassA's MethodA and you'll end up wondering why your class doesn't work as it should. By the terminology sofar you might already confused. So what happens if ClassB inherits both from ClassA and another ClassC. I bet both programmers and compilers will be scratching their heads. The benefit of this approach IMO is that the imprinting classes are totally encapsulated and need not be designed with multiple inheritance in mind. You can basically imprint anything.

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  • Extending Expression Blend 4 &amp; Blend for Visual Studio 2012

    - by Chris Skardon
    Just getting this off the bat, I presume this will also work for Blend 5, but I can’t confirm it… Anyhews, I imagine you’re here because you want to know how to create an addin for Blend, so let’s jump right in there! First, and foremost, we’re going to need to ensure our development environment has the right setup, so the checklist: Visual Studio 2012 Blend for Visual Studio 2012 OK, let’s create a new project (class library, .NET 4.5): Hello.Extension The ‘.Extension’ bit is very very important. The addin will not work unless it is named in this way. You can put whatever you want at the front, but it has to have the extension bit. OK, so now we have a solution with one project. To this project we need to add references to the following things: Microsoft.Expression.Extensibility (from c:\program files\Microsoft Visual Studio 11.0\Blend\   -- x86 folder if you are on an x64 windows install) Microsoft.Expression.Framework (same location as above) PresentationCore PresentationFramework WindowsBase System.ComponentModel.Composition Got them? ACE. Let’s now add a project to contain our control, so, create a new WPF Application project, cunningly named something like ‘Hello.Control’… (I’m creating a WPF application here, because I’m too lazy to dig up the correct references, and this will add all the ones I need ) Once that is created, delete the App.xaml and MainWindow.xaml files, we won’t be needing them. You will also need to change the properties of the project itself, so it is only a class library. Once that is done, let’s add a new UserControl, which will be this: <UserControl x:Class="Hello.Control.HelloControl" xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" xmlns:d="http://schemas.microsoft.com/expression/blend/2008" mc:Ignorable="d" d:DesignHeight="300" d:DesignWidth="300"> <Grid> <TextBlock Text="HELLO!!!"/> </Grid> </UserControl> Impressive eh? Now, let’s reference the WPF project from the Extension library. All that’s left now is to code up our extension… So, add a class to the Extension project (name wise doesn’t matter), and make it implement the IPackage interface from the Microsoft.Expression.Extensibility library: public class HelloExtension : IPackage { /**/ } We’ll implement the two methods we need to: public class HelloExtension : IPackage { public void Load(IServices services) { } public void Unload() { } } We’re only really concerned about the Load method in this case, as let’s face it, the extension we have doesn’t need to do a lot to bog off. The interesting thing about the Load method is that it receives an IServices instance. This allows us to get access to all the services that Expression provides, in this case we’re interested in one in particular, the ‘IWindowService’ So, let’s get that bad boy… private IWindowService _windowService; public void Load(IServices services) { _windowService = services.GetService<IWindowService>(); } Nailed it… But why? The WindowService allows us to register our UserControl with Blend, which in turn allows people to activate and see it, which is a big plus point. So, let’s do that… We’ll create an ‘Initialize’ method to create our new control, and add it to the WindowService: private HelloControl _helloControl; public void Initialize() { _helloControl = new HelloControl(); if (_windowService.PaletteRegistry["HelloPanel"] == null) _windowService.RegisterPalette("HelloPanel", _helloControl, "Hello Window"); } First we check that we’re not already registered, and if we’re not we register, the first argument is the identifier used by the service to, well, identify your extension. The second argument is the actual control, the third argument is the name that people will see in the ‘Windows’ menu of Blend itself (so important note here – don’t put anything embarrassing or (need I say it?) sweary…) There are only two things to do now - Call ‘Initialize()’ from our Load method, and Export the class This is easy money – add [Export(typeof(IPackage))] to the top of our class… The full code will (should) look like this: [Export(typeof (IPackage))] public class HelloExtension : IPackage { private HelloControl _helloControl; private IWindowService _windowService; public void Load(IServices services) { _windowService = services.GetService<IWindowService>(); Initialize(); } public void Unload() { } public void Initialize() { _helloControl = new HelloControl(); if (_windowService.PaletteRegistry["HelloControl"] == null) _windowService.RegisterPalette("HelloControl", _helloControl, "Hello Window"); } } If you build this and copy it to your ‘Extensions’ folder in Blend (c:\program files\microsoft visual studio 11.0\blend\) and start Blend, you should see ‘Hello Window’ listed in the Window menu: That as they say is it!

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  • Storing non-content data in Orchard

    - by Bertrand Le Roy
    A CMS like Orchard is, by definition, designed to store content. What differentiates content from other kinds of data is rather subtle. The way I would describe it is by saying that if you would put each instance of a kind of data on its own web page, if it would make sense to add comments to it, or tags, or ratings, then it is content and you can store it in Orchard using all the convenient composition options that it offers. Otherwise, it probably isn't and you can store it using somewhat simpler means that I will now describe. In one of the modules I wrote, Vandelay.ThemePicker, there is some configuration data for the module. That data is not content by the definition I gave above. Let's look at how this data is stored and queried. The configuration data in question is a set of records, each of which has a number of properties: public class SettingsRecord { public virtual int Id { get; set;} public virtual string RuleType { get; set; } public virtual string Name { get; set; } public virtual string Criterion { get; set; } public virtual string Theme { get; set; } public virtual int Priority { get; set; } public virtual string Zone { get; set; } public virtual string Position { get; set; } } .csharpcode, .csharpcode pre { font-size: small; color: black; font-family: consolas, "Courier New", courier, monospace; background-color: #ffffff; /*white-space: pre;*/ } .csharpcode pre { margin: 0em; } .csharpcode .rem { color: #008000; } .csharpcode .kwrd { color: #0000ff; } .csharpcode .str { color: #006080; } .csharpcode .op { color: #0000c0; } .csharpcode .preproc { color: #cc6633; } .csharpcode .asp { background-color: #ffff00; } .csharpcode .html { color: #800000; } .csharpcode .attr { color: #ff0000; } .csharpcode .alt { background-color: #f4f4f4; width: 100%; margin: 0em; } .csharpcode .lnum { color: #606060; } Each property has to be virtual for nHibernate to handle it (it creates derived classed that are instrumented in all kinds of ways). We also have an Id property. The way these records will be stored in the database is described from a migration: public int Create() { SchemaBuilder.CreateTable("SettingsRecord", table => table .Column<int>("Id", column => column.PrimaryKey().Identity()) .Column<string>("RuleType", column => column.NotNull().WithDefault("")) .Column<string>("Name", column => column.NotNull().WithDefault("")) .Column<string>("Criterion", column => column.NotNull().WithDefault("")) .Column<string>("Theme", column => column.NotNull().WithDefault("")) .Column<int>("Priority", column => column.NotNull().WithDefault(10)) .Column<string>("Zone", column => column.NotNull().WithDefault("")) .Column<string>("Position", column => column.NotNull().WithDefault("")) ); return 1; } When we enable the feature, the migration will run, which will create the table in the database. Once we've done that, all we have to do in order to use the data is inject an IRepository<SettingsRecord>, which is what I'm doing from the set of helpers I put under the SettingsService class: private readonly IRepository<SettingsRecord> _repository; private readonly ISignals _signals; private readonly ICacheManager _cacheManager; public SettingsService( IRepository<SettingsRecord> repository, ISignals signals, ICacheManager cacheManager) { _repository = repository; _signals = signals; _cacheManager = cacheManager; } The repository has a Table property, which implements IQueryable<SettingsRecord> (enabling all kind of Linq queries) as well as methods such as Delete and Create. Here's for example how I'm getting all the records in the table: _repository.Table.ToList() And here's how I'm deleting a record: _repository.Delete(_repository.Get(r => r.Id == id)); And here's how I'm creating one: _repository.Create(new SettingsRecord { Name = name, RuleType = ruleType, Criterion = criterion, Theme = theme, Priority = priority, Zone = zone, Position = position }); In summary, you create a record class, a migration, and you're in business and can just manipulate the data through the repository that the framework is exposing. You even get ambient transactions from the work context.

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  • The design of a generic data synchronizer, or, an [object] that does [actions] with the aid of [helpers]

    - by acheong87
    I'd like to create a generic data-source "synchronizer," where data-source "types" may include MySQL databases, Google Spreadsheets documents, CSV files, among others. I've been trying to figure out how to structure this in terms of classes and interfaces, keeping in mind (what I've read about) composition vs. inheritance and is-a vs. has-a, but each route I go down seems to violate some principle. For simplicity, assume that all data-sources have a header-row-plus-data-rows format. For example, assume that the first rows of Google Spreadsheets documents and CSV files will have column headers, a.k.a. "fields" (to parallel database fields). Also, eventually, I would like to implement this in PHP, but avoiding language-specific discussion would probably be more productive. Here's an overview of what I've tried. Part 1/4: ISyncable class CMySQL implements ISyncable GetFields() // sql query, pdo statement, whatever AddFields() RemFields() ... _dbh class CGoogleSpreadsheets implements ISyncable GetFields() // zend gdata api AddFields() RemFields() ... _spreadsheetKey _worksheetId class CCsvFile implements ISyncable GetFields() // read from buffer AddFields() RemFields() ... _buffer interface ISyncable GetFields() AddFields($field1, $field2, ...) RemFields($field1, $field2, ...) ... CanAddFields() // maybe the spreadsheet is locked for write, or CanRemFields() // maybe no permission to alter a database table ... AddRow() ModRow() RemRow() ... Open() Close() ... First Question: Does it make sense to use an interface, as above? Part 2/4: CSyncer Next, the thing that does the syncing. class CSyncer __construct(ISyncable $A, ISyncable $B) Push() // sync A to B Pull() // sync B to A Sync() // Push() and Pull() only differ in direction; factor. // Sync()'s job is to make sure that the fields on each side // match, to add fields where appropriate and possible, to // account for different column-orderings, etc., and of // course, to add and remove rows as necessary to sync. ... _A _B Second Question: Does it make sense to define such a class, or am I treading dangerously close to the "Kingdom of Nouns"? Part 3/4: CTranslator? ITranslator? Now, here's where I actually get lost, assuming the above is passable. Sometimes, two ISyncables speak different "dialects." For example, believe it or not, Google Spreadsheets (accessed through the Google Data API "list feed") returns column headers lower-cased and stripped of all spaces and symbols! That is, sys_TIMESTAMP is systimestamp, as far as my code can tell. (Yes, I am aware that the "cell feed" does not strip the name so; however cell-by-cell manipulation is too slow for what I'm doing.) One can imagine other hypothetical examples. Perhaps even the data itself can be in different "dialects." But let's take it as given for now, and not argue this if possible. Third Question: How would you implement "translation"? Note: Taking all this as an exercise, I'm more interested in the "idealized" design, rather than the practical one. (God knows that shipped sailed when I began this project.) Part 4/4: Further Thought Here's my train of thought to demonstrate I've thunk, albeit unfruitfully: First, I thought, primitively, "I'll just modify CMySQL::GetFields() to lower-case and strip field names so they're compatible with Google Spreadsheets." But of course, then my class should really be called, CMySQLForGoogleSpreadsheets, and that can't be right. So, the thing which translates must exist outside of an ISyncable implementor. And surely it can't be right to make each translation a method in CSyncer. If it exists outside of both ISyncable and CSyncer, then what is it? (Is it even an "it"?) Is it an abstract class, i.e. abstract CTranslator? Is it an interface, since a translator only does, not has, i.e. interface ITranslator? Does it even require instantiation? e.g. If it's an ITranslator, then should its translation methods be static? (I learned what "late static binding" meant, today.) And, dear God, whatever it is, how should a CSyncer use it? Does it "have" it? Is it, "it"? Who am I? ...am I, "I"? I've attempted to break up the question into sub-questions, but essentially my question is singular: How does one implement an object A that conceptually "links" (has) two objects b1 and b2 that share a common interface B, where certain pairs of b1 and b2 require a helper, e.g. a translator, to be handled by A? Something tells me that I've overcomplicated this design, or violated a principle much higher up. Thank you all very much for your time and any advice you can provide.

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  • Deep Cloning C++ class that inherits CCNode in Cocos2dx

    - by A Devanney
    I stuck with something in Cocos2dx ... I'm trying to deep clone one of my classes that inherits CCNode. Basically i have.... GameItem* pTemp = new GameItem(*_actualItem); // loops through all the blocks in gameitem and updates their position pTemp->moveDown(); // if in boundary or collision etc... if (_gameBoard->isValidMove(pTemp)) { _actualItem = pTemp; // display the position CCLog("pos (1) --- (X : %d,Y : %d)", _actualItem->getGridX(),_actualItem->getGridY()); } Then doesn't work, because the gameitem inherits CCNode and has the collection of another class that also inherits CCNode. its just creating a shallow copy and when you look at children of the gameitem node in the copy, just point to the original? class GameItem : public CCNode { // maps to the actual grid position of the shape CCPoint* _rawPosition; // tracks the current grid position int _gridX, _gridY; // tracks the change if the item has moved CCPoint _offset; public: //constructors GameItem& operator=(const GameItem& item); GameItem(Shape shape); ... } then in the implementation.... GameItem& GameItem::operator=(const GameItem& item) { _gridX = item.getGridX(); _gridY = item.getGridY(); _offset = item.getOffSet(); _rawPosition = item.getRawPosition(); // how do i copy the node? return *this; } // shape contains an array of position for the game character GameItem::GameItem(Shape shape) { _rawPosition = shape.getShapePositions(); //loop through all blocks in position for (int i = 0; i < 7; i++) { // get the position of the first block in the shape and add to the position of the first block int x = (int) (getRawPosition()[i].x + getGridX()); int y = (int) (getRawPosition()[i].y + getGridY()); //instantiate a block with the position and type Block* block = Block::blockWithFile(x,y,(i+1), shape); // add the block to the this node this->addChild(block); } } And for clarity here is the block class class Block : public CCNode{ private: // using composition over inheritance CCSprite* _sprite; // tracks the current grid position int _gridX, _gridY; // used to store actual image number int _blockNo; public: Block(void); Block(int gridX, int gridY, int blockNo); Block& operator=(const Block& block); // static constructor for the creation of a block static Block* blockWithFile(int gridX, int gridY,int blockNo, Shape shape); ... } The blocks implementation..... Block& Block::operator=(const Block& block) { _sprite = new CCSprite(*block._sprite); _gridX = block._gridX; _gridY = block._gridY; _blockNo = block._blockNo; //again how to clone CCNode? return *this; } Block* Block::blockWithFile(int gridX, int gridY,int blockNo, Shape shape) { Block* block = new Block(); if (block && block->initBlockWithFile(gridX, gridY,blockNo, shape)) { block->autorelease(); return block; } CC_SAFE_DELETE(block); return NULL; } bool Block::initBlockWithFile(int gridX, int gridY,int blockNo, Shape shape) { setGridX(gridX); setGridY(gridY); setBlockNo(blockNo); const char* characterImg = helperFunctions::Format(shape.getFileName(),blockNo); // add to the spritesheet CCTexture2D* gameArtTexture = CCTextureCache::sharedTextureCache()->addImage("Character.pvr.ccz"); CCSpriteBatchNode::createWithTexture(gameArtTexture); // block settings _sprite = CCSprite::createWithSpriteFrameName(characterImg); // set the position of the block and add it to the layer this->setPosition(CONVERTGRIDTOACTUALPOS_X_Y(gridX,gridY)); this->addChild(_sprite); return true; } Any ideas are welcome at this point!! thanks

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  • WSIT, Maven, and wsimport -- Can They Work Together?

    - by rtperson
    Hi all, I'm working on a small-ish multi-module project in Maven. We've separated the UI from the database layer using Web Services, and thanks to the jaxws-maven-plugin, the creation of the WSDL and WS client are more or less handled for us. (The plugin is essentially a wrapper around wsgen and wsimport.) So far so good. The problem comes when I try to layer WSIT security into the picture. NetBeans allows me to generate the security metadata easily, but wsimport seems completely incapable of dealing with anything beyond a Basic-auth level of security. Here's our current, insecure way of calling wsimport during a Maven build: <plugin> <groupId>org.codehaus.mojo</groupId> <artifactId>jaxws-maven-plugin</artifactId> <version>1.10</version> <executions> <execution> <goals> <goal>wsimport</goal> </goals> <configuration> <wsdlUrls> <wsdlUrl>${basedir}/../WebService/target/jaxws/wsgen/wsdl/WebService.wsdl</wsdlUrl> </wsdlUrls> <packageName>com.yourcompany.appname.ws.client</packageName> <sourceDestDir>${basedir}/src/main/java</sourceDestDir> <destDir>${basedir}/target/jaxws</destDir> </configuration> </execution> </executions> </plugin> I have tried playing around with xauthFile, xadditionalHeaders, passing javax.xml.ws.security.auth.username and password through args. I have also tried using wsimport from the command line to point to the Tomcat-generated WSDL, which has the additional security info. Nothing, however, seems to change the composition of the wsimport-generated files at all. So I guess my question here is, to get a WSIT-compliant client, am I stuck abandoning Maven and the jaxws plugin altogether? Is there a way to get a WSIT client to auto-generate? Or will I need to generate the client by hand? Let me know if you need any additional info beyond what I've written here. I'm deploying to Tomcat, although that doesn't seem to be an issue, as Maven seems happy to pull Metro into the deployed WAR file. Thanks in advance!

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  • How can arguments to variadic functions be passed by reference in PHP?

    - by outis
    Assuming it's possible, how would one pass arguments by reference to a variadic function without generating a warning in PHP? We can no longer use the '&' operator in a function call, otherwise I'd accept that (even though it would be error prone, should a coder forget it). What inspired this is are old MySQLi wrapper classes that I unearthed (these days, I'd just use PDO). The only difference between the wrappers and the MySQLi classes is the wrappers throw exceptions rather than returning FALSE. class DBException extends RuntimeException {} ... class MySQLi_throwing extends mysqli { ... function prepare($query) { $stmt = parent::prepare($query); if (!$stmt) { throw new DBException($this->error, $this->errno); } return new MySQLi_stmt_throwing($this, $query, $stmt); } } // I don't remember why I switched from extension to composition, but // it shouldn't matter for this question. class MySQLi_stmt_throwing /* extends MySQLi_stmt */ { protected $_link, $_query, $_delegate; public function __construct($link, $query, $prepared) { //parent::__construct($link, $query); $this->_link = $link; $this->_query = $query; $this->_delegate = $prepared; } function bind_param($name, &$var) { return $this->_delegate->bind_param($name, $var); } function __call($name, $args) { //$rslt = call_user_func_array(array($this, 'parent::' . $name), $args); $rslt = call_user_func_array(array($this->_delegate, $name), $args); if (False === $rslt) { throw new DBException($this->_link->error, $this->errno); } return $rslt; } } The difficulty lies in calling methods such as bind_result on the wrapper. Constant-arity functions (e.g. bind_param) can be explicitly defined, allowing for pass-by-reference. bind_result, however, needs all arguments to be pass-by-reference. If you call bind_result on an instance of MySQLi_stmt_throwing as-is, the arguments are passed by value and the binding won't take. try { $id = Null; $stmt = $db->prepare('SELECT id FROM tbl WHERE ...'); $stmt->execute() $stmt->bind_result($id); // $id is still null at this point ... } catch (DBException $exc) { ... } Since the above classes are no longer in use, this question is merely a matter of curiosity. Alternate approaches to the wrapper classes are not relevant. Defining a method with a bunch of arguments taking Null default values is not correct (what if you define 20 arguments, but the function is called with 21?). Answers don't even need to be written in terms of MySQL_stmt_throwing; it exists simply to provide a concrete example.

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  • Scared of Calculus - Required to pass Differential Calculus as part of my Computer science major

    - by ke3pup
    Hi guys I'm finishing my Computer science degree in university but my fear of maths (lack of background knowledge) made me to leave all my maths units til' the very end which is now. i either take them on and pass or have to give up. I've passed all my programming units easily but knowing my poor maths skills won't do i've been staying clear of the maths units. I have to pass Differential Calculus and Linear Algebra first. With a help of book named "Linear Algebra: A Modern Introduction" i'm finding myself on track and i think i can pass the Linear Algebra unit. But with differential calculus i can't find a book to help me. They're either too advanced or just too simple for what i have to learn. The things i'm required to know for this units are: Set notation, the real number line, Complex numbers in cartesian form. Complex plane, modulus. Complex numbers in polar form. De Moivre’s Theorem. Complex powers and nth roots. Definition of ei? and ez for z complex. Applications to trigonometry. Revision of domain and range of a function Working in R3. Curves and surfaces. Functions of 2 variables. Level curves.Partial derivatives and tangent planes. The derivative as a difference quotient. Geometric significance of the derivative. Discussion of limit. Higher order partial derivatives. Limits of f(x,y). Continuity. Maxima and minima of f(x,y). The chain rule. Implicit differentiation. Directional derivatives and the gradient. Limit laws, l’Hoˆpital’s rule, composition law. Definition of sinh and cosh and their inverses. Taylor polynomials. The remainder term. Taylor series. Is there a book to help me get on track with the above? Being a student i can't buy too many books hence why i'm looking for a book that covers topics I need to know. The University library has a fairly limited collection which i took as loan but didn't find useful as it was too complex.

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  • Hidden Features of PHP?

    - by George Mauer
    EDIT: This didn't really start as a hidden features of PHP topic, but thats what it ended up as, so go nuts. I know this sounds like a point-whoring question but let me explain where I'm coming from. Out of college I got a job at a PHP shop. I worked there for a year and a half and thought that I had learned all there was to learn about programming. Then I got a job as a one-man internal development shop at a sizable corporation where all the work was in C#. In my commitment to the position I started reading a ton of blogs and books and quickly realized how wrong I was to think I knew everything. I learned about unit testing, dependency injection and decorator patterns, the design principle of loose coupling, the composition over inheritance debate, and so on and on and on - I am still very much absorbing it all. Needless to say my programming style has changed entirely in the last year. Now I find myself picking up a php project doing some coding for a friend's start-up and I feel completely constrained as opposed to programming in C#. It really bothers me that all variables at a class scope have to be referred to by appending '$this-' . It annoys me that none of the IDEs that I've tried have very good intellisense and that my SimpleTest unit tests methods have to start with the word 'test'. It drives me crazy that dynamic typing keeps me from specifying implicitly which parameter type a method expects, and that you have to write a switch statement to do method overloads. I can't stand that you can't have nested namespaces and have to use the :: operator to call the base class's constructor. Now I have no intention of starting a PHP vs C# debate, rather what I mean to say is that I'm sure there are some PHP features that I either don't know about or know about yet fail to use properly. I am set in my C# universe and having trouble seeing outside the glass bowl. So I'm asking, what are your favorite features of PHP? What are things you can do in it that you can't or are more difficult in the .Net languages?

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  • Get Ajax4JSF (a4j component) running on Glassfish

    - by yournamehere
    I'm trying to build an JEE6-application on Glassfish V3, using JSF 2.0, Weld, JPA2 and Maven. Now i'm having trouble getting a simple <a4j:support> running. This is the fragment of my little example. When typing something into the inputtext, the outputtext should automatically be updated. But nothing happens (not in Firefox, not in IE8). <ui:composition xmlns:a4j="https://ajax4jsf.dev.java.net/ajax" (...)> <h:inputText value="#{personHome.message}"> <a4j:support event="onkeyup" reRender="repeater"/> </h:inputText> <h:outputText id="repeater" value="#{personHome.message}"/> Beside that my example doesn't work, my problem is also that i don't really understand if i need a JSF implementation (MyFaces, Richfaces, Primefaces etc.) or not to use a4j elements. Is it "built-in" in glassfish? Until now, i only have the following dependencies i think i need in for JSF: <dependency> <groupId>com.sun.faces</groupId> <artifactId>jsf-api</artifactId> <version>2.0.2</version> </dependency> <dependency> <groupId>com.sun.faces</groupId> <artifactId>jsf-impl</artifactId> <version>2.0.2</version> </dependency>I'm trying to build an JEE6-application on Glassfish V3, using JSF 2.0, Weld, JPA2 and Maven. <dependency> <groupId>javax</groupId> <artifactId>javaee-api</artifactId> <version>6.0</version> <scope>provided</scope> </dependency> So... what do i have to do to get Ajax4JSF running on a simple JEE-App on Glassfish? Any help is highly appreciated!

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  • How to combine designable components with dependency injection

    - by Wim Coenen
    When creating a designable .NET component, you are required to provide a default constructor. From the IComponent documentation: To be a component, a class must implement the IComponent interface and provide a basic constructor that requires no parameters or a single parameter of type IContainer. This makes it impossible to do dependency injection via constructor arguments. (Extra constructors could be provided, but the designer would ignore them.) Some alternatives we're considering: Service Locator Don't use dependency injection, instead use the service locator pattern to acquire dependencies. This seems to be what IComponent.Site.GetService is for. I guess we could create a reusable ISite implementation (ConfigurableServiceLocator?) which can be configured with the necessary dependencies. But how does this work in a designer context? Dependency Injection via properties Inject dependencies via properties. Provide default instances if they are necessary to show the component in a designer. Document which properties need to be injected. Inject dependencies with an Initialize method This is much like injection via properties but it keeps the list of dependencies that need to be injected in one place. This way the list of required dependencies is documented implicitly, and the compiler will assists you with errors when the list changes. Any idea what the best practice is here? How do you do it? edit: I have removed "(e.g. a WinForms UserControl)" since I intended the question to be about components in general. Components are all about inversion of control (see section 8.3.1 of the UMLv2 specification) so I don't think that "you shouldn't inject any services" is a good answer. edit 2: It took some playing with WPF and the MVVM pattern to finally "get" Mark's answer. I see now that visual controls are indeed a special case. As for using non-visual components on designer surfaces, I think the .NET component model is fundamentally incompatible with dependency injection. It appears to be designed around the service locator pattern instead. Maybe this will start to change with the infrastructure that was added in .NET 4.0 in the System.ComponentModel.Composition namespace.

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  • MVVM Binding Orthogonal Aspects in Views e.g. Application Settings

    - by chibacity
    I have an application which I am developing using WPF\Prism\MVVM. All is going well and I have some pleasing MVVM implementations. However, in some of my views I would like to be able to bind application settings e.g. when a user reloads an application, the checkbox for auto-scrolling a grid should be checked in the state it was last time the user used the application. My view needs to bind to something that holds the "auto-scroll" setting state. I could put this on the view-model, but applications settings are orthogonal to the purpose of the view-model. The "auto-scroll" setting is controlling an aspect of the view. This setting is just an example. There will be quite a number of them and splattering my view-models with properties to represent application settings (so I can bind them) feels decidedly yucky. One view-model per view seems to be de rigeuer... What is best\usual practice here? Splatter my view-models with application settings? Have multiple view-models per view so settings can be represented in their own right? Split views so that controls can bind to an ApplicationSettingsViewModel? = too many views? Something else? Edit 1 To add a little more context, I am developing a UI with a tabbed interface. Each tab will host a single widget and there a variety of widgets. Each widget is a Prism composition of individual views. Some views are common amongst widgets e.g. a file picker view. Whilst each widget is composed of several views, as a whole, conceptually a widget has a single set of user settings e.g. last file selected, auto-scroll enabled, etc. These need to be persisted and retrieved\applied when the application starts again, and the widget views are created. My question is focused on the fact that conceptually a widget has a single set of user settings which is at right-angles to the fact that a widget consists of many views. Each view in the widget has it's own view-model (which works nicely and logically) but if I stick to a one view-model per view, I would have to splatter each view-model with user settings appropriate to it. This doesn't sound right ?!?

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  • IPhone avcomposition issue

    - by user346443
    Hi, Im trying to create a video that shows two videos one after the other using avcomposition on the iphone. This code works, however i can only see one of the videos for the entire duration of the newly created video - (void) startEdit{ AVMutableComposition* mixComposition = [AVMutableComposition composition]; NSString* a_inputFileName = @"export.mov"; NSString* a_inputFilePath = [NSTemporaryDirectory() stringByAppendingPathComponent:a_inputFileName]; NSURL* a_inputFileUrl = [NSURL fileURLWithPath:a_inputFilePath]; NSString* b_inputFileName = @"output.mov"; NSString* b_inputFilePath = [NSTemporaryDirectory() stringByAppendingPathComponent:b_inputFileName]; NSURL* b_inputFileUrl = [NSURL fileURLWithPath:b_inputFilePath]; NSString* outputFileName = @"outputFile.mov"; NSString* outputFilePath = [NSTemporaryDirectory() stringByAppendingPathComponent:outputFileName]; NSURL* outputFileUrl = [NSURL fileURLWithPath:outputFilePath]; if ([[NSFileManager defaultManager] fileExistsAtPath:outputFilePath]) [[NSFileManager defaultManager] removeItemAtPath:outputFilePath error:nil]; CMTime nextClipStartTime = kCMTimeZero; AVURLAsset* a_videoAsset = [[AVURLAsset alloc]initWithURL:a_inputFileUrl options:nil]; CMTimeRange a_timeRange = CMTimeRangeMake(kCMTimeZero,a_videoAsset.duration); AVMutableCompositionTrack *a_compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid]; [a_compositionVideoTrack insertTimeRange:a_timeRange ofTrack:[[a_videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] atTime:nextClipStartTime error:nil]; nextClipStartTime = CMTimeAdd(nextClipStartTime, a_timeRange.duration); AVURLAsset* b_videoAsset = [[AVURLAsset alloc]initWithURL:b_inputFileUrl options:nil]; CMTimeRange b_timeRange = CMTimeRangeMake(kCMTimeZero, b_videoAsset.duration); AVMutableCompositionTrack *b_compositionVideoTrack = [mixComposition addMutableTrackWithMediaType:AVMediaTypeVideo preferredTrackID:kCMPersistentTrackID_Invalid]; [b_compositionVideoTrack insertTimeRange:b_timeRange ofTrack:[[b_videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] atTime:nextClipStartTime error:nil]; AVAssetExportSession* _assetExport = [[AVAssetExportSession alloc] initWithAsset:mixComposition presetName:AVAssetExportPresetLowQuality]; _assetExport.outputFileType = @"com.apple.quicktime-movie"; _assetExport.outputURL = outputFileUrl; [_assetExport exportAsynchronouslyWithCompletionHandler: ^(void ) { [self saveVideoToAlbum:outputFilePath]; } ]; } - (void) saveVideoToAlbum:(NSString*)path{ if(UIVideoAtPathIsCompatibleWithSavedPhotosAlbum(path)){ UISaveVideoAtPathToSavedPhotosAlbum (path, self, @selector(video:didFinishSavingWithError: contextInfo:), nil); } } - (void) video: (NSString *) videoPath didFinishSavingWithError: (NSError *) error contextInfo: (void *) contextInfo { NSLog(@"Finished saving video with error: %@", error); } I've posted the whole code as it may help someone else. Shouldn't nextClipStartTime = CMTimeAdd(nextClipStartTime, a_timeRange.duration); [b_compositionVideoTrack insertTimeRange:b_timeRange ofTrack:[[b_videoAsset tracksWithMediaType:AVMediaTypeVideo] objectAtIndex:0] atTime:nextClipStartTime error:nil]; add the second video to the end of the first Cheers

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  • Subclassing and adding data members

    - by Marius
    I have an hierarchy of classes that looks like the following: class Critical { public: Critical(int a, int b) : m_a(a), m_b(b) { } virtual ~Critical() { } int GetA() { return m_a; } int GetB() { return m_b; } void SetA(int a) { m_a = a; } void SetB(int b) { m_b = b; } protected: int m_a; int m_b; }; class CriticalFlavor : public Critical { public: CriticalFlavor(int a, int b, int flavor) : Critical(a, b), m_flavor(flavor) { } virtual ~CriticalFlavor() { } int GetFlavor() { return m_flavor; } void SetFlavor(int flavor) { m_flavor = flavor; } protected: int m_flavor; }; class CriticalTwist : public Critical { public: CriticalTwist(int a, int b, int twist) : Critical(a, b), m_twist(twist) { } virtual ~CriticalTwist() { } int GetTwist() { return m_twist; } void SetTwist(int twist) { m_twist = twist; } protected: int m_twist; }; The above does not seem right to me in terms of the design and what bothers me the most is the fact that the addition of member variables seems to drive the interface of these classes (the real code that does the above is a little more complex but still embracing the same pattern). That will proliferate when in need for another "Critical" class that just adds some other property. Does this feel right to you? How could I refactor such code? An idea would be to have just a set of interfaces and use composition when it comes to the base object like the following: class Critical { public: virtual int GetA() = 0; virtual int GetB() = 0; virtual void SetA(int a) = 0; virtual void SetB(int b) = 0; }; class CriticalImpl { public: CriticalImpl(int a, int b) : m_a(a), m_b(b) { } ~CriticalImpl() { } int GetA() { return m_a; } int GetB() { return m_b; } void SetA(int a) { m_a = a; } void SetB(int b) { m_b = b; } private: int m_a; int m_b; }; class CriticalFlavor { public: virtual int GetFlavor() = 0; virtual void SetFlavor(int flavor) = 0; }; class CriticalFlavorImpl : public Critical, public CriticalFlavor { public: CriticalFlavorImpl(int a, int b, int flavor) : m_flavor(flavor), m_critical(new CriticalImpl(a, b)) { } ~CriticalFlavorImpl() { delete m_critical; } int GetFlavor() { return m_flavor; } void SetFlavor(int flavor) { m_flavor = flavor; } int GetA() { return m_critical-GetA(); } int GetB() { return m_critical-GetB(); } void SetA(int a) { m_critical-SetA(a); } void SetB(int b) { m_critical-SetB(b); } private: int m_flavor; CriticalImpl* m_critical; };

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  • A new MEF error I've not seen before -- "The export is not assignable to type..."

    - by Dave
    I was very surprised to get this error today, as it's one that I've never encountered before. Everything in the code looked okay, so I did some searches. The previous questions and their respective answers didn't help. This one was solved when the poster made sure his assembly references were consistent. I don't have this issue right now because I'm currently referencing another project in my solution. This one was solved when the poster was instructed to use ImportMany, but I am already using it (I think properly, too) to try to load multiple plugins This one was solved when the poster realized that there was a platform target mismatch. I've already gone through my projects to ensure that everything targets x86. So here's what I am trying to do. I have a plugin that owns a connection to a device. I might also need to be able to share that connection with another plugin. I decided that the cleanest way to do this was to create an interface that would allow the slave plugin to request its own connection to the device. Let's just call it IConnectionSharer. If the slave plugin does not need to borrow this connection and has its own, then it should use its own implementation of IConnectionSharer to connect to the device. My "master" plugin (the one that owns the connection to the device) implements IConnectionSharer. It also exports this via ExportAttribute. My "slave" plugin assembly defines a class that also implements and exports IConnectionSharer. When the application loads, the intent is for my slave plugin, via MEF, to enumerate all IConnectionSharers and store them in an IEnumerable<IConnectionSharer>. It does so like this: [ImportMany] public IEnumerable<IConnectionSharer> AllSharedConnections { get; set; } But during part composition, I get the error the export 'Company.MasterPlugin (ContractName="IConnectionSharer")' is not assignable to type 'IConnectionSharer'. The error message itself seems clear enough -- it's as if MEF thinks my master plugin doesn't inherit from IConnectionSharer... but it does! Can anyone suggest further debugging strategies? I'm going to start the painful process of single stepping through the MEF source.

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  • How can I represent a line of music notes in a way that allows fast insertion at any index?

    - by chairbender
    For "fun", and to learn functional programming, I'm developing a program in Clojure that does algorithmic composition using ideas from this theory of music called "Westergaardian Theory". It generates lines of music (where a line is just a single staff consisting of a sequence of notes, each with pitches and durations). It basically works like this: Start with a line consisting of three notes (the specifics of how these are chosen are not important). Randomly perform one of several "operations" on this line. The operation picks randomly from all pairs of adjacent notes that meet a certain criteria (for each pair, the criteria only depends on the pair and is independent of the other notes in the line). It inserts 1 or several notes (depending on the operation) between the chosen pair. Each operation has its own unique criteria. Continue randomly performing these operations on the line until the line is the desired length. The issue I've run into is that my implementation of this is quite slow, and I suspect it could be made faster. I'm new to Clojure and functional programming in general (though I'm experienced with OO), so I'm hoping someone with more experience can point out if I'm not thinking in a functional paradigm or missing out on some FP technique. My current implementation is that each line is a vector containing maps. Each map has a :note and a :dur. :note's value is a keyword representing a musical note like :A4 or :C#3. :dur's value is a fraction, representing the duration of the note (1 is a whole note, 1/4 is a quarter note, etc...). So, for example, a line representing the C major scale starting on C3 would look like this: [ {:note :C3 :dur 1} {:note :D3 :dur 1} {:note :E3 :dur 1} {:note :F3 :dur 1} {:note :G3 :dur 1} {:note :A4 :dur 1} {:note :B4 :dur 1} ] This is a problematic representation because there's not really a quick way to insert into an arbitrary index of a vector. But insertion is the most frequently performed operation on these lines. My current terrible function for inserting notes into a line basically splits the vector using subvec at the point of insertion, uses conj to join the first part + notes + last part, then uses flatten and vec to make them all be in a one-dimensional vector. For example if I want to insert C3 and D3 into the the C major scale at index 3 (where the F3 is), it would do this (I'll use the note name in place of the :note and :dur maps): (conj [C3 D3 E3] [C3 D3] [F3 G3 A4 B4]), which creates [C3 D3 E3 [C3 D3] [F3 G3 A4 B4]] (vec (flatten previous-vector)) which gives [C3 D3 E3 C3 D3 F3 G3 A4 B4] The run time of that is O(n), AFAIK. I'm looking for a way to make this insertion faster. I've searched for information on Clojure data structures that have fast insertion but haven't found anything that would work. I found "finger trees" but they only allow fast insertion at the start or end of the list. Edit: I split this into two questions. The other part is here.

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  • Encapsulating a Windows.Forms.Button

    - by devoured elysium
    I want to define a special kind of button that only allows two possible labels: "ON" and "OFF". I decided to inherit from a Windows.Forms.Button to implement this but now I don't know I how should enforce this rule. Should I just override the Text property like this? public override string Text { set { throw new InvalidOperationException("Invalid operation on StartStopButton!"); } } The problem I see with this is that I am breaking the contract that all buttons should have. If any code tries something like foreach (Button button in myForm) { button.Text = "123"; } they will get an Exception if I have any of my special buttons on the form, which is something that isn't expectable. First, because people think of properties just as "public" variables, not methods, second, because they are used to using and setting whatever they want to buttons without having to worry with Exceptions. Should I instead just make the set property do nothing? That could also lead to awkward results: myButton.Text = "abc"; MessageBox.Show(abc); //not "abc"! The general idea from the OO world is to in this kind of cases use Composition instead of inheritance. public class MySpecialButton : <Some class from System.Windows.Forms that already knows how to draw itself on forms> private Button button = new Button(); //I'd just draw this button on this class //and I'd then only show the fields I consider //relevant to the outside world. ... } But to make the Button "live" on a form it must inherit from some special class. I've looked on Control, but it seems to already have the Text property defined. I guess the ideal situation would be to inherit from some kind of class that wouldn't even have the Text property defined, but that'd have position, size, etc properties available. Upper in the hierarchy, after Control, we have Component, but that looks like a really raw class. Any clue about how to achieve this? I know this was a long post :( Thanks

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  • Multi-tenant ASP.NET MVC – Introduction

    - by zowens
    I’ve read a few different blogs that talk about multi-tenancy and how to resolve some of the issues surrounding multi-tenancy. What I’ve come to realize is that these implementations overcomplicate the issues and give only a muddy implementation! I’ve seen some really illogical code out there. I have recently been building a multi-tenancy framework for internal use at eagleenvision.net. Through this process, I’ve realized a few different techniques to make building multi-tenant applications actually quite easy. I will be posting a few different entries over the issue and my personal implementation. In this first post, I will discuss what multi-tenancy means and how my implementation will be structured.   So what’s the problem? Here’s the deal. Multi-tenancy is basically a technique of code-reuse of web application code. A multi-tenant application is an application that runs a single instance for multiple clients. Here the “client” is different URL bindings on IIS using ASP.NET MVC. The problem with different instances of the, essentially, same application is that you have to spin up different instances of ASP.NET. As the number of running instances of ASP.NET grows, so does the memory footprint of IIS. Stack Exchange shifted its architecture to multi-tenancy March. As the blog post explains, multi-tenancy saves cost in terms of memory utilization and physical disc storage. If you use the same code base for many applications, multi-tenancy just makes sense. You’ll reduce the amount of work it takes to synchronize the site implementations and you’ll thank your lucky stars later for choosing to use one application for multiple sites. Multi-tenancy allows the freedom of extensibility while relying on some pre-built code.   You’d think this would be simple. I have actually seen a real lack of reference material on the subject in terms of ASP.NET MVC. This is somewhat surprising given the number of users of ASP.NET MVC. However, I will certainly fill the void ;). Implementing a multi-tenant application takes a little thinking. It’s not straight-forward because the possibilities of implementation are endless. I have yet to see a great implementation of a multi-tenant MVC application. The only one that comes close to what I have in mind is Rob Ashton’s implementation (all the entries are listed on this page). There’s some really nasty code in there… something I’d really like to avoid. He has also written a library (MvcEx) that attempts to aid multi-tenant development. This code is even worse, in my honest opinion. Once I start seeing Reflection.Emit, I have to assume the worst :) In all seriousness, if his implementation makes sense to you, use it! It’s a fine implementation that should be given a look. At least look at the code. I will reference MvcEx going forward as a comparison to my implementation. I will explain why my approach differs from MvcEx and how it is better or worse (hopefully better).   Core Goals of my Multi-Tenant Implementation The first, and foremost, goal is to use Inversion of Control containers to my advantage. As you will see throughout this series, I pass around containers quite frequently and rely on their use heavily. I will be using StructureMap in my implementation. However, you could probably use your favorite IoC tool instead. <RANT> However, please don’t be stupid and abstract your IoC tool. Each IoC is powerful and by abstracting the capabilities, you’re doing yourself a real disservice. Who in the world swaps out IoC tools…? No one!</RANT> (It had to be said.) I will outline some of the goodness of StructureMap as we go along. This is really an invaluable tool in my tool belt and simple to use in my multi-tenant implementation. The second core goal is to represent a tenant as easily as possible. Just as a dependency container will be a first-class citizen, so will a tenant. This allows us to easily extend and use tenants. This will also allow different ways of “plugging in” tenants into your application. In my implementation, there will be a single dependency container for a single tenant. This will enable isolation of the dependencies of the tenant. The third goal is to use composition as a means to delegate “core” functions out to the tenant. More on this later.   Features In MvcExt, “Modules” are a code element of the infrastructure. I have simplified this concept and have named this “Features”. A feature is a simple element of an application. Controllers can be specified to have a feature and actions can have “sub features”. Each tenant can select features it needs and the other features will be hidden to the tenant’s users. My implementation doesn’t require something to be a feature. A controller can be common to all tenants. For example, (as you will see) I have a “Content” controller that will return the CSS, Javascript and Images for a tenant. This is common logic to all tenants and shouldn’t be hidden or considered a “feature”; Content is a core component.   Up next My next post will be all about the code. I will reveal some of the foundation to the way I do multi-tenancy. I will have posts dedicated to Foundation, Controllers, Views, Caching, Content and how to setup the tenants. Each post will be in-depth about the issues and implementation details, while adhering to my core goals outlined in this post. As always, comment with questions of DM me on twitter or send me an email.

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  • ASP.NET Controls – CommunityServer Captcha ControlAdapter, a practical case

    - by nmgomes
    The ControlAdapter is available since .NET framework version 2.0 and his main goal is to adapt and customize a control render in order to achieve a specific behavior or layout. This customization is done without changing the base control. A ControlAdapter is commonly used to custom render for specific platforms like Mobile. In this particular case the ControlAdapter was used to add a specific behavior to a Control. In this  post I will use one adapter to add a Captcha to all WeblogPostCommentForm controls within pontonetpt.com CommunityServer instance. The Challenge The ControlAdapter complexity is usually associated with the complexity/structure of is base control. This case is precisely one of those since base control dynamically load his content (controls) thru several ITemplate. Those of you who already played with ITemplate knows that while it is an excellent option for control composition it also brings to the table a big issue: “Controls defined within a template are not available for manipulation until they are instantiated inside another control.” While analyzing the WeblogPostCommentForm control I found that he uses the ITemplate technique to compose it’s layout and unfortunately I also found that the template content vary from theme to theme. This could have been a problem but luckily WeblogPostCommentForm control template content always contains a submit button with a well known ID (at least I can assume that there are a well known set of IDs). Using this submit button as anchor it’s possible to add the Captcha controls in the correct place. Another important finding was that WeblogPostCommentForm control inherits from the WrappedFormBase control which is the base control for all CommunityServer input forms. Knowing this inheritance link the main goal has changed to became the creation of a base ControlAdapter that  could be extended and customized to allow adding Captcha to: post comments form contact form user creation form. And, with this mind set, I decided to used the following ControlAdapter base class signature :public abstract class WrappedFormBaseCaptchaAdapter<T> : ControlAdapter where T : WrappedFormBase { }Great, but there are still many to do … Captcha The Captcha will be assembled with: A dynamically generated image with a set of random numbers A TextBox control where the image number will be inserted A Validator control to validate whether TextBox numbers match the image numbers This is a common Captcha implementation, is not rocket science and don’t bring any additional problem. The main problem, as told before, is to find the correct anchor control to ensure a correct Captcha control injection. The anchor control can vary by: target control  theme Implementation To support this dynamic scenario I choose to use the following implementation:private List<string> _validAnchorIds = null; protected virtual List<string> ValidAnchorIds { get { if (this._validAnchorIds == null) { this._validAnchorIds = new List<string>(); this._validAnchorIds.Add("btnSubmit"); } return this._validAnchorIds; } } private Control GetAnchorControl(T wrapper) { if (this.ValidAnchorIds == null || this.ValidAnchorIds.Count == 0) { throw new ArgumentException("Cannot be null or empty", "validAnchorNames"); } var q = from anchorId in this.ValidAnchorIds let anchorControl = CSControlUtility.Instance().FindControl(wrapper, anchorId) where anchorControl != null select anchorControl; return q.FirstOrDefault(); } I can now, using the ValidAnchorIds property, configure a set of valid anchor control  Ids. The GetAnchorControl method searches for a valid anchor control within the set of valid control Ids. Here, some of you may question why to use a LINQ To Objects expression, but the important here is to notice the usage of CSControlUtility.Instance().FindControl CommunityServer method. I want to build on top of CommunityServer not to reinvent the wheel. Assuming that an anchor control was found, it’s now possible to inject the Captcha at the correct place. This not something new, we do this all the time when creating server controls or adding dynamic controls:protected sealed override void CreateChildControls() { base.CreateChildControls(); if (this.IsCaptchaRequired) { T wrapper = base.Control as T; if (wrapper != null) { Control anchorControl = GetAnchorControl(wrapper); if (anchorControl != null) { Panel phCaptcha = new Panel {CssClass = "CommonFormField", ID = "Captcha"}; int index = anchorControl.Parent.Controls.IndexOf(anchorControl); anchorControl.Parent.Controls.AddAt(index, phCaptcha); CaptchaConfiguration.DefaultProvider.AddCaptchaControls( phCaptcha, GetValidationGroup(wrapper, anchorControl)); } } } } Here you can see a new entity in action: a provider. This is a CaptchaProvider class instance and is only goal is to create the Captcha itself and do everything else is needed to ensure is correct operation.public abstract class CaptchaProvider : ProviderBase { public abstract void AddCaptchaControls(Panel captchaPanel, string validationGroup); } You can create your own specific CaptchaProvider class to use different Captcha strategies including the use of existing Captcha services  like ReCaptcha. Once the generic ControlAdapter was created became extremely easy to created a specific one. Here is the specific ControlAdapter for the WeblogPostCommentForm control:public class WeblogPostCommentFormCaptchaAdapter : WrappedFormBaseCaptchaAdapter<WrappedFormBase> { #region Overriden Methods protected override List<string> ValidAnchorIds { get { List<string> validAnchorNames = base.ValidAnchorIds; validAnchorNames.Add("CommentSubmit"); return validAnchorNames; } } protected override string DefaultValidationGroup { get { return "CreateCommentForm"; } } #endregion Overriden Methods } Configuration This is the magic step. Without changing the original pages and keeping the application original assemblies untouched we are going to add a new behavior to the CommunityServer application. To glue everything together you must follow this steps: Add the following configuration to default.browser file:<?xml version='1.0' encoding='utf-8'?> <browsers> <browser refID="Default"> <controlAdapters> <!-- Adapter for the WeblogPostCommentForm control in order to add the Captcha and prevent SPAM comments --> <adapter controlType="CommunityServer.Blogs.Controls.WeblogPostCommentForm" adapterType="NunoGomes.CommunityServer.Components.WeblogPostCommentFormCaptchaAdapter, NunoGomes.CommunityServer" /> </controlAdapters> </browser> </browsers> Add the following configuration to web.config file:<configuration> <configSections> <!-- New section for Captcha providers configuration --> <section name="communityServer.Captcha" type="NunoGomes.CommunityServer.Captcha.Configuration.CaptchaSection" /> </configSections> <!-- Configuring a simple Captcha provider --> <communityServer.Captcha defaultProvider="simpleCaptcha"> <providers> <add name="simpleCaptcha" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProvider, NunoGomes.CommunityServer" imageUrl="~/captcha.ashx" enabled="true" passPhrase="_YourPassPhrase_" saltValue="_YourSaltValue_" hashAlgorithm="SHA1" passwordIterations="3" keySize="256" initVector="_YourInitVectorWithExactly_16_Bytes_" /> </providers> </communityServer.Captcha> <system.web> <httpHandlers> <!-- The Captcha Image handler used by the simple Captcha provider --> <add verb="GET" path="captcha.ashx" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProviderImageHandler, NunoGomes.CommunityServer" /> </httpHandlers> </system.web> <system.webServer> <handlers accessPolicy="Read, Write, Script, Execute"> <!-- The Captcha Image handler used by the simple Captcha provider --> <add verb="GET" name="captcha" path="captcha.ashx" type="NunoGomes.CommunityServer.Captcha.Providers.SimpleCaptchaProviderImageHandler, NunoGomes.CommunityServer" /> </handlers> </system.webServer> </configuration> Conclusion Building a ControlAdapter can be complex but the reward is his ability to allows us, thru configuration changes, to modify an application render and/or behavior. You can see this ControlAdapter in action here and here (anonymous required). A complete solution is available in “CommunityServer Extensions” Codeplex project.

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  • CodePlex Daily Summary for Sunday, May 30, 2010

    CodePlex Daily Summary for Sunday, May 30, 2010New ProjectsAviva Solutions C# Coding Guidelines: A set of C# coding guidelines, coding standards, layout rules, FxCop rulesets and (upcoming) custom FxCop and StyleCop rules for improving the over...BKWork: private project.classbook: du an trong vong 10 ngay. Nhom (Do Bao Linh, Phan Thanh Tai, Nguyen Dang Loc)Du an - 01: Du an mon thay LuongEndNote助手: EndNote Helper is a assistant tool for EndNote, which make your task of reference management more convinent. EndNote 助手是一个用于辅助EndNote进行文献管理的小工具,它可...Evoucher: Simple Evoucher Sales SystemFiddler Delayed Responses Extension: A fiddler extension that help developers delay the delivery of HTML Responses to applications. Some delay user stories: - Delivery of css to HTML ...Generic Entity Model 2: GEM2 is lightweight entity framework for building custom business solutions. It enables rapid approach to entity logic design, while offering out o...GY06: 这个是长大工院于2009年发起的项目,因为种种原因没有完成。JoshDOS: JoshDOS is a command line operating system kernel based off COSMOS. It can be booted from actual hardware and built in Visual Studio using .NET la...PhysicsFMUDeluxe.NET: Este projeto é desenvolvido com o intuíto de treinar o desenvolvimento de aplicações em C#. Ele contém ferramentas para cálculos de física e matemá...Reactor Services Platform: Reactor is a service composition and deployment grid that streamlines developing, composing, deploying and managing services. Reactor Services are ...SerafinApartment: Simple MVC 2 application for apartment rental. It is multingual booking system, that allows users to register, book and subscribe for notifications...Silverlight Audio Effect Box: This is a C# Silverlight 4 sample application which process audio sample in near real time. It allows to capture the default audio input device and...Smart Voice: Smart Voice let's you control Skype using your voice. It allows you to write messages, issue phone calls, etc. This application was developed think...WebDotNet - The minimalist web framework inspired by web.py: WebDotNet is an experiment in web frameworks. Inspired by the python web framework, web.py, it is an exercise in extreme minimalism in a framework...New ReleasesAcies: Acies - Alpha Build 0.0.7: Alpha release. Requires Microsoft XNA Framework Redistributable 3.1 (http://www.microsoft.com/downloads/details.aspx?FamilyID=53867a2a-e249-4560-...AdventureWorksLT 2008 Sample Database Script: AdventureWorksLT 2008 R2 DB Script: This script is based on latest download from the Sample database for SQL Server 2008 R2. The original download from the sample is approx 84 MB and ...ASP.NET Wiki Control: Release 1.3.1: - Removed ASP.NET Session dependency. BreadCrumbs will now work with sessions disabled. Can now also share a URL and have the breadcrumb appropriat...Aviva Solutions C# Coding Guidelines: Visual Studio 2010 Rule Sets: Rule Sets targetting different styles of projects.bvcms - Bellevue Church Management System: Source: This source was used to build the latest {church}.bvcms.comCC.Yacht: CC.Yacht 1.0.10.529: This is the initial release of CC.Yacht. Marked as beta since I don't have any testing/feedback beyond that of myself and my wife.Community Forums NNTP bridge: Community Forums NNTP Bridge V14: Release of the Community Forums NNTP Bridge to access the social and anwsers MS forums with a single, open source NNTP bridge. This release has add...Community Forums NNTP bridge: Community Forums NNTP Bridge V15: Release of the Community Forums NNTP Bridge to access the social and anwsers MS forums with a single, open source NNTP bridge. This release has add...Coronasoft Cryostasis scripting engine: CCSE v0.0.1.0 BETA: This is the 0.0.1.0 Beta Release. If you find any bugs Post them as a comment or in the Discussions tabEndNote助手: EndNote助手2.1.0..0: 去除了注册验证机制。Fiddler Delayed Responses Extension: v0.1: Version 0.1 of Fiddler Delayed Responses Extension. See ChangeLog for more information.Generic Entity Model 2: GEM2 build 52510: This is first BETA release of GEM2! Following implementation is still missing from initial plan: Detailed documentation MySQL operational databa...JoshDOS: JoshDOS Souce: This is the souce for the JoshDOS 1.0 OS kernel. You need the COSMOS user kit to use.JoshDOS: Shell Version 1.0: Whats in this download *JoshDOS user kit *JoshDOS VStudio starter kit *JoshDOS documentation Note: You will need the COSMOS user kit to start deve...miniTodo: mini Todo version 0.3: Todo完了時に音が出なかったのを修正Model Virtual Casting - ASPItalia.com: Model Virtual Casting 0.2: Model Virtual Casting 0.2Questa seconda release di ModelVC è corrispondente a quella mostrata in occasione della Real Code Conference 4.0 tenutasi ...PhysicsFMUDeluxe.NET: PhysicsFMUDeluxe.NET - Setup: Primeira versão pública do PhysicsFMUDeluxe.NETSilverlight Audio Effect Box: Echo Box 1.0: First realease - zip contains : web page + xap file :Smart Voice: Smart Voice 0.1: Here is the first alpha release of Smart Voice. Please remember this was done for a curricular unit project at my university and i understand that ...StyleCop Contrib: Custom rules v0.2: This release of the custom rules target StyleCop 4.3.3. Included rules are: Spacing Rules - NoTrailingWhiteSpace - IndentUsingTabs Ordering Rules ...System.ComponentModel.DataAnnotations Contrib: 0.2.46280.0: Built with Visual Studio 2010/.Net 4.0. Compiled from source code changeset 46280.VB Styler: VB Styler Suite V 1.3.0.0: This is the newest version of the VB Styler. Here are the new features. New Imaging ColorPicker A template for getting colors via sliders ColorR...VCC: Latest build, v2.1.30529.0: Automatic drop of latest buildWPF Application Framework (WAF): WPF Application Framework (WAF) 1.0.0.90 RC: Version: 1.0.0.90 (Release Candidate): This release contains the source code of the WPF Application Framework (WAF) and the sample applications. ...XNA Collision Detection: XNA Collision Detection Sample Program: I have coded a compact program which shows the collision detection working, and provides a camera class for rendering and moving the "player." Agai...Most Popular ProjectsRawrWBFS ManagerAJAX Control ToolkitMicrosoft SQL Server Product Samples: DatabaseSilverlight ToolkitWindows Presentation Foundation (WPF)patterns & practices – Enterprise LibraryMicrosoft SQL Server Community & SamplesPHPExcelASP.NETMost Active ProjectsAStar.netpatterns & practices – Enterprise LibraryCommunity Forums NNTP bridgeBlogEngine.NETGMap.NET - Great Maps for Windows Forms & PresentationIonics Isapi Rewrite FilterRawrCustomer Portal Accelerator for Microsoft Dynamics CRMFacebook Developer ToolkitPAP

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  • WCF – interchangeable data-contract types

    - by nmarun
    In a WSDL based environment, unlike a CLR-world, we pass around the ‘state’ of an object and not the reference of an object. Well firstly, what does ‘state’ mean and does this also mean that we can send a struct where a class is expected (or vice-versa) as long as their ‘state’ is one and the same? Let’s see. So I have an operation contract defined as below: 1: [ServiceContract] 2: public interface ILearnWcfServiceExtend : ILearnWcfService 3: { 4: [OperationContract] 5: Employee SaveEmployee(Employee employee); 6: } 7:  8: [ServiceBehavior] 9: public class LearnWcfService : ILearnWcfServiceExtend 10: { 11: public Employee SaveEmployee(Employee employee) 12: { 13: employee.EmployeeId = 123; 14: return employee; 15: } 16: } Quite simplistic operation there (which translates to ‘absolutely no business value’). Now, the data contract Employee mentioned above is a struct. 1: public struct Employee 2: { 3: public int EmployeeId { get; set; } 4:  5: public string FName { get; set; } 6: } After compilation and consumption of this service, my proxy (in the Reference.cs file) looks like below (I’ve ignored the rest of the details just to avoid unwanted confusion): 1: public partial struct Employee : System.Runtime.Serialization.IExtensibleDataObject, System.ComponentModel.INotifyPropertyChanged I call the service with the code below: 1: private static void CallWcfService() 2: { 3: Employee employee = new Employee { FName = "A" }; 4: Console.WriteLine("IsValueType: {0}", employee.GetType().IsValueType); 5: Console.WriteLine("IsClass: {0}", employee.GetType().IsClass); 6: Console.WriteLine("Before calling the service: {0} - {1}", employee.EmployeeId, employee.FName); 7: employee = LearnWcfServiceClient.SaveEmployee(employee); 8: Console.WriteLine("Return from the service: {0} - {1}", employee.EmployeeId, employee.FName); 9: } The output is: I now change my Employee type from a struct to a class in the proxy class and run the application: 1: public partial class Employee : System.Runtime.Serialization.IExtensibleDataObject, System.ComponentModel.INotifyPropertyChanged { The output this time is: The state of an object implies towards its composition, the properties and the values of these properties and not based on whether it is a reference type (class) or a value type (struct). And as shown above, we’re actually passing an object by its state and not by reference. Continuing on the same topic of ‘type-interchangeability’, WCF treats two data contracts as equivalent if they have the same ‘wire-representation’. We can do so using the DataContract and DataMember attributes’ Name property. 1: [DataContract] 2: public struct Person 3: { 4: [DataMember] 5: public int Id { get; set; } 6:  7: [DataMember] 8: public string FirstName { get; set; } 9: } 10:  11: [DataContract(Name="Person")] 12: public class Employee 13: { 14: [DataMember(Name = "Id")] 15: public int EmployeeId { get; set; } 16:  17: [DataMember(Name="FirstName")] 18: public string FName { get; set; } 19: } I’ve created two data contracts with the exact same wire-representation. Just remember that the names and the types of data members need to match to be considered equivalent. The question then arises as to what gets generated in the proxy class. Despite us declaring two data contracts (Person and Employee), only one gets emitted – Person. This is because we’re saying that the Employee type has the same wire-representation as the Person type. Also that the signature of the SaveEmployee operation gets changed on the proxy side: 1: [System.CodeDom.Compiler.GeneratedCodeAttribute("System.ServiceModel", "4.0.0.0")] 2: [System.ServiceModel.ServiceContractAttribute(ConfigurationName="ServiceProxy.ILearnWcfServiceExtend")] 3: public interface ILearnWcfServiceExtend 4: { 5: [System.ServiceModel.OperationContractAttribute(Action="http://tempuri.org/ILearnWcfServiceExtend/SaveEmployee", ReplyAction="http://tempuri.org/ILearnWcfServiceExtend/SaveEmployeeResponse")] 6: ClientApplication.ServiceProxy.Person SaveEmployee(ClientApplication.ServiceProxy.Person employee); 7: } But, on the service side, the SaveEmployee still accepts and returns an Employee data contract. 1: [ServiceBehavior] 2: public class LearnWcfService : ILearnWcfServiceExtend 3: { 4: public Employee SaveEmployee(Employee employee) 5: { 6: employee.EmployeeId = 123; 7: return employee; 8: } 9: } Despite all these changes, our output remains the same as the last one: This is type-interchangeability at work! Here’s one more thing to ponder about. Our Person type is a struct and Employee type is a class. Then how is it that the Person type got emitted as a ‘class’ in the proxy? It’s worth mentioning that WSDL describes a type called Employee and does not say whether it is a class or a struct (see the SOAP message below): 1: <soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" 2: xmlns:tem="http://tempuri.org/" 3: xmlns:ser="http://schemas.datacontract.org/2004/07/ServiceApplication"> 4: <soapenv:Header/> 5: <soapenv:Body> 6: <tem:SaveEmployee> 7: <!--Optional:--> 8: <tem:employee> 9: <!--Optional:--> 10: <ser:EmployeeId>?</ser:EmployeeId> 11: <!--Optional:--> 12: <ser:FName>?</ser:FName> 13: </tem:employee> 14: </tem:SaveEmployee> 15: </soapenv:Body> 16: </soapenv:Envelope> There are some differences between how ‘Add Service Reference’ and the svcutil.exe generate the proxy class, but turns out both do some kind of reflection and determine the type of the data contract and emit the code accordingly. So since the Employee type is a class, the proxy ‘Person’ type gets generated as a class. In fact, reflecting on svcutil.exe application, you’ll see that there are a couple of places wherein a flag actually determines a type as a class or a struct. One example is in the ExportISerializableDataContract method in the System.Runtime.Serialization.CodeExporter class. Seems like these flags have a say in deciding whether the type gets emitted as a struct or a class. This behavior is different if you use the WSDL tool though. WSDL tool does not do any kind of reflection of the data contract / serialized type, it emits the type as a class by default. You can check this using the two command lines below:   Note to self: Remember ‘state’ and type-interchangeability when traversing through the WSDL planet!

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  • CodePlex Daily Summary for Monday, July 01, 2013

    CodePlex Daily Summary for Monday, July 01, 2013Popular ReleasesQuickMon: Version 2.10.3: Mainly just a service release - no major changes. Toolbar buttons on main and config window can now be re-arrange (using ALT key) Added property to disable corrective scriptsDotNetNuke® IFrame: IFrame 04.05.00: New DNN6/7 Manifest file and Azure Compatibility.VidCoder: 1.5.2 Beta: Fixed crash on presets with an invalid bitrate.Roadkill - .NET Wiki engine: Roadkill v1.7: New features in 1.7: New file manager: Multiple file uploads Drag and drop uploads Delete folders (admins only) Delete files (admins only) (Experimental) Syntaxhighlighting custom variable (using https://github.com/alexgorbatchev/SyntaxHighlighter) - use [[[code lang=c#|your code here]]] (Experimental) MathJax custom variable - use [[[Mathjax]]] and $$your tex$$ on the page. Improved black bar theme Site speed improvements for Javascript/CSS files - now just two files files ea...Download Sharepoint Solution package: Release 4: version updated for SP2013WinRT XAML Toolkit: WinRT XAML Toolkit - 1.5: WinRT XAML Toolkit based on the Windows 8.0 and 8.1 Preview SDKs. Do not download the source code from here if you are looking for latest updates! You can download the latest source from the SOURCE CODE page. For compiled version use NuGet. You can add it to your project in Visual Studio by going to View/Other Windows/Package Manager Console and entering: PM> Install-Package winrtxamltoolkit Features Attachable Behaviors AwaitableUI extensions Composition library for visual tree rende...Gardens Point LEX: Gardens Point LEX version 1.2.1: The main distribution is a zip file. This contains the binary executable, documentation, source code and the examples. ChangesVersion 1.2.1 has new facilities for defining and manipulating character classes. These changes make the construction of large Unicode character classes more convenient. The runtime code for performing automaton backup has been re-implemented, and is now faster for scanners that need backup. Source CodeThe distribution contains a complete VS2010 project for the appli...ZXMAK2: Version 2.7.5.7: - fix TZX emulation (Bruce Lee, Zynaps) - fix ATM 16 colors for border - add memory module PROFI 512K; add PROFI V03 rom image; fix PROFI 3.XX configTwitter image Downloader: Twitter Image Downloader 2 with Installer: Application file with Install shield and Dot Net 4.0 redistributableUltimate Music Tagger: Ultimate Music Tagger 1.0.0.0: First release of Ultimate Music TaggerBlackJumboDog: Ver5.9.2: 2013.06.28 Ver5.9.2 (1) ??????????(????SMTP?????)?????????? (2) HTTPS???????????Outlook 2013 Add-In: Configuration Form: This new version includes the following changes: - Refactored code a bit. - Removing configuration from main form to gain more space to display items. - Moved configuration to separate form. You can click the little "gear" icon to access the configuration form (still very simple). - Added option to show past day appointments from the selected day (previous in time, that is). - Added some tooltips. You will have to uninstall the previous version (add/remove programs) if you had installed it ...Terminals: Version 3.0 - Release: Changes since version 2.0:Choose 100% portable or installed version Removed connection warning when running RDP 8 (Windows 8) client Fixed Active directory search Extended Active directory search by LDAP filters Fixed single instance mode when running on Windows Terminal server Merged usage of Tags and Groups Added columns sorting option in tables No UAC prompts on Windows 7 Completely new file persistence data layer New MS SQL persistence layer (Store data in SQL database)...NuGet: NuGet 2.6: Released June 26, 2013. Release notes: http://docs.nuget.org/docs/release-notes/nuget-2.6Python Tools for Visual Studio: 2.0 Beta: We’re pleased to announce the release of Python Tools for Visual Studio 2.0 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 CPython/IronPython, Edit/Intellisense/Debug/Profile, Cloud, HPC, IPython, and cross platform debugging support. For a quick overview of the general IDE experience, please watch this video: http://www.youtube.com/watch?v=TuewiStN...Player Framework by Microsoft: Player Framework for Windows 8 and WP8 (v1.3 beta): Preview: New MPEG DASH adaptive streaming plugin for Windows Azure Media Services Preview: New Ultraviolet CFF plugin. Preview: New WP7 version with WP8 compatibility. (source code only) Source code is now available via CodePlex Git Misc bug fixes and improvements: WP8 only: Added optional fullscreen and mute buttons to default xaml JS only: protecting currentTime from returning infinity. Some videos would cause currentTime to be infinity which could cause errors in plugins expectin...AssaultCube Reloaded: 2.5.8: SERVER OWNERS: note that the default maprot has changed once again. Linux has Ubuntu 11.10 32-bit precompiled binaries and Ubuntu 10.10 64-bit precompiled binaries, but you can compile your own as it also contains the source. If you are using Mac or other operating systems, please wait while we continue to try to package for those OSes. Or better yet, try to compile it. If it fails, download a virtual machine. The server pack is ready for both Windows and Linux, but you might need to compi...Microsoft Ajax Minifier: Microsoft Ajax Minifier 4.95: update parser to allow for CSS3 calc( function to nest. add recognition of -pponly (Preprocess-Only) switch in AjaxMinManifestTask build task. Fix crashing bug in EXE when processing a manifest file using the -xml switch and an error message needs to be displayed (like a missing input file). Create separate Clean and Bundle build tasks for working with manifest files (AjaxMinManifestCleanTask and AjaxMinBundleTask). Removed the IsCleanOperation from AjaxMinManifestTask -- use AjaxMinMan...VG-Ripper & PG-Ripper: VG-Ripper 2.9.44: changes NEW: Added Support for "ImgChili.net" links FIXED: Auto UpdaterDocument.Editor: 2013.25: What's new for Document.Editor 2013.25: Improved Spell Check support Improved User Interface Minor Bug Fix's, improvements and speed upsNew ProjectsAerCloud.net Client - Java, Linux & Windows: This project source code provides a step by step guide for using AerCloud.net Framework as a Service API. For more information please visit http://www.aercloudAmiClient – Asterisk Manager Interface (AMI) client based on the Rx Framework: Asterisk Manager Interface (AMI) client based on the Rx Frameworkbaidupan: cdcddddC#??????: C#??????ImageHelper: imagehelperIP switcher: IP switcher is a simple tool for switching settings, and store presets, on networkadapters.MastersProject: A MS project with a goal of creating a fully Code Contracts verified physics engine and a relatively simple game that uses it.Multiplatform card game: Example multipatform project.PhoneTools: A collection of tools designed to help developers create beautiful Windows Phone 8 apps.rodidexter: lllSharePoint 2013 List Item Encryption: This coding exercise project enables you to encrypt/decrypt list item text field in the browser using industry standard algorithms.tvaSoft: simulation, rotor dynamics, Finite Element Analisys, FEM, ODE, torsional vibration, flexural vibrationX3DML Project: X3DML is an xml-based markup language that defines rules for modeling 3D scenes from a tag-based document. It may be usefull in 3D web design and VR.zhuang-tfs: zhuang tfs

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  • SQL SERVER – Using expressor Composite Types to Enforce Business Rules

    - by pinaldave
    One of the features that distinguish the expressor Data Integration Platform from other products in the data integration space is its concept of composite types, which provide an effective and easily reusable way to clearly define the structure and characteristics of data within your application.  An important feature of the composite type approach is that it allows you to easily adjust the content of a record to its ultimate purpose.  For example, a record used to update a row in a database table is easily defined to include only the minimum set of columns, that is, a value for the key column and values for only those columns that need to be updated. Much like a class in higher level programming languages, you can also use the composite type as a way to enforce business rules onto your data by encapsulating a datum’s name, data type, and constraints (for example, maximum, minimum, or acceptable values) as a single entity, which ensures that your data can not assume an invalid value.  To what extent you use this functionality is a decision you make when designing your application; the expressor design paradigm does not force this approach on you. Let’s take a look at how these features are used.  Suppose you want to create a group of applications that maintain the employee table in your human resources database. Your table might have a structure similar to the HumanResources.Employee table in the AdventureWorks database.  This table includes two columns, EmployeID and rowguid, that are maintained by the relational database management system; you cannot provide values for these columns when inserting new rows into the table. Additionally, there are columns such as VacationHours and SickLeaveHours that you might choose to update for all employees on a monthly basis, which justifies creation of a dedicated application. By creating distinct composite types for the read, insert and update operations against this table, you can more easily manage this table’s content. When developing this application within expressor Studio, your first task is to create a schema artifact for the database table.  This process is completely driven by a wizard, only requiring that you select the desired database schema and table.  The resulting schema artifact defines the mapping of result set records to a record within the expressor data integration application.  The structure of the record within the expressor application is a composite type that is given the default name CompositeType1.  As you can see in the following figure, all columns from the table are included in the result set and mapped to an identically named attribute in the default composite type. If you are developing an application that needs to read this table, perhaps to prepare a year-end report of employees by department, you would probably not be interested in the data in the rowguid and ModifiedDate columns.  A typical approach would be to drop this unwanted data in a downstream operator.  But using an alternative composite type provides a better approach in which the unwanted data never enters your application. While working in expressor  Studio’s schema editor, simply create a second composite type within the same schema artifact, which you could name ReadTable, and remove the attributes corresponding to the unwanted columns. The value of an alternative composite type is even more apparent when you want to insert into or update the table.  In the composite type used to insert rows, remove the attributes corresponding to the EmployeeID primary key and rowguid uniqueidentifier columns since these values are provided by the relational database management system. And to update just the VacationHours and SickLeaveHours columns, use a composite type that includes only the attributes corresponding to the EmployeeID, VacationHours, SickLeaveHours and ModifiedDate columns. By specifying this schema artifact and composite type in a Write Table operator, your upstream application need only deal with the four required attributes and there is no risk of unintentionally overwriting a value in a column that does not need to be updated. Now, what about the option to use the composite type to enforce business rules?  If you review the composition of the default composite type CompositeType1, you will note that the constraints defined for many of the attributes mirror the table column specifications.  For example, the maximum number of characters in the NationaIDNumber, LoginID and Title attributes is equivalent to the maximum width of the target column, and the size of the MaritalStatus and Gender attributes is limited to a single character as required by the table column definition.  If your application code leads to a violation of these constraints, an error will be raised.  The expressor design paradigm then allows you to handle the error in a way suitable for your application.  For example, a string value could be truncated or a numeric value could be rounded. Moreover, you have the option of specifying additional constraints that support business rules unrelated to the table definition. Let’s assume that the only acceptable values for marital status are S, M, and D.  Within the schema editor, double-click on the MaritalStatus attribute to open the Edit Attribute window.  Then click the Allowed Values checkbox and enter the acceptable values into the Constraint Value text box. The schema editor is updated accordingly. There is one more option that the expressor semantic type paradigm supports.  Since the MaritalStatus attribute now clearly specifies how this type of information should be represented (a single character limited to S, M or D), you can convert this attribute definition into a shared type, which will allow you to quickly incorporate this definition into another composite type or into the description of an output record from a transform operator. Again, double-click on the MaritalStatus attribute and in the Edit Attribute window, click Convert, which opens the Share Local Semantic Type window that you use to name this shared type.  There’s no requirement that you give the shared type the same name as the attribute from which it was derived.  You should supply a name that makes it obvious what the shared type represents. In this posting, I’ve overviewed the expressor semantic type paradigm and shown how it can be used to make your application development process more productive.  The beauty of this feature is that you choose when and to what extent you utilize the functionality, but I’m certain that if you opt to follow this approach your efforts will become more efficient and your work will progress more quickly.  As always, I encourage you to download and evaluate expressor Studio for your current and future data integration needs. Reference: Pinal Dave (http://blog.SQLAuthority.com) Filed under: CodeProject, Pinal Dave, PostADay, SQL, SQL Authority, SQL Documentation, SQL Query, SQL Server, SQL Tips and Tricks, SQLServer, T SQL, Technology

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  • Who could ask for more with LESS CSS? (Part 3 of 3&ndash;Clrizr)

    - by ToString(theory);
    Welcome back!  In the first two posts in this series, I covered some of the awesome features in CSS precompilers such as SASS and LESS, as well as how to get an initial project setup up and running in ASP.Net MVC 4. In this post, I will cover an actual advanced example of using LESS in a project, and show some of the great productivity features we gain from its usage. Introduction In the first post, I mentioned two subjects that I will be using in this example – constants, and color functions.  I’ve always enjoyed using online color scheme utilities such as Adobe Kuler or Color Scheme Designer to come up with a scheme based off of one primary color.  Using these tools, and requesting a complementary scheme you can get a couple of shades of your primary color, and a couple of shades of a complementary/accent color to display. Because there is no way in regular css to do color operations or store variables, there was no way to accomplish something like defining a primary color, and have a site theme cascade off of that.  However with tools such as LESS, that impossibility becomes a reality!  So, if you haven’t guessed it by now, this post is on the creation of a plugin/module/less file to drop into your project, plugin one color, and have your primary theme cascade from it.  I only went through the trouble of creating a module for getting Complementary colors.  However, it wouldn’t be too much trouble to go through other options such as Triad or Monochromatic to get a module that you could use off of that. Step 1 – Analysis I decided to mimic Adobe Kuler’s Complementary theme algorithm as I liked its simplicity and aesthetics.  Color Scheme Designer is great, but I do believe it can give you too many color options, which can lead to chaos and overload.  The first thing I had to check was if the complementary values for the color schemes were actually hues rotated by 180 degrees at all times – they aren’t.  Apparently Adobe applies some variance to the complementary colors to get colors that are actually more aesthetically appealing to users.  So, I opened up Excel and began to plot complementary hues based on rotation in increments of 10: Long story short, I completed the same calculations for Hue, Saturation, and Lightness.  For Hue, I only had to record the Complementary hue values, however for saturation and lightness, I had to record the values for ALL of the shades.  Since the functions were too complicated to put into LESS since they aren’t constant/linear, but rather interval functions, I instead opted to extrapolate the HSL values using the trendline function for each major interval, onto intervals of spacing 1. For example, using the hue extraction, I got the following values: Interval Function 0-60 60-140 140-270 270-360 Saturation and Lightness were much worse, but in the end, I finally had functions for all of the intervals, and then went the route of just grabbing each shades value in intervals of 1.  Step 2 – Mapping I declared variable names for each of these sections as something that shouldn’t ever conflict with a variable someone would define in their own file.  After I had each of the values, I extracted the values and put them into files of their own for hue variables, saturation variables, and lightness variables…  Example: /*HUE CONVERSIONS*/@clrizr-hue-source-0deg: 133.43;@clrizr-hue-source-1deg: 135.601;@clrizr-hue-source-2deg: 137.772;@clrizr-hue-source-3deg: 139.943;@clrizr-hue-source-4deg: 142.114;.../*SATURATION CONVERSIONS*/@clrizr-saturation-s2SV0px: 0;@clrizr-saturation-s2SV1px: 0;@clrizr-saturation-s2SV2px: 0;@clrizr-saturation-s2SV3px: 0;@clrizr-saturation-s2SV4px: 0;.../*LIGHTNESS CONVERSIONS*/@clrizr-lightness-s2LV0px: 30;@clrizr-lightness-s2LV1px: 31;@clrizr-lightness-s2LV2px: 32;@clrizr-lightness-s2LV3px: 33;@clrizr-lightness-s2LV4px: 34;...   In the end, I have 973 lines of mapping/conversion from source HSL to shade HSL for two extra primary shades, and two complementary shades. The last bit of the work was the file to compose each of the shades from these mappings. Step 3 – Clrizr Mapper The final step was the hardest to overcome as I was still trying to understand LESS to its fullest extent.  Imports As mentioned previously, I had separated the HSL mappings into different files, so the first necessary step is to import those for use into the Clrizr plugin: @import url("hue.less");@import url("saturation.less");@import url("lightness.less"); Extract Component Values For Each Shade Next, I extracted the necessary information for each shade HSL before shade composition: @clrizr-input-saturation: 1px+floor(saturation(@clrizr-input))-1;@clrizr-input-lightness: 1px+floor(lightness(@clrizr-input))-1; @clrizr-complementary-hue: formatstring("clrizr-hue-source-{0}", ceil(hue(@clrizr-input))); @clrizr-primary-2-saturation: formatstring("clrizr-saturation-s2SV{0}",@clrizr-input-saturation);@clrizr-primary-1-saturation: formatstring("clrizr-saturation-s1SV{0}",@clrizr-input-saturation);@clrizr-complementary-1-saturation: formatstring("clrizr-saturation-c1SV{0}",@clrizr-input-saturation); @clrizr-primary-2-lightness: formatstring("clrizr-lightness-s2LV{0}",@clrizr-input-lightness);@clrizr-primary-1-lightness: formatstring("clrizr-lightness-s1LV{0}",@clrizr-input-lightness);@clrizr-complementary-1-lightness: formatstring("clrizr-lightness-c1LV{0}",@clrizr-input-lightness); Here, you can see a couple of odd things…  On the first line, I am using operations to add units to the saturation and lightness.  This is due to some limitations in the operations that would give me saturation or lightness in %, which can’t be in a variable name.  So, I use first add 1px to it, which casts the result of the following functions as px instead of %, and then at the end, I remove that pixel.  You can also see here the formatstring method which is exactly what it sounds like – something like String.Format(string str, params object[] obj). Get Primary & Complementary Shades Now that I have components for each of the different shades, I can now compose them into each of their pieces.  For this, I use the @@ operator which will look for a variable with the name specified in a string, and then call that variable: @clrizr-primary-2: hsl(hue(@clrizr-input), @@clrizr-primary-2-saturation, @@clrizr-primary-2-lightness);@clrizr-primary-1: hsl(hue(@clrizr-input), @@clrizr-primary-1-saturation, @@clrizr-primary-1-lightness);@clrizr-primary: @clrizr-input;@clrizr-complementary-1: hsl(@@clrizr-complementary-hue, @@clrizr-complementary-1-saturation, @@clrizr-complementary-1-lightness);@clrizr-complementary-2: hsl(@@clrizr-complementary-hue, saturation(@clrizr-input), lightness(@clrizr-input)); That’s is it, for the most part.  These variables now hold the theme for the one input color – @clrizr-input.  However, I have one last addition… Perceptive Luminance Well, after I got the colors, I decided I wanted to also get the best font color that would go on top of it.  Black or white depending on light or dark color.  Now I couldn’t just go with checking the lightness, as that is half the story.  You see, the human eye doesn’t see ALL colors equally well but rather has more cells for interpreting green light compared to blue or red.  So, using the ratio, we can calculate the perceptive luminance of each of the shades, and get the font color that best matches it! @clrizr-perceptive-luminance-ps2: round(1 - ( (0.299 * red(@clrizr-primary-2) ) + ( 0.587 * green(@clrizr-primary-2) ) + (0.114 * blue(@clrizr-primary-2)))/255)*255;@clrizr-perceptive-luminance-ps1: round(1 - ( (0.299 * red(@clrizr-primary-1) ) + ( 0.587 * green(@clrizr-primary-1) ) + (0.114 * blue(@clrizr-primary-1)))/255)*255;@clrizr-perceptive-luminance-ps: round(1 - ( (0.299 * red(@clrizr-primary) ) + ( 0.587 * green(@clrizr-primary) ) + (0.114 * blue(@clrizr-primary)))/255)*255;@clrizr-perceptive-luminance-pc1: round(1 - ( (0.299 * red(@clrizr-complementary-1)) + ( 0.587 * green(@clrizr-complementary-1)) + (0.114 * blue(@clrizr-complementary-1)))/255)*255;@clrizr-perceptive-luminance-pc2: round(1 - ( (0.299 * red(@clrizr-complementary-2)) + ( 0.587 * green(@clrizr-complementary-2)) + (0.114 * blue(@clrizr-complementary-2)))/255)*255; @clrizr-col-font-on-primary-2: rgb(@clrizr-perceptive-luminance-ps2, @clrizr-perceptive-luminance-ps2, @clrizr-perceptive-luminance-ps2);@clrizr-col-font-on-primary-1: rgb(@clrizr-perceptive-luminance-ps1, @clrizr-perceptive-luminance-ps1, @clrizr-perceptive-luminance-ps1);@clrizr-col-font-on-primary: rgb(@clrizr-perceptive-luminance-ps, @clrizr-perceptive-luminance-ps, @clrizr-perceptive-luminance-ps);@clrizr-col-font-on-complementary-1: rgb(@clrizr-perceptive-luminance-pc1, @clrizr-perceptive-luminance-pc1, @clrizr-perceptive-luminance-pc1);@clrizr-col-font-on-complementary-2: rgb(@clrizr-perceptive-luminance-pc2, @clrizr-perceptive-luminance-pc2, @clrizr-perceptive-luminance-pc2); Conclusion That’s it!  I have posted a project on clrizr.codePlex.com for this, and included a testing page for you to test out how it works.  Feel free to use it in your own project, and if you have any questions, comments or suggestions, please feel free to leave them here as a comment, or on the contact page!

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  • Vista/7: How to get glass color?

    - by Ian Boyd
    How do you use DwmGetColorizationColor? The documentation says it returns two values: a 32-bit 0xAARRGGBB containing the color used for glass composition a boolean parameter that is true "if the color is an opaque blend" (whatever that means) Here's a color that i like, a nice puke green: You can notice the color is greeny, and the translucent title bar (against a white background) shows the snot color very clearly: i try to get the color from Windows: DwmGetColorizationColor(dwCcolorization, bIsOpaqueBlend); And i get dwColorization: 0x0D0A0F04 bIsOpaqueBlend: false According to the documentation this value is of the format AARRGGBB, and so contains: AA: 0x0D (13) RR: 0x0A (10) GG: 0x0F (15) BB: 0x04 (4) This supposedly means that the color is (10, 15, 4), with an opacity of ~5.1%. But if you actually look at this RGB value, it's nowhere near my desired snot green. Here is (10, 15, 4) with zero opacity (the original color), and (10,15,4) with 5% opacity against a white/checkerboard background: So the question is: How to get glass color in Windows Vista/7? i tried using DwmGetColorizationColor, but that doesn't work very well. A person with same problem, but a nicer shiny picture to attract you squirrels: So, it boils down to – DwmGetColorizationColor is completely unusable for applications attempting to apply the current color onto an opaque surface. i love this guy's screenshots much better than mine. Using his screenshots as a template, i made up a few more sparklies: For the last two screenshots, the alpha blended chip is a true partially transparent PNG, blending to your browser's background. Cool! (i'm such a geek) Edit 2: Had to arrange them in rainbow color. (i'm such a geek) Edit 3: Well now i of course have to add Yellow. Undocumented/Unsupported/Fragile Workarounds There is an undocumented export from DwmApi.dll at entry point 137, which we'll call DwmGetColorizationParameters: HRESULT GetColorizationParameters_Undocumented(out DWMCOLORIZATIONPARAMS params); struct DWMCOLORIZATIONPARAMS { public UInt32 ColorizationColor; public UInt32 ColorizationAfterglow; public UInt32 ColorizationColorBalance; public UInt32 ColorizationAfterglowBalance; public UInt32 ColorizationBlurBalance; public UInt32 ColorizationGlassReflectionIntensity; public UInt32 ColorizationOpaqueBlend; } We're interested in the first parameter: ColorizationColor. We can also read the value out of the registry: HKEY_CURRENT_USER\Software\Microsoft\Windows\DWM ColorizationColor: REG_DWORD = 0x6614A600 So you pick your poison of creating appcompat issues. You can rely on an undocumented API (which is bad, bad, bad, and can go away at any time) use an undocumented registry key (which is also bad, and can go away at any time) See also Is there a list of valid parameter combinations for GetThemeColor / Visual Styles API How does Windows change Aero Glass color? DWM - Colorization Color Handling Using DWMGetColorizationColor Retrieving Aero Glass base color for opaque surface rendering i've been wanting to ask this question for over a year now. i always knew that it's impossible to answer, and that the only way to get anyone to actually pay attention is to have colorful screenshots; developers are attracted to shiny things. But on the downside it means i had to put all kinds of work into making the lures.

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