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  • WPF - Overlapping Custom Tabs in a TabControl and ZIndex

    - by Rachel
    Problem I have a custom tab control using Chrome-shaped tabs that binds to a ViewModel. Because of the shape, the edges overlap a bit. I have a function that sets the tabItem's ZIndex on TabControl_SelectionChanged which works fine for selecting tabs, and dragging/dropping tabs, however when I Add or Close a tab via a Relay Command I am getting unusual results. Does anyone have any ideas? Default View http://i193.photobucket.com/albums/z197/Lady53461/tabs_default.jpg Removing Tabs http:/i193.photobucket.com/albums/z197/Lady53461/tabs_removing.jpg Adding 2 or more Tabs in a row http:/i193.photobucket.com/albums/z197/Lady53461/tabs_adding.jpg Code to set ZIndex private void PrimaryTabControl_SelectionChanged(object sender, SelectionChangedEventArgs e) { if (e.Source is TabControl) { TabControl tabControl = sender as TabControl; ItemContainerGenerator icg = tabControl.ItemContainerGenerator; if (icg.Status == System.Windows.Controls.Primitives.GeneratorStatus.ContainersGenerated) { foreach (object o in tabControl.Items) { UIElement tabItem = icg.ContainerFromItem(o) as UIElement; Panel.SetZIndex(tabItem, (o == tabControl.SelectedItem ? 100 : 90 - tabControl.Items.IndexOf(o))); } } } } By using breakpoints I can see that it is correctly setting the ZIndex to what I want it to, however the layout is not displaying the changes. I know some of the changes are in effect because if none of them were working then the tab edges would be reversed (the right tabs would be drawn on top of the left ones). Clicking a tab will correctly set the zindex of all tabs (including the one that should be drawn on top) and dragging/dropping them to rearrange them also renders correctly (which removes and reinserts the tab item). The only difference I can think of is I am using the MVVM design pattern and the buttons that Add/Close tabs are relay commands. Does anyone have any idea why this is happening and how I can fix it?? p.s. I did try setting a ZIndex in my ViewModel and binding to it, however the same thing happens when adding/removing tabs via the relay command. EDIT: Being a new user I couldn't post images and could only post 1 link. Images just show a picture of what the tags render as after each scenario. Adding more then 1 at a time will not reset the zindex of other recently-added tabs so they go behind the tab on the Right, and closing tabs does not correctly render the ZIndex of the SelectedTab that replaces it and it shows up behind the tab on its right.

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  • Need additional help with binding multiple CommandParameters using MultiBinding

    - by Dave
    I need to have a command handler for a ToggleButton that can take multiple parameters, namely the IsChecked property of said ToggleButton, along with a constant value, which could be a string, byte, int... doesn't matter. I found this great question on SO and followed the answer's link and read up on MultiBinding and IMultiValueConverter. It went really smoothly until I had to write the MultiBinding, when I realized that I also need to pass a constant value and couldn't do something like <Binding Value="1" /> I then came across another similar question that Kent Boogaart answered, and then I started to think about ways that I could get around this. One possible way is to not use MVVM and simply add the Tag property to my ToggleButton, in which case my MultiBinding would look like this: <MultiBinding Converter="{StaticResource MyConverter}"> <MultiBinding.Bindings> <Binding Path="IsChecked" /> <Binding Path="Tag" /> </MultiBinding.Bindings> </MultiBinding> Kent had made a comment along the lines of, "if you're using MVVM you should be able to get around this issue". However, I'm not sure that's an option for me, even though I have adopted MVVM as my WPF pattern of necessity choice. The reason why I say this is that I have wayyyy more than one ToggleButton in the UserControl, and each of the ToggleButtons' Commands need to call the same function. But since they are ToggleButtons, I can't use the property bound to IsChecked in the ViewModel, because I don't know which one was last clicked. I suppose I could add another private property to keep track of this, but it seems a little silly. As far as the constant goes, I could probably get rid of this if I did the tracking idea, but not sure of any other way to get around it. Does anyone have good suggestions for me here? :) EDIT -- ok, so I need to update my bindings, which still don't work quite right: <ToggleButton Tag="1" Command="{Binding MyCommand}" Style="{StaticResource PassFailToggleButtonStyle}" HorizontalContentAlignment="Center" Background="Transparent" BorderBrush="Transparent" BorderThickness="0"> <ToggleButton.CommandParameter> <MultiBinding Converter="{StaticResource MyConverter}"> <MultiBinding.Bindings> <Binding Path="IsChecked" RelativeSource="{RelativeSource Mode=Self}" /> <Binding Path="Tag" RelativeSource="{RelativeSource Mode=Self}" /> </MultiBinding.Bindings> </MultiBinding> </ToggleButton.CommandParameter> </ToggleButton> IsChecked was working, but not Tag. I just realized that Tag is a string... duh. It's working now! The key was to use a RelativeSource of Self.

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  • Rx Reactive extensions: Unit testing with FromAsyncPattern

    - by Andrew Anderson
    The Reactive Extensions have a sexy little hook to simplify calling async methods: var func = Observable.FromAsyncPattern<InType, OutType>( myWcfService.BeginDoStuff, myWcfService.EndDoStuff); func(inData).ObserveOnDispatcher().Subscribe(x => Foo(x)); I am using this in an WPF project, and it works great at runtime. Unfortunately, when trying to unit test methods that use this technique I am experiencing random failures. ~3 out of every five executions of a test that contain this code fails. Here is a sample test (implemented using a Rhino/unity auto-mocking container): [TestMethod()] public void SomeTest() { // arrange var container = GetAutoMockingContainer(); container.Resolve<IMyWcfServiceClient>() .Expect(x => x.BeginDoStuff(null, null, null)) .IgnoreArguments() .Do( new Func<Specification, AsyncCallback, object, IAsyncResult>((inData, asyncCallback, state) => { return new CompletedAsyncResult(asyncCallback, state); })); container.Resolve<IRepositoryServiceClient>() .Expect(x => x.EndRetrieveAttributeDefinitionsForSorting(null)) .IgnoreArguments() .Do( new Func<IAsyncResult, OutData>((ar) => { return someMockData; })); // act var target = CreateTestSubject(container); target.DoMethodThatInvokesService(); // Run the dispatcher for everything over background priority Dispatcher.CurrentDispatcher.Invoke(DispatcherPriority.Background, new Action(() => { })); // assert Assert.IsTrue(my operation ran as expected); } The problem that I see is that the code that I specified to run when the async action completed (in this case, Foo(x)), is never called. I can verify this by setting breakpoints in Foo and observing that they are never reached. Further, I can force a long delay after calling DoMethodThatInvokesService (which kicks off the async call), and the code is still never run. I do know that the lines of code invoking the Rx framework were called. Other things I've tried: I have attempted to modify the second last line according to the suggestions here: Reactive Extensions Rx - unit testing something with ObserveOnDispatcher No love. I have added .Take(1) to the Rx code as follows: func(inData).ObserveOnDispatcher().Take(1).Subscribe(x = Foo(x)); This improved my failure rate to something like 1 in 5, but they still occurred. I have rewritten the Rx code to use the plain jane Async pattern. This works, however my developer ego really would love to use Rx instead of boring old begin/end. In the end I do have a work around in hand (i.e. don't use Rx), however I feel that it is not ideal. If anyone has ran into this problem in the past and found a solution, I'd dearly love to hear it.

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  • Custom DataAnnotation attribute with datastore access in ASP.NET MVC 2

    - by mare
    I have my application designed with Repository pattern implemented and my code prepared for optional dependency injection in future, if we need to support another datastore. I want to create a custom validation attribute for my content objects. This attribute should perform some kind of datastore lookup. For instance, I need my content to have unique slugs. To check if a Slug already exist, I want to use custom DataAnnotation attribute in my Base content object (instead of manually checking if a slug exists each time in my controller's Insert actions). Attribute logic would do the validation. So far I have come up with this: public class UniqueSlugAttribute : ValidationAttribute { private readonly IContentRepository _repository; public UniqueSlugAttribute(ContentType contentType) { _repository = new XmlContentRepository(contentType); } public override bool IsValid(object value) { if (string.IsNullOrWhiteSpace(value.ToString())) { return false; } string slug = value.ToString(); if(_repository.IsUniqueSlug(slug)) return true; return false; } } part of my Base content class: ... [DataMember] public ContentType ContentType1 { get; set; } [DataMember] [Required(ErrorMessageResourceType = typeof (Localize), ErrorMessageResourceName = "Validation_SlugIsBlank")] [UniqueSlug(ContentType1)] public string Slug { get { return _slug; } set { if (!string.IsNullOrEmpty(value)) _slug = Utility.RemoveIllegalCharacters(value); } } ... There's an error in line [UniqueSlug(ContentType1)] saying: "An attribute argument must be a constant expression, typeof expression or array creation expression of an attribute parameter type." Let me explain that I need to provide the ContentType1 parameter to the Constructor of UniqueSlug class because I use it in my data provider. It is actually the same error that appears if you try do to this on the built-in Required attribute: [Required(ErrorMessageResourceType = typeof (Localize), ErrorMessageResourceName = Resources.Localize.SlugRequired] It does not allow us to set it to dynamic content. In the first case ContentType1 gets known at runtime, in the second case the Resources.Localize.SlugRequired also gets known at runtime (because the Culture settings are assigned at runtime). This is really annoying and makes so many things and implementation scenarios impossible. So, my first question is, how to get rid of this error? The second question I have, is whether you think that I should redesign my validation code in any way?

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  • Java ReentrantReadWriteLocks - how to safely acquire write lock?

    - by Andrzej Doyle
    I am using in my code at the moment a ReentrantReadWriteLock to synchronize access over a tree-like structure. This structure is large, and read by many threads at once with occasional modifications to small parts of it - so it seems to fit the read-write idiom well. I understand that with this particular class, one cannot elevate a read lock to a write lock, so as per the Javadocs one must release the read lock before obtaining the write lock. I've used this pattern successfully in non-reentrant contexts before. What I'm finding however is that I cannot reliably acquire the write lock without blocking forever. Since the read lock is reentrant and I am actually using it as such, the simple code lock.getReadLock().unlock(); lock.getWriteLock().lock() can block if I have acquired the readlock reentrantly. Each call to unlock just reduces the hold count, and the lock is only actually released when the hold count hits zero. EDIT to clarify this, as I don't think I explained it too well initially - I am aware that there is no built-in lock escalation in this class, and that I have to simply release the read lock and obtain the write lock. My problem is/was that regardless of what other threads are doing, calling getReadLock().unlock() may not actually release this thread's hold on the lock if it acquired it reentrantly, in which case the call to getWriteLock().lock() will block forever as this thread still has a hold on the read lock and thus blocks itself. For example, this code snippet will never reach the println statement, even when run singlethreaded with no other threads accessing the lock: final ReadWriteLock lock = new ReentrantReadWriteLock(); lock.getReadLock().lock(); // In real code we would go call other methods that end up calling back and // thus locking again lock.getReadLock().lock(); // Now we do some stuff and realise we need to write so try to escalate the // lock as per the Javadocs and the above description lock.getReadLock().unlock(); // Does not actually release the lock lock.getWriteLock().lock(); // Blocks as some thread (this one!) holds read lock System.out.println("Will never get here"); So I ask, is there a nice idiom to handle this situation? Specifically, when a thread that holds a read lock (possibly reentrantly) discovers that it needs to do some writing, and thus wants to "suspend" its own read lock in order to pick up the write lock (blocking as required on other threads to release their holds on the read lock), and then "pick up" its hold on the read lock in the same state afterwards? Since this ReadWriteLock implementation was specifically designed to be reentrant, surely there is some sensible way to elevate a read lock to a write lock when the locks may be acquired reentrantly? This is the critical part that means the naive approach does not work.

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  • Can Spring.Net function as PostSharp?

    - by Alex K
    A few months back I've discovered PostSharp, and for a time, it was good. But then legal came back with an answer saying that they don't like the licence of the old versions. Then the department told me that 2.0's price was unacceptably high (for the number of seats we need)... I was extremely disapponted, but not disheartened. Can't be the only such framework, I thought. I kept looking for a replacement, but most of it was either dead, ill maintained (especially in documentation department), for academic use, or all of the above (I'm looking at you Aspect.Net) Then I've discovered Spring.Net, and for a time, it was good. I've been reading the documentation and it went on to paint what seemed to be a supperior picture of an AOP nirvana. No longer was I locked to attributes to mark where I wanted code interception to take place, but it could be configured in XML and changes to it didn't require re-compile. Great. Then I looked at the samples and saw the following, in every single usage scenario: // Create AOP proxy using Spring.NET IoC container. IApplicationContext ctx = ContextRegistry.GetContext(); ICommand command = (ICommand)ctx["myServiceCommand"]; command.Execute(); if (command.IsUndoCapable) { command.UnExecute(); } Why must the first two lines of code exist? It ruins everything. This means I cannot simply provide a user with a set of aspects and attributes or XML configs that they can use by sticking appropriate attributes on the appropriate methods/classes/etc or editing the match pattern in XML. They have to modify their program logic to make this work! Is there a way to make Spring.Net behave as PostSharp in this case? (i.e. user only needs to add attributes/XML config, not edit content of any methods. Alternatively, is there a worthy and functioning alternative to PostSharp? I've seen a few question titled like this on SO, but none of them were actually looking to replace PostSharp, they only wanted to supplement its functionality. I need full replacement.

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  • Revisiting .NET, but what should I focus on?

    - by Wayne M
    After about a two-year hiatus, I'm brushing up on my .NET skills to find a .NET job (my previous two positions have very little development, or development using legacy technologies, so apart from a few very minor apps I have not touched .NET in close to two years). I'm aware of things like ASP.NET MVC, and I have previously read on things like NHibernate and DI/IOC, albeit I have yet to use them apart from very trivial "Hello World" type applications. I have a subscription to Rob Conery's Tekpub website and occasionally watch these videos when I have free time. My concern is this: I don't live in a very technical area. I would be surprised if any but the most tech-savvy companies have heard of, let alone use, ASP.NET MVC, NHibernate (or even LINQ/EF), or know about IoC. I would be willing to bet a large sum of money that 95% of the possible jobs I could obtain will use the following: Visual Source Safe, if any VCS at all ASP.NET 2.0 Webforms (3.5 if lucky) Raw ADO.NET on top of a very thin implementation of the Gateway pattern Stored Procedures in the database for most CRUD operations Gratuitous use of code-behind, with a Service layer if I'm lucky If I were extremely lucky, I might find a shop that has heard of ORMs and either uses one, or has wrote their own data abstraction. Also if I were lucky, the company would be using Model-View-Presenter. In light of this I'm not sure what I should focus on learning. Personally, I would prefer to be using the latest stuff - ASP.NET MVC, NHibernate, jQuery, WCF etc. Reality says I should go back to the basics, since it looks like most potential opportunities aren't going to be anywhere near the cutting edge, or anywhere close to it. And, as much as I would like to find a position and start to show the other developers the benefits, in my past experience this has usually resulted in my being fired for "not being a team player" and doing things the bad old way. So, I am curious how you would approach a situation like this? What should I focus on, in order to A) Reaquaint myself with .NET, and B) Prepare myself to obtain a .NET job again that is more than likely going to use techniques that I and most other knowledgeable developers will scoff at?

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  • Validate a string in a table in SQL Server - CLR function or T-SQL

    - by Ashish Gupta
    I need to check If a column value (string) in SQL server table starts with a small letter and can only contain '_', '-', numbers and alphabets. I know I can use a SQL server CLR function for that. However, I am trying to implement that validation using a scalar UDF and could make very little here...I can use 'NOT LIKE', but I am not sure how to make sure I validate the string irrespective of the order of characters or in other words write a pattern in SQL for this. Am I better off using a SQL CLR function? Any help will be appreciated.. Thanks in advance Thank you everyone for their comments. This morning, I chose to go CLR function way. For the purpose of what I was trying to achieve, I created one CLR function which does the validation of an input string and have that called from a SQL UDF and It works well. Just to measure the performance of t-SQL UDF using SQL CLR function vs t- SQL UDF, I created a SQL CLR function which will just check if the input string contains only small letters, it should return true else false and have that called from a UDF (IsLowerCaseCLR). After that I also created a regular t-SQL UDF(IsLowerCaseTSQL) which does the same thing using the 'NOT LIKE'. Then I created a table (Person) with columns Name(varchar) and IsValid(bit) columns and populate that with names to test. Data :- 1000 records with 'Ashish' as value for Name column 1000 records with 'ashish' as value for Name column then I ran the following :- UPDATE Person Set IsValid=1 WHERE dbo.IsLowerCaseTSQL (Name) Above updated 1000 records (with Isvalid=1) and took less than a second. I deleted all the data in the table and repopulated the same with same data. Then updated the same table using Sql CLR UDF (with Isvalid=1) and this took 3 seconds! If update happens for 5000 records, regular UDF takes 0 seconds compared to CLR UDF which takes 16 seconds! I am very less knowledgeable on t-SQL regular expression or I could have tested my actual more complex validation criteria. But I just wanted to know, even I could have written that, would that have been faster than the SQL CLR function considering the example above. Are we using SQL CLR because we can implement we can implement lot richer logic which would have been difficult otherwise If we write in regular SQL. Sorry for this long post. I just want to know from the experts. Please feel free to ask if you could not understand anything here. Thank you again for your time.

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  • Hooking DirectX EndScene from an injected DLL

    - by Etan
    I want to detour EndScene from an arbitrary DirectX 9 application to create a small overlay. As an example, you could take the frame counter overlay of FRAPS, which is shown in games when activated. I know the following methods to do this: Creating a new d3d9.dll, which is then copied to the games path. Since the current folder is searched first, before going to system32 etc., my modified DLL gets loaded, executing my additional code. Downside: You have to put it there before you start the game. Same as the first method, but replacing the DLL in system32 directly. Downside: You cannot add game specific code. You cannot exclude applications where you don't want your DLL to be loaded. Getting the EndScene offset directly from the DLL using tools like IDA Pro 4.9 Free. Since the DLL gets loaded as is, you can just add this offset to the DLL starting address, when it is mapped to the game, to get the actual offset, and then hook it. Downside: The offset is not the same on every system. Hooking Direct3DCreate9 to get the D3D9, then hooking D3D9-CreateDevice to get the device pointer, and then hooking Device-EndScene through the virtual table. Downside: The DLL cannot be injected, when the process is already running. You have to start the process with the CREATE_SUSPENDED flag to hook the initial Direct3DCreate9. Creating a new Device in a new window, as soon as the DLL gets injected. Then, getting the EndScene offset from this device and hooking it, resulting in a hook for the device which is used by the game. Downside: as of some information I have read, creating a second device may interfere with the existing device, and it may bug with windowed vs. fullscreen mode etc. Same as the third method. However, you'll do a pattern scan to get EndScene. Downside: doesn't look that reliable. How can I hook EndScene from an injected DLL, which may be loaded when the game is already running, without having to deal with different d3d9.dll's on other systems, and with a method which is reliable? How does FRAPS for example perform it's DirectX hooks? The DLL should not apply to all games, just to specific processes where I inject it via CreateRemoteThread.

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  • Synchronization requirements for FileStream.(Begin/End)(Read/Write)

    - by Doug McClean
    Is the following pattern of multi-threaded calls acceptable to a .Net FileStream? Several threads calling a method like this: ulong offset = whatever; // different for each thread byte[] buffer = new byte[8192]; object state = someState; // unique for each call, hence also for each thread lock(theFile) { theFile.Seek(whatever, SeekOrigin.Begin); IAsyncResult result = theFile.BeginRead(buffer, 0, 8192, AcceptResults, state); } if(result.CompletedSynchronously) { // is it required for us to call AcceptResults ourselves in this case? // or did BeginRead already call it for us, on this thread or another? } Where AcceptResults is: void AcceptResults(IAsyncResult result) { lock(theFile) { int bytesRead = theFile.EndRead(result); // if we guarantee that the offset of the original call was at least 8192 bytes from // the end of the file, and thus all 8192 bytes exist, can the FileStream read still // actually read fewer bytes than that? // either: if(bytesRead != 8192) { Panic("Page read borked"); } // or: // issue a new call to begin read, moving the offsets into the FileStream and // the buffer, and decreasing the requested size of the read to whatever remains of the buffer } } I'm confused because the documentation seems unclear to me. For example, the FileStream class says: Any public static members of this type are thread safe. Any instance members are not guaranteed to be thread safe. But the documentation for BeginRead seems to contemplate having multiple read requests in flight: Multiple simultaneous asynchronous requests render the request completion order uncertain. Are multiple reads permitted to be in flight or not? Writes? Is this the appropriate way to secure the location of the Position of the stream between the call to Seek and the call to BeginRead? Or does that lock need to be held all the way to EndRead, hence only one read or write in flight at a time? I understand that the callback will occur on a different thread, and my handling of state, buffer handle that in a way that would permit multiple in flight reads. Further, does anyone know where in the documentation to find the answers to these questions? Or an article written by someone in the know? I've been searching and can't find anything. Relevant documentation: FileStream class Seek method BeginRead method EndRead IAsyncResult interface

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  • Entity Attribute Value Database vs. strict Relational Model Ecommerce question

    - by Dr. Zim
    It is safe to say that the EAV/CR database model is bad. That said, Question: What database model, technique, or pattern should be used to deal with "classes" of attributes describing e-commerce products which can be changed at run time? In a good E-commerce database, you will store classes of options (like TV resolution then have a resolution for each TV, but the next product may not be a TV and not have "TV resolution"). How do you store them, search efficiently, and allow your users to setup product types with variable fields describing their products? If the search engine finds that customers typically search for TVs based on console depth, you could add console depth to your fields, then add a single depth for each tv product type at run time. There is a nice common feature among good e-commerce apps where they show a set of products, then have "drill down" side menus where you can see "TV Resolution" as a header, and the top five most common TV Resolutions for the found set. You click one and it only shows TVs of that resolution, allowing you to further drill down by selecting other categories on the side menu. These options would be the dynamic product attributes added at run time. Further discussion: So long story short, are there any links out on the Internet or model descriptions that could "academically" fix the following setup? I thank Noel Kennedy for suggesting a category table, but the need may be greater than that. I describe it a different way below, trying to highlight the significance. I may need a viewpoint correction to solve the problem, or I may need to go deeper in to the EAV/CR. Love the positive response to the EAV/CR model. My fellow developers all say what Jeffrey Kemp touched on below: "new entities must be modeled and designed by a professional" (taken out of context, read his response below). The problem is: entities add and remove attributes weekly (search keywords dictate future attributes) new entities arrive weekly (products are assembled from parts) old entities go away weekly (archived, less popular, seasonal) The customer wants to add attributes to the products for two reasons: department / keyword search / comparison chart between like products consumer product configuration before checkout The attributes must have significance, not just a keyword search. If they want to compare all cakes that have a "whipped cream frosting", they can click cakes, click birthday theme, click whipped cream frosting, then check all cakes that are interesting knowing they all have whipped cream frosting. This is not specific to cakes, just an example.

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  • How to arrange models, views, controllers in a Kohana 3 project

    - by Pekka
    I'm looking at how to set up a mid-sized web application with Kohana 3. I have implemented MVC patterns in the past but never worked against a "formalized" MVC framework so I'm still getting my head around the terminology - toying around with basic examples, building views and templates, and so on. I'm progressing fairly well but I want to set up a real-world web project (one of my own that I've been planning for quite some time now) as a learning object. I learn best by example, but example-based documentation is a bit sparse for Kohana 3 right now - they say so themselves on the site. While I'm not worried about getting into the framework soon enough, I'm a bit concerned about arranging a healthily structured code base from the start - i.e. how to split up controllers, how to name them, and how to separate the functionality into the appropriate models. My application could, in its core, be described as a business directory with a main businesses table. Businesses can be listed by category and by street name. Each business has a detail page. Business owners can log in and edit their business's entry. Businesses can post offers into an offers table. I know this is not very detailed, but I don't want to cram too much information into this question. I'll be more than happy to go into more detail if needed. Supposing I have all the basic functionality worked out and in place already - list all businesses, edit business, list businesses by street name, create offer logged in as business, and so on, and I'm just looking for how to fit the functionality into a MVC pattern and into a Kohana application structure that can be easily extended: Do you know real-life, publicly accessible examples of "database-heavy" applications like directories, online communities... with a log-in area built on Kohana 3 where I could take a peek how they do it? Are there conventions or best practices on how to structure an extendable login area for end users in a Kohana project that is not only able to handle a business directory page, but further products on separate pages as well? Do you know application structuring HOWTOs or best practices for Kohana 3 not mentioned in the user guide and the inofficial Wiki? Have you built something similar and could give me some recommendations?

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  • Defining InputBindings within a Style

    - by Brent
    I'm creating a WPF app using the MVVM design pattern, and I'm trying to extend the TabItem control so that it closes the tab when the user clicks the middle mouse button. I'm trying to achieve this using InputBindings, and it works very well until I try to define it within a style. I've learned that you cannot add InputBindings to a style unless you attach it using a DependencyProperty. So I followed this similar post here... and it works... almost. I can close one tab using the middle mouse button, but it won't work on any of the other tabs (all of the tabs are added at runtime and inherit the same style). So I need some help. Why would this only be working the first time, and not after? Obviously I could create a custom control that inherits from a TabItem and make it work, but I'd like to figure this out as I can see this being expanded in my projects. I'm no expert on DependencyProperties, so please help me out. Thanks! Style: <Style TargetType="{x:Type TabItem}"> <Setter Property="w:Attach.InputBindings"> <Setter.Value> <InputBindingCollection> <MouseBinding MouseAction="MiddleClick" Command="{Binding CloseCommand}"/> </InputBindingCollection> </Setter.Value> </Setter> ... </Style> Class public class Attach { public static readonly DependencyProperty InputBindingsProperty = DependencyProperty.RegisterAttached("InputBindings", typeof(InputBindingCollection), typeof(Attach), new FrameworkPropertyMetadata(new InputBindingCollection(), (sender, e) => { var element = sender as UIElement; if (element == null) return; element.InputBindings.Clear(); element.InputBindings.AddRange((InputBindingCollection)e.NewValue); })); public static InputBindingCollection GetInputBindings(UIElement element) { return (InputBindingCollection)element.GetValue(InputBindingsProperty); } public static void SetInputBindings(UIElement element, InputBindingCollection inputBindings) { element.SetValue(InputBindingsProperty, inputBindings); } }

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  • Rails - embedded polymorphic comment list + add comment form - example?

    - by odigity
    Hey, all. Working on my first Rails app. I've searched all around - read a bunch of tutorials, articles, and forum posts, watched some screencasts, and I've found a few examples that come close to what I'm trying to do (notably http://railscasts.com/episodes/154-polymorphic-association and ep 196 about nested model forms), but not exactly. I have two models (Podcast and BlogPost) that need to be commentable, and I have a Comment model that is polymorphically related to both. The railscasts above had a very similar example (ep 154), but Ryan used a full set of nested routes, so there were specific templates for adding and editing comments. What I want to do is show the list of comments right on the Podcast or BlogPost page, along with an Add Comment form at the bottom. I don't need a separate add template/route, and I don't need the ability to edit, only delete. This is a pretty common design on the web, but I can't find a Rails example specifically about this pattern. Here's my current understanding: I need routes for the create and delete actions, of course, but there are no templates associated with those. I'm also guessing that the right approach is to create a partial that can be included at the bottom of both the Podcast and BlogPost show template. The logical name for the partial seems to me to be something like _comments.html.haml. I know it's a common convention to have the object passed to the partial be named after the template, but calling the object 'comments' seems to not match my use case, since what I really need to pass is the commentable object (Podcast or BlogPost). So, I guess I'd use the locals option for the render partial call? (:commentable = @podcast). Inside the partial, I could call commentable.comments to get the comments collection, render that with a second partial (this time with the conventional use case, calling the partial _comment.html.haml), then create a form that submits to... what? REST-wise, it should be a POST to the collection, which would be /podcast|blogpost/:id/comments, and I think the helper for that is podcast_comments_path(podcast) if it were a podcast - not sure what to do though, since I'm using polymorphic comments. That would trigger the Comment.create action, which would then need to redirect back to the podcast|blogpost path /podcast|blogpost/:id. It's all a bit overwhelming, which is why I was really hoping to find a screencast or example that specifically implements this design.

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  • Best practices concerning view model and model updates with a subset of the fields

    - by Martin
    By picking MVC for developing our new site, I find myself in the midst of "best practices" being developed around me in apparent real time. Two weeks ago, NerdDinner was my guide but with the development of MVC 2, even it seems outdated. It's an thrilling experience and I feel privileged to be in close contact with intelligent programmers daily. Right now I've stumbled upon an issue I can't seem to get a straight answer on - from all the blogs anyway - and I'd like to get some insight from the community. It's about Editing (read: Edit action). The bulk of material out there, tutorials and blogs, deal with creating and view the model. So while this question may not spell out a question, I hope to get some discussion going, contributing to my decision about the path of development I'm to take. My model represents a user with several fields like name, address and email. All the names, in fact, on field each for first name, last name and middle name. The Details view displays all these fields but you can change only one set of fields at a time, for instance, your names. The user expands a form while the other fields are still visible above and below. So the form that is posted back contains a subset of the fields representing the model. While this is appealing to us and our layout concerns, for various reasons, it is to be shunned by serious MVC-developers. I've been reading about some patterns and best practices and it seems that this is not in key with the paradigm of viewmodel == view. Or have I got it wrong? Anyway, NerdDinner dictates using FormCollection och UpdateModel. All the null fields are happily ignored. Since then, the MVC-community has abandoned this approach to such a degree that a bug in MVC 2 was not discovered. UpdateModel does not work without a complete model in your formcollection. The view model pattern receiving most praise seems to be Dedicated view model that contains a custom view model entity and is the only one that my design issue could be made compatible with. It entails a tedious amount of mapping, albeit lightened by the use of AutoMapper and the ideas of Jimmy Bogard, that may or may not be worthwhile. He also proposes a 1:1 relationship between view and view model. In keeping with these design paradigms, I am to create a view and associated view for each of my expanding sets of fields. The view models would each be nearly identical, differing only in the fields which are read-only, the views also containing much repeated markup. This seems absurd to me. In future I may want to be able to display two, more or all sets of fields open simultaneously. I will most attentively read the discussion I hope to spark. Many thanks in advance.

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  • Arranging models, views, controllers in a Kohana 3 project

    - by Pekka
    I'm looking at how to set up a mid-sized web application with Kohana 3. I have implemented MVC patterns in the past but never worked against a "formalized" MVC framework so I'm still getting my head around the terminology - toying around with basic examples, building views and templates, and so on. I'm progressing fairly well but I want to set up a real-world web project (one of my own that I've been planning for quite some time now) as a learning object. I learn best by example, but example-based documentation is a bit sparse for Kohana 3 right now - they say so themselves on the site. While I'm not worried about getting into the framework soon enough, I'm a bit concerned about arranging a healthily structured code base from the start - i.e. how to split up controllers, how to name them, and how to separate the functionality into the appropriate models. My application could, in its core, be described as a business directory with a main businesses table. Businesses can be listed by category and by street name. Each business has a detail page. Business owners can log in and edit their business's entry. Businesses can post offers into an offers table. I know this is pretty vague, but I don't want to cram too much information into this question. I'll be more than happy to go into more detail if needed. Supposing I have all the basic functionality worked out and in place already - list all businesses, edit business, list businesses by street name, create offer, and so on, and I'm just looking for how to fit the functionality into a MVC pattern and into a Kohana application structure that can be easily extended: Do you know real-life, publicly accessible examples of "database-heavy" applications like directories, online communities... with a log-in area built on Kohana 3 where I could take a peek how they do it? Are there conventions or best practices on how to structure an extendable login area for end users in a Kohana project that is not only able to handle a business directory page, but further products on separate pages as well? Do you know application structuring HOWTOs or best practices for Kohana 3 not mentioned in the user guide and the inofficial Wiki? Have you built something similar and could give me some recommendations?

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  • Implement looped movement animation with tap to cancel

    - by Nader
    Hi All; My app is based around a grid and an image that moves within a grid that is contained within a scrollview. I have an imageview that I am animating from one cell to another in time with a slow finger movement and recentering the scrollview. That is rather straight forward. I have also implement the ability to detect a swipe and therefore move the image all the way to the end of the grid and the uiscrollview recentering. I have even implemented the ability to detect a subsequent tap and freeze the swiped movement. The issue with the swipe movement is that the UIScrollView will scroll all the way to the end before the Image reaches the end and so I have to wait for the image to arrive. Also, when I freeze the movement of the image, I have to re-align the image to a cell (which I can do). I have come to the realization that I have to animate the image one cell at a time for swipes and recentering the uiscrollview before moving the image to the next cell. I have attempted to implement this but I cannot come up with a solution that works or works properly. Can anyone suggest how I go about implementing this? Even if you are able to put up code from a different example or sudo code, it would help a lot as I cannot workout how this should be done, should I be using selectors, a listener in delegates, I just simply lack the experience to solve this design pattern. Here is some code: Note that the sprite is an UIImageView - (void)animateViewToPosition:(SpriteView *)sprite Position:(CGPoint)pos Duration:(CFTimeInterval)duration{ CGMutablePathRef traversePath = CGPathCreateMutable(); CGPathMoveToPoint(traversePath, NULL, sprite.center.x, sprite.center.y); CGPathAddLineToPoint(traversePath, NULL, pos.x, pos.y); CAKeyframeAnimation *traverseAnimation = [CAKeyframeAnimation animationWithKeyPath:kAnimatePosition]; traverseAnimation.duration = duration; traverseAnimation.removedOnCompletion = YES; traverseAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear]; traverseAnimation.delegate = sprite; traverseAnimation.path = traversePath; CGPathRelease(traversePath); [sprite.layer addAnimation:traverseAnimation forKey:kAnimatePosition]; sprite.center = pos;

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  • Implement looped movement animation with tap to cancel

    - by Nader
    Hi All; My app is based around a grid and an image that moves within a grid that is contained within a scrollview. I have an imageview that I am animating from one cell to another in time with a slow finger movement and recentering the scrollview. That is rather straight forward. I have also implement the ability to detect a swipe and therefore move the image all the way to the end of the grid and the uiscrollview recentering. I have even implemented the ability to detect a subsequent tap and freeze the swiped movement. The issue with the swipe movement is that the UIScrollView will scroll all the way to the end before the Image reaches the end and so I have to wait for the image to arrive. Also, when I freeze the movement of the image, I have to re-align the image to a cell (which I can do). I have come to the realization that I have to animate the image one cell at a time for swipes and recentering the uiscrollview before moving the image to the next cell. I have attempted to implement this but I cannot come up with a solution that works or works properly. Can anyone suggest how I go about implementing this? Even if you are able to put up code from a different example or sudo code, it would help a lot as I cannot workout how this should be done, should I be using selectors, a listener in delegates, I just simply lack the experience to solve this design pattern. Here is some code: Note that the sprite is an UIImageView - (void)animateViewToPosition:(SpriteView *)sprite Position:(CGPoint)pos Duration:(CFTimeInterval)duration{ CGMutablePathRef traversePath = CGPathCreateMutable(); CGPathMoveToPoint(traversePath, NULL, sprite.center.x, sprite.center.y); CGPathAddLineToPoint(traversePath, NULL, pos.x, pos.y); CAKeyframeAnimation *traverseAnimation = [CAKeyframeAnimation animationWithKeyPath:kAnimatePosition]; traverseAnimation.duration = duration; traverseAnimation.removedOnCompletion = YES; traverseAnimation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionLinear]; traverseAnimation.delegate = sprite; traverseAnimation.path = traversePath; CGPathRelease(traversePath); [sprite.layer addAnimation:traverseAnimation forKey:kAnimatePosition]; sprite.center = pos; }

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  • Haskell: how to get through 'no instance for' ?

    - by artemave
    I am learning Haskell. I am on the 8th chapter of this book. The main thing I've learned so far is that Haskell is very unfriendly to me and it bites my ass where possible. Moreover... Heck! Enough mourning, to business. Here is the code: module GlobRegex ( globToRegex, matchesGlob ) where import Text.Regex.Posix import Text.Regex.Posix.String import Text.Regex.Base.RegexLike data CaseOpt = Case | NoCase deriving (Eq) matchesGlob :: String -> String -> CaseOpt -> Bool matchesGlob name pat caseopt = match regex name where regex = case caseopt of NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex pat) Case -> makeRegex (globToRegex pat) globToRegex :: String -> String ... And here is how it fails to compile: Prelude Text.Regex.Posix Text.Regex.Base.RegexLike> :load globtoregex\GlobRegex. hs [1 of 1] Compiling GlobRegex ( globtoregex\GlobRegex.hs, interpreted ) globtoregex\GlobRegex.hs:14:31: No instance for (RegexLike regex [Char]) arising from a use of `match' at globtoregex\GlobRegex.hs:14:31-46 Possible fix: add an instance declaration for (RegexLike regex [Char]) In the expression: match regex name In the definition of `matchesGlob': matchesGlob name pat caseopt = match regex name where regex = case caseopt of { NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex pat) Case -> makeRegex (globToRegex pat) } globtoregex\GlobRegex.hs:17:23: No instance for (RegexMaker regex CompOption execOpt String) arising from a use of `makeRegex' at globtoregex\GlobRegex.hs:17:23-49 Possible fix: add an instance declaration for (RegexMaker regex CompOption execOpt String) In the expression: makeRegex (globToRegex pat) In a case alternative: Case -> makeRegex (globToRegex pat) In the expression: case caseopt of { NoCase -> makeRegexOpts (defaultCompOpt + compIgnoreCase) defaultExecOpt (globToRegex p at) Case -> makeRegex (globToRegex pat) } Failed, modules loaded: none. To my best understanding, Text.Regex.Posix.String provides instances for RegexLike Regex String and RegexMaker Regex CompOption ExecOption String, so it should work. On the other hand, I can see that regex in the error message is type variable, not a concrete type, so, perhaps not... Anyway, this is where I am stuck. May be there is a common pattern for resolving no instance for type of problems? Or, in Haskell terms, instance of SmartGuess typeclass for no instance for?

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  • My block is not retaining some of its objects

    - by Drew Crawford
    From the Blocks documentation: In a reference-counted environment, by default when you reference an Objective-C object within a block, it is retained. This is true even if you simply reference an instance variable of the object. I am trying to implement a completion handler pattern, where a block is given to an object before the work is performed and the block is executed by the receiver after the work is performed. Since I am being a good memory citizen, the block should own the objects it references in the completion handler and then they will be released when the block goes out of scope. I know enough to know that I must copy the block to move it to the heap since the block will survive the stack scope in which it was declared. However, one of my objects is getting deallocated unexpectedly. After some playing around, it appears that certain objects are not retained when the block is copied to the heap, while other objects are. I am not sure what I am doing wrong. Here's the smallest test case I can produce: typedef void (^ActionBlock)(UIView*); In the scope of some method: NSObject *o = [[[NSObject alloc] init] autorelease]; mailViewController = [[[MFMailComposeViewController alloc] init] autorelease]; NSLog(@"o's retain count is %d",[o retainCount]); NSLog(@"mailViewController's retain count is %d",[mailViewController retainCount]); ActionBlock myBlock = ^(UIView *view) { [mailViewController setCcRecipients:[NSArray arrayWithObjects:@"[email protected]",nil]]; [o class]; }; NSLog(@"mailViewController's retain count after the block is %d",[mailViewController retainCount]); NSLog(@"o's retain count after the block is %d",[o retainCount]); Block_copy(myBlock); NSLog(@"o's retain count after the copy is %d",[o retainCount]); NSLog(@"mailViewController's retain count after the copy is %d",[mailViewController retainCount]); I expect both objects to be retained by the block at some point, and I certainly expect their retain counts to be identical. Instead, I get this output: o's retain count is 1 mailViewController's retain count is 1 mailViewController's retain count after the block is 1 o's retain count after the block is 1 o's retain count after the copy is 2 mailViewController's retain count after the copy is 1 o (subclass of NSObject) is getting retained properly and will not go out of scope. However mailViewController is not retained and will be deallocated before the block is run, causing a crash.

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  • Validate a string in a table in SQL Server - CLR function or T-SQL (Question updated)

    - by Ashish Gupta
    I need to check If a column value (string) in SQL server table starts with a small letter and can only contain '_', '-', numbers and alphabets. I know I can use a SQL server CLR function for that. However, I am trying to implement that validation using a scalar UDF and could make very little here...I can use 'NOT LIKE', but I am not sure how to make sure I validate the string irrespective of the order of characters or in other words write a pattern in SQL for this. Am I better off using a SQL CLR function? Any help will be appreciated.. Thanks in advance Thank you everyone for their comments. This morning, I chose to go CLR function way. For the purpose of what I was trying to achieve, I created one CLR function which does the validation of an input string and have that called from a SQL UDF and It works well. Just to measure the performance of t-SQL UDF using SQL CLR function vs t- SQL UDF, I created a SQL CLR function which will just check if the input string contains only small letters, it should return true else false and have that called from a UDF (IsLowerCaseCLR). After that I also created a regular t-SQL UDF(IsLowerCaseTSQL) which does the same thing using the 'NOT LIKE'. Then I created a table (Person) with columns Name(varchar) and IsValid(bit) columns and populate that with names to test. Data :- 1000 records with 'Ashish' as value for Name column 1000 records with 'ashish' as value for Name column then I ran the following :- UPDATE Person Set IsValid=1 WHERE dbo.IsLowerCaseTSQL (Name) Above updated 1000 records (with Isvalid=1) and took less than a second. I deleted all the data in the table and repopulated the same with same data. Then updated the same table using Sql CLR UDF (with Isvalid=1) and this took 3 seconds! If update happens for 5000 records, regular UDF takes 0 seconds compared to CLR UDF which takes 16 seconds! I am very less knowledgeable on t-SQL regular expression or I could have tested my actual more complex validation criteria. But I just wanted to know, even I could have written that, would that have been faster than the SQL CLR function considering the example above. Are we using SQL CLR because we can implement we can implement lot richer logic which would have been difficult otherwise If we write in regular SQL. Sorry for this long post. I just want to know from the experts. Please feel free to ask if you could not understand anything here. Thank you again for your time.

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  • Regex slow on Windows Server 2008

    - by pjmyburg
    Hi I have a situation where my regular expressions compile extremely slowly on Windows Server 2008. I wrote a small console application to highlight this issue. The app generates its own input and builds up a Regex from words in an XML file. I built a release version of this app and ran it both on my personal laptop (running XP) and the Windows 2008 server. The regular expression took 0.21 seconds to compile on my laptop, but 23 seconds to compile on the server. Any ideas what could be causing this? The problem is only on first use of the Regex (when it is first compiled - thereafter it is fine) I have also found another problem - when using \s+ in the regular expression on the same Windows 2008 server, the memory balloons (uses 4GB+) and the compilation of the Regex never finishes. Is there a known issue with Regex and 64 bit .net? Is there a fix/patch available for this? I cannot really find any info on the net, but I have found a few articles about this same issues in Framework 2.0 - surely this has been fixed by now? More info: The server is running the 64 bit version of the .net framework (3.5 SP1) and on my laptop I have Visual Studio 2008 and the 3.5 framework installed. The regular expression is of the following pattern: ^word$|^word$|^word$ and is constructed with the following flags: RegexOptions.IgnoreCase | RegexOptions.Compiled Edit: Here is a code snippet: StringBuilder regexString = new StringBuilder(); if (!String.IsNullOrEmpty(fileLocation)) { XmlTextReader textReader = new XmlTextReader(fileLocation); textReader.Read(); while (textReader.Read()) { textReader.MoveToElement(); if (textReader.Name == "word") { regexString.Append("^" + textReader.GetAttribute(0) + "$|"); } } ProfanityFilter = new Regex(regexString.ToString(0, regexString.Length - 1), RegexOptions.IgnoreCase | RegexOptions.Compiled); } DateTime time = DateTime.Now; Console.WriteLine("\nIsProfane:\n" + ProfanityFilter.IsMatch("test")); Console.WriteLine("\nTime: " + (DateTime.Now - time).TotalSeconds); Console.ReadKey(); This results in a time of 0.21 seconds on my laptop and 23 seconds on the 2008 server. The XML file consists of 168 words in the following format: <word text="test" />

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  • RegEx strip html tags problem

    - by Aleksandar Mirilovic
    Hi, I've tried to strip html tags using regex replace with pattern "<[^]*" from word generated html that looks like this: <html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40"> <head> <meta http-equiv=Content-Type content="text/html; charset=iso-8859-2"> <meta name=Generator content="Microsoft Word 11 (filtered medium)"> <!--[if !mso]> <style> v\:* {behavior:url(#default#VML);} o\:* {behavior:url(#default#VML);} w\:* {behavior:url(#default#VML);} .shape {behavior:url(#default#VML);} </style> <![endif]--><o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="place" downloadurl="http://www.5iantlavalamp.com/"/> <!--[if !mso]> <style> st1\:*{behavior:url(#default#ieooui) } </style> <![endif]--> <style> <!-- /* Font Definitions / @font-face {font-family:Tahoma; panose-1:2 11 6 4 3 5 4 4 2 4;} / Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {margin:0in; margin-bottom:.0001pt; font-size:12.0pt; font-family:"Times New Roman";} a:link, span.MsoHyperlink {color:blue; text-decoration:underline;} a:visited, span.MsoHyperlinkFollowed {color:purple; text-decoration:underline;} span.EmailStyle17 {mso-style-type:personal; font-family:Arial; color:windowtext;} span.EmailStyle18 {mso-style-type:personal-reply; font-family:Arial; color:navy;} @page Section1 {size:8.5in 11.0in; margin:1.0in 1.25in 1.0in 1.25in;} div.Section1 {page:Section1;} --> </style> </head> Everything works fine except for the bolded lines above, anybody got ideas how to match the them to? Thanks, Aleksandar

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  • Succinct introduction to C++/CLI for C#/Haskell/F#/JS/C++/... programmer

    - by Henrik
    Hello everybody, I'm trying to write integrations with the operating system and with things like active directory and Ocropus. I know a bunch of programming languages, including those listed in the title. I'm trying to learn exactly how C++/CLI works, but can't find succinct, exact and accurate descriptions online from the searching that I have done. So I ask here. Could you tell me the pitfalls and features of C++/CLI? Assume I know all of C# and start from there. I'm not an expert in C++, so some of my questions' answers might be "just like C++", but could say that I am at C#. I would like to know things like: Converting C++ pointers to CLI pointers, Any differences in passing by value/doubly indirect pointers/CLI pointers from C#/C++ and what is 'recommended'. How do gcnew, __gc, __nogc work with Polymorphism Structs Inner classes Interfaces The "fixed" keyword; does that exist? Compiling DLLs loaded into the kernel with C++/CLI possible? Loaded as device drivers? Invoked by the kernel? What does this mean anyway (i.e. to load something into the kernel exactly; how do I know if it is?)? L"my string" versus "my string"? wchar_t? How many types of chars are there? Are we safe in treating chars as uint32s or what should one treat them as to guarantee language indifference in code? Finalizers (~ClassName() {}) are discouraged in C# because there are no garantuees they will run deterministically, but since in C++ I have to use "delete" or use copy-c'tors as to stack allocate memory, what are the recommendations between C#/C++ interactions? What are the pitfalls when using reflection in C++/CLI? How well does C++/CLI work with the IDisposable pattern and with SafeHandle, SafeHandleZeroOrMinusOneIsInvalid? I've read briefly about asynchronous exceptions when doing DMA-operations, what are these? Are there limitations you impose upon yourself when using C++ with CLI integration rather than just doing plain C++? Attributes in C++ similar to Attributes in C#? Can I use the full meta-programming patterns available in C++ through templates now and still have it compile like ordinary C++? Have you tried writing C++/CLI with boost? What are the optimal ways of interfacing the boost library with C++/CLI; can you give me an example of passing a lambda expression to an iterator/foldr function? What is the preferred way of exception handling? Can C++/CLI catch managed exceptions now? How well does dynamic IL generation work with C++/CLI? Does it run on Mono? Any other things I ought to know about?

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  • Succinct introduction to C++/CLI for C#/Haskell/F#/JS/C++/... programmer

    - by Henrik
    Hello everybody, I'm trying to write integrations with the operating system and with things like active directory and Ocropus. I know a bunch of programming languages, including those listed in the title. I'm trying to learn exactly how C++/CLI works, but can't find succinct, exact and accurate descriptions online from the searching that I have done. So I ask here. Could you tell me the pitfalls and features of C++/CLI? Assume I know all of C# and start from there. I'm not an expert in C++, so some of my questions' answers might be "just like C++", but could say that I am at C#. I would like to know things like: Converting C++ pointers to CLI pointers, Any differences in passing by value/doubly indirect pointers/CLI pointers from C#/C++ and what is 'recommended'. How do gcnew, __gc, __nogc work with Polymorphism Structs Inner classes Interfaces The "fixed" keyword; does that exist? Compiling DLLs loaded into the kernel with C++/CLI possible? Loaded as device drivers? Invoked by the kernel? What does this mean anyway (i.e. to load something into the kernel exactly; how do I know if it is?)? L"my string" versus "my string"? wchar_t? How many types of chars are there? Are we safe in treating chars as uint32s or what should one treat them as to guarantee language indifference in code? Finalizers (~ClassName() {}) are discouraged in C# because there are no garantuees they will run deterministically, but since in C++ I have to use "delete" or use copy-c'tors as to stack allocate memory, what are the recommendations between C#/C++ interactions? What are the pitfalls when using reflection in C++/CLI? How well does C++/CLI work with the IDisposable pattern and with SafeHandle, SafeHandleZeroOrMinusOneIsInvalid? I've read briefly about asynchronous exceptions when doing DMA-operations, what are these? Are there limitations you impose upon yourself when using C++ with CLI integration rather than just doing plain C++? Attributes in C++ similar to Attributes in C#? Can I use the full meta-programming patterns available in C++ through templates now and still have it compile like ordinary C++? Have you tried writing C++/CLI with boost? What are the optimal ways of interfacing the boost library with C++/CLI; can you give me an example of passing a lambda expression to an iterator/foldr function? What is the preferred way of exception handling? Can C++/CLI catch managed exceptions now? How well does dynamic IL generation work with C++/CLI? Does it run on Mono? Any other things I ought to know about?

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