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Re: C# communication with events MusicAlly10-Feb-04 16:54 MusicAlly 10-Feb-04 16:54  Hi David, Thanks for your feedback. I'll try to give a concise and accurate explanation of what I'm trying to do. When I referred to events in my original post I did mean delegates. In MFC I wrote a generic subsystem in which there existed the notions of Senders, Receivers, Messages, and the global messaging system (a singleton) which took care of passing on events of interest to appropriate parties (Receivers). Forget about Senders, that was a construct just to facilitate some nuance. So the important things are Receivers and Messages. Receivers are full blown classes which are doing some work within the system. Messages are also classes in their own right, and the nub of the system was that any receiver could register interest in any message, in particular specifying a function on the receiver class itself which would be invoked when that particular message was broadcast by some other object in the system. The whole thing hung together with a load of templated classes, functions etc. This system is a variant of Subject-Observer/Multicast. Of course in C# we have beautiful constructs (like Java) such as retrieving all the methods for a given type, which makes life much easier because you can invoke a method against a particular object which was much more difficult in C++ for reasons I won't go into here. Anyway, in C++ the global messaging system singleton executed in its own thread, and when some object wanted to broadcast a message they would obtain a lock on the singleton, call a method to broadcast said message and the singleton would then propagate this message to all interested objects by queueing the message for each thread, the singleton would then use the PostThreadMessage to indicate to the thread that messages were waiting for it, and when the thread received the context and the method referred to through the message map by the parameter to PostThreadMessage was executed, all messages queued up for that thread would then be propagated to the appropriate objects. So what I was hoping to gain from the delegates/events was that I would be able to fire an event from the singleton to all threads and that an object within each thread would respond to said event and then retrieve all messages queued for objects instantiated within the context of their thread. Am I going in the right direction do you think? I can supply a code example of what I'm trying if it would make things clearer. Thanks, Alastair. Re: C# communication with events Heath Stewart11-Feb-04 3:52 Heath Stewart 11-Feb-04 3:52  A similar way is possible using an object-oriented framework like .NET. Instead of thinking procedurally, though, thing about how these objects react with each other, or with other objects. For instance, you could code an event on the object that starts all the threads, for which they would handle. You should invoke these delegates attached to the event in an asynchronous manner, most likely. You could also add events to the threaded object but then the invoking class has to keep track of them and add and remove delegates. The first way makes more sense. One thing that may help is that the C# compiler (I believe the VB.NET compilers does as well) generates synchronous (Invoke) and asynchronous invocation methods (BeginInvoke, EndInvoke). that are visible in the code editor when the delegates are declared in the current project. For more on asynchronous calls in .NET, see Including Asynchronous Calls[^] in the .NET Framework SDK. It seem, though, like you are headed in the right direction. The only thing you have to watch out for is that you invoke the methods from the calling thread in the thread that contains the object.   Microsoft MVP, Visual C# My Articles Compiler Optimizations Andrew Shapira10-Feb-04 13:44 Andrew Shapira 10-Feb-04 13:44  Where is a discussion of the current and future optimizations that the C# compilers do? When I see things like the following I start to question my faith in csc being good at optimizing. (The same kind of thing shows up in cordbg when looking at the JIT code for a similar example.) % cat y.cs using System; class A { bool On { get { return true; } } public void Print() { if (On) { Console.WriteLine("On"); } } } class ConditionalTest { static void Main() { A a = new A(); a.Print(); } } % csc /optimize+ y.cs Microsoft (R) Visual C# .NET Compiler version 7.10.3052.4 for Microsoft (R) .NET Framework version 1.1.4322 Copyright (C) Microsoft Corporation 2001-2002. All rights reserved. % ildasm y.exe .method public hidebysig instance void Print() cil managed { // Code size 19 (0x13) .maxstack 2 IL_0000: ldarg.0 IL_0001: call instance bool A::get_On() IL_0006: brfalse.s IL_0012 IL_0008: ldstr "On" IL_000d: call void [mscorlib]System.Console::WriteLine(string) IL_0012: ret } // end of method A::Print % At least the compiler eliminates the "if" test when "On" is replaced with "true" in the test. VS-style colors Judah Gabriel Himango10-Feb-04 10:30 Judah Gabriel Himango 10-Feb-04 10:30  Visual Studio has the nifty-looking selection colors when you hover over the main menu. I am in the process of writing a custom control, and I would like to use those colors (Windows Theme-depended obviously) for the selection mechanism in my custom control. It seems System.Drawing.SystemColors isn't the proper way to get them; I can't find a SystemColor that is the correct color across all Windows Theme skins; for example, using the standard Blue Luna theme, SystemColors.InactiveCaptionText is the correct color for the internal region of the selection. However, using the Olive theme, that is not the correct color. How can I get the correct colors needed to draw a VS-style selection? Thanks ahead of time. The graveyards are filled with indispensible men. Re: VS-style colors Heath Stewart10-Feb-04 11:33 Heath Stewart 10-Feb-04 11:33  Sometimes Microsoft changes the normal colors of a control by changing the RGB components, like adding the difference between the current color and FF (for each component). This will lighten the color. There are also SystemColors that should already have such values, too, like ControlLight and ControlLightLight. You could try these as well.   Microsoft MVP, Visual C# My Articles Re: VS-style colors Uwe Keim11-Feb-04 1:47 Uwe Keim 11-Feb-04 1:47  One thing I dislike about several (pseudo-)commerical GUI libs is their lack of being nicely when used in RemoteDesktop sessions (or Citrix) with only 256 (or fewer) colors: Usually they are just horrible dithered. Only some libraries I examined behave good in this area. -- - Free Windows-based CMS: www.zeta-software.de/enu/producer/freeware/download.html - See me: www.magerquark.de - MSN Messenger: uwe_keim@hotmail.com Re: VS-style colors Judah Gabriel Himango11-Feb-04 4:48 Judah Gabriel Himango 11-Feb-04 4:48  I wrote a program to go through all the SystemColors and compare them with what Visual Studio uses. The result was that there were some colors that Visual Studio uses (for instace, to draw a Visual Studio menu using the Luna Blue theme, SystemColors.Highlight can be used for the outer border, and SystemColors.InactiveCaptionText can be used for the inner region). However, if I switch themes, say to the Olive theme, SystemColors.Highlight and SystemColors.InactiveCaptionText no longer are the correct colors. In addition to checking all the SystemColors, I've also check through all system colors put through ControlPaint.Dark, .DarkDark, .Light, and .LightLight and still haven't found the correct colors! Ack. The graveyards are filled with indispensible men. Re: VS-style colors Heath Stewart11-Feb-04 5:12 Heath Stewart 11-Feb-04 5:12  As I mentioned before, another thing they sometimes do is modify the RGB components of the color to get such an effect (adding to lighten, subtracting to darken). You could do the same thing if the SystemColors don't work for you.   Microsoft MVP, Visual C# My Articles Programmatic mouse movement Darryl Borden10-Feb-04 10:29 Darryl Borden 10-Feb-04 10:29  Does anyone know how to programmatically position the mouse on a control in c#? Darryl Borden Principal IT Analyst darryl.borden@elpaso.com Re: Programmatic mouse movement Judah Gabriel Himango10-Feb-04 10:33 Judah Gabriel Himango 10-Feb-04 10:33  Cursor.Position = somePoint; If you want to limit that point to be on the control, use the control's .PointToClient method. For example, Point somePoint = new Point(0,0); Cursor.Position = myControl.PointToClient(somePoint); The graveyards are filled with indispensible men. Debugging into a reference gordingin10-Feb-04 10:23 gordingin 10-Feb-04 10:23  I am new to .NET. I have 1 solution with 2 projects. Project 2 compiles into a class library which is reference from Project 1. I wish to walk into the source of my reference during debug. Can I do this? BTW, both projects are set to debug... Thanks Ralph Re: Debugging into a reference Bill Dean10-Feb-04 10:29 Bill Dean 10-Feb-04 10:29  Should work just fine...just set your break points and launch it. Re: Debugging into a reference gordingin10-Feb-04 10:34 gordingin 10-Feb-04 10:34  Thanks but it doesn't. So here is a bit more info. Project 1 is a ASP.NET application, so I lauch a web page. I wish to trace into the method that is in the reference. So if I CAN'T trace into the method, what should I check... Thanks Ralph Re: Debugging into a reference Heath Stewart10-Feb-04 11:35 Heath Stewart 10-Feb-04 11:35  Debugging has to be enabled on the server. In IIS, you can configure this in the Application Configuration. The .NET Framework debugging tools (from the SDK) also have to be installed (from what I've read), so install the SDK on the server (not just the runtime). There is a lot of documentation on this in the KB at http://support.microsoft.com[^].   Microsoft MVP, Visual C# My Articles Re: Debugging into a reference gordingin11-Feb-04 3:57 gordingin 11-Feb-04 3:57  Thanks for all the help. I realized (later) that these were stubs, RPC calls to the server... parallel port Member 87345210-Feb-04 7:51 Member 873452 10-Feb-04 7:51  hi all I want to trace the parallel port & serial port thanks;) Re: parallel port Marc Clifton10-Feb-04 8:39 Marc Clifton 10-Feb-04 8:39  waleedkadry wrote: I want to trace the parallel port & serial port What do you mean by trace? Marc Latest AAL Article My blog Join my forum! Re: parallel port Marc Clifton10-Feb-04 9:41 Marc Clifton 10-Feb-04 9:41  Use the driver found here: http://driverlinx.com/DownLoad/dnload.htm#Windows%2095/NT%20Port%20I/O%20Driver[^] and write a small unmanaged DLL to get the data into C#. Marc Latest AAL Article My blog Join my forum! Better yet... Marc Clifton10-Feb-04 9:42 Marc Clifton 10-Feb-04 9:42  Just do what this article says to do for reading the port: http://www.codeproject.com/csharp/csppleds.asp[^] Marc Latest AAL Article My blog Join my forum! Re: parallel port mohdshiraz10-Feb-04 18:27 mohdshiraz 10-Feb-04 18:27  if u mean to read and send data to ports there are numbers of ways. for parallel port u can use outport and inport commands. for serial port it is little more difficult. there are number of article in codeproject itself build order of projects godzooky10-Feb-04 7:45 godzooky 10-Feb-04 7:45  how do i specify the build order of the projects in a solution? for example, if i have a deployment project in a solution, how do i make that build last, so the deployment project will include the latest versions of the assemblies? Re: build order of projects Marc Clifton10-Feb-04 8:41 Marc Clifton 10-Feb-04 8:41  godzooky wrote: for example, if i have a deployment project in a solution, how do i make that build last, so the deployment project will include the latest versions of the assemblies? The projects are built based on reference dependency. This is why you can't have circular references in your projects. You're deployment project should reference the projects on which it depends, and therefore will be built last. Marc Latest AAL Article My blog Join my forum! Updating a windows datagrid? Anonymous10-Feb-04 7:27 Anonymous 10-Feb-04 7:27  Hi, I'm new to the windows datagrid control. I'm trying to create an application that displays the contents on an access database. I've got that part working so far; my question is how can I have the datagrid & access database accept any changes that the user enters into the datagrid. Is their a way for the datagrid's contents to be dumped into the access database after a change is made? I don't want to do it manually, it could get messy. Thanks Re: Updating a windows datagrid? Mazdak10-Feb-04 9:37 Mazdak 10-Feb-04 9:37  You have to take look at htese class: Use a OleDbDataADapter to fill a DataSet and bind it to DataGrid, then each change reflected to datagrid, you can update access database with OleDBdDataAdapter.Update() method. If you search for these classes you can find samples in this site and MSDN. Mazy "Improvisation is the touchstone of wit." - Molière Re: Updating a windows datagrid? MrJJKoolJ10-Feb-04 13:13 MrJJKoolJ 10-Feb-04 13:13  Hi Mazy, I have a datagrid in win form that when a change to a record on that same form occurs how can I get the datagrid to refresh with new updates? I have the datagrid bound to a dataview. So some how need way to update the dataview I'm guessing. Thanks, JJ

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