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Hii
I want to make a text box which only accepts numbers. If any other key is pressed then it is discarded.
In VB6 it's done in somewhat like this .. on the KeyPress event we check if KeyAscii < '0' or KeyAscii >'9' then KeyAscii = 0
How can we implement this thing in C#
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You can use KeyPressed event handler:
<br />
void textbox_KeyPressed(Object o, KeyPressEventArgs e)<br />
{<br />
if(e.KeyChar < '0' || e.KeyChar > '9')<br />
e.Handled=true;<br />
}<br />
<br />
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There are several ways to do this. One way is to do an override of the Form's ProcessDialogKey method:
protected override bool ProcessDialogKey(Keys keyData)
{
if(this.textBox1.Focused)
{
char c = (char)keyData;
if(!char.IsNumber(c))
return true;
}
return base.ProcessDialogKey (keyData);
}
The graveyards are filled with indispensible men.
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I am interested in creating parsers, but I cannot find anywhere a decent site or book that explains this. I have found some info about top-down and bottom-up parsers, but I would like more details, differences and a good tutorial. Any help would be highly appreciated. Thanks a lot.
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You can find some info on antlr page which is a really good parser generator tool for C#:
http://www.antlr.org
I have few examples on my web page on using antrl: http://www.adersoftware.com/?page=compilers
I have also an example there that doesn't use parser generator, but uses hand coded top-down recursive descent parser.
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I have an ActiveX whiich I don't know it is written with wich language(I guess VB6). I also have .exp and .lib file for it. I want to use it in my .net application, when I add reference from COM tab, it say it can nor create wrapper class, maybe you have to register it. When I want to register it with regsvr32 I get this error:
D:\Documents and Settings\mazi\Desktop\Encrypt OCX\Project1.ocx was loaded, but the DllInstall entry point was not found.
This file can not be registered.
This means I can't import and use this file in .net? Any idea?
Mazy
"A bank is a place that will lend you money if you can prove that you don't need it." - Bob Hope
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It doesn't matter in which language a COM component was written, just like it doesn't matter in which language a .NET assembly was written (for different reasons, but similar in concept).
If you're adding an ActiveX control the correct way is through the toolbox. Customize your toolbox (for example, the Windows Forms or Components tab when a dialog or control is open in the designer) and find it in there. If it's not in there, then it does have to be registered. Adding a reference to your project is more for typelibs (similar to tlbimp.exe), where customizing your toolbox and dragging it on a design surface in your managed project will create an actual control wrapper (simimlar to aximp.exe), derived from AxHost. The latter still creates the typelib interop assembly as well.
Find the COM library and run the following:
regsvr32.exe Library.ext That will call the DllRegisterServer export. If you wedge a /u in between, it will call DllUnregisterServer and unregister your library.
Note also that the .lib (static library) and .exp (exports) files won't make a difference. These are really only useful in C/C++ applications (during the linking process).
Microsoft MVP, Visual C#
My Articles
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Ok Heath,it works now in awindows application nut I have to use it in a web service, when I initiate it there I got this error
Could not instantiate ActiveX control '0b6a9e9b-648e-11d8-9562-b4b5d2900919' because the current thread is not in a single-threaded apartment.
I know that there is property in ASP.NET exist name AspCompat which exactly solve this problem, but do you know about how to set it in web service?
Mazy
"A bank is a place that will lend you money if you can prove that you don't need it." - Bob Hope
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I take it you're trying to use this ActiveX control server-side, right? If not, you merely add the ActiveX control to the web page, which really has little to nothing to do with ASP.NET. Since you added it to a Windows Forms, I can only assume that it's a graphical ActiveX control which means that it most likely won't support the right threading models for multi-threaded use (which ASP.NET runs under), and won't have a Window container in which it's hosted.
Microsoft MVP, Visual C#
My Articles
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Heath Stewart wrote:
take it you're trying to use this ActiveX control server-side, right? If
Yes, it doesn't have any user interface.
So you mean I can't use it there? I don't know if that poor VB programmer can change his option for his ActiveX so it could run in MTA. But thats better for me , cause I can charge him and write that Activex myself 
Mazy
"A bank is a place that will lend you money if you can prove that you don't need it." - Bob Hope
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You might also try asking in the COM forum. Threading models is something I try not to mess with, and have hence avoided as much as possible. Someone there - like Mike Dunn if he visits - should be able to provide some suggestions (though a solution would require a little expertise in both COM threading models and ASP.NET).
Microsoft MVP, Visual C#
My Articles
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Thanks to Both of you, when I do it through Customize Toolbox I didn't got error,its strange, but I have to read Heath reply carefully first.
Mazy
"A bank is a place that will lend you money if you can prove that you don't need it." - Bob Hope
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Hi,
I would like to get a list of files and folders on a specific URL.
How can I do that?
I am searching for something like DirectoryInfo and FileInfo (thees two classes can onyl work with local files&folders aparently).
Q:What does the derived class in C# tell to it's parent?
A:All your base are belong to us!
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I tryed passing an URL to the constructor, but it says that URLs are not suported ...
I checked this article and I can't find anything about getting a list of files from a URL ...
Q:What does the derived class in C# tell to it's parent?
A:All your base are belong to us!
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CWIZO wrote:
I checked this article and I can't find anything about getting a list of files from a URL ...
Look at the picture of article, it gets IP address with username and password. And in the tab of sample application ,you will see MY EXPLORER . So isn't it what you want?
Mazy
You're face to face,
With the man who sold the world - David Bowie
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By the way, if it doesn't help,you can use remotng to run a application on server to respond to your application and send information you need.
Mazy
You're face to face,
With the man who sold the world - David Bowie
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The problem is that the server is "random". It can be any server.
So I can't have autherication or something.
Im building something like a spider, that would grab images from a server for instance (no I am not making a pr0n downloader  ).
Q:What does the derived class in C# tell to it's parent?
A:All your base are belong to us!
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CWIZO wrote:
So I can't have autherication or something.
You missed some point , there is something called security,unless you wanna do hacking.
Mazy
"A bank is a place that will lend you money if you can prove that you don't need it." - Bob Hope
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To demonstrate what I'm trying to achive please download&install this programm:
http://sbl.net/Downloads/BlackWidow%20Setup.exe
it is called Black Widow, you just type in a URL, and the program generates a structure of files and folders. And if files are accessible (like images, or html files) you can download them.
Q:What does the derived class in C# tell to it's parent?
A:All your base are belong to us!
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I would like to get rid of (actually move) the arrow in the menu item which is used to show the existence of menu items to the right of the menu item. The reason for this is that I need to show the menu on the right hand side of the form and when I change the RightToLeft property, the arrow appears in the center of the menu item. I've made several different attempts but to no avail. It doesn't seem to matter whether I use owner draw or not. Can somebody help?
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There's plenty of articles here on CodeProject about owner drawing menus. Just try a search[^].
There's also a pretty basic - but complete - example on Dr. GUI .NET some time back, Controls and Icons a la .NET[^]. The example is in VB.NET, but if you truly understand the .NET Framework, you'll have no problems translating it to C# if you need that. There's also a pretty good "Cutting Edge" article in MSDN Magazine, Owner-drawing in .NET[^], which deals completely with menus.
Microsoft MVP, Visual C#
My Articles
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Thanks but I still don't see from these articles what to do in order to get rid of the arrows. They are always drawn when one or more submenus are added to a menu item (to its right). These arrows appear in black while viewing the menu item and in white when selecting (hovering over) it. This occurs regardless of which colors are set in the DrawString or FillRectangle methods (in the owner draw procedure).
I put some debugging print statements into an overridden WndProc method, but I fail to see which event (in Message) would do this drawing.
I also attempted to create a graphics object in the MenuItemPopUp method but when I attempted to create such an object from the handle I received from the sender (MenuItem) the program just crashed giving me an out of memory error msg. Seems like creating a graphics object from the window handle of the form object is allowed but doing the same from the window handle of the menu is not. (Although, even if this had succeeded I have my doubts as to whether this would solve my problem).
So, if anybody out there has succeeded in getting rid of (or moving) these arrows, I would appreciate it if you could tell me.
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The MenuItem.DrawItem event gives you the the Graphics object you should be using. It's possible the out-of-memory exception is because a Graphics object has already been created from the window handle, which obtained the HDC internally. There can only exist one HDC for the drawing operation, IIRC.
I threw together a quick test and see what you mean. Unfortunately, .NET probably has nothing to do with this since it merely encapsulates the Windows APIs. You could always try adjusting the SizeF in which the text is drawn so that the menu item is long enough to display some space between the arrow and the text. I have heard that there are some quirks in right-to-left reading orders, and this appears to be one. Googling for this subject pretty much comes up with that idea - offsetting your text appropriately.
Microsoft MVP, Visual C#
My Articles
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Thank you for your response and for trying this out with a test program. I increased the width of the menu item window in MeasureItem and it does look better. Unfortunately, the arrows are on the wrong side of the text and are pointing in the wrong direction. What really baffles me is that I can't find the Windows API message which probably repaints the Menu item after I paint it in DrawItem. This message ought to be one of the messages coming through the WndProc method.
By the way the out-of-memory exception I get is not in MenuItem.DrawItem but in the PopUp event method. It happens when I attempt to create a Graphics object from the window handle of the MenuItem. I wonder whether this is a bug in .NET (with C#).
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