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c#.netwinformsdll-injectionspy++

Why Control.FromHandle(IntPtr) returns null in one hooked process and returns valid object of "Form"? in another hooked process?

I am facing a problem related to get out all the controls from some hooked process. My SpyDll launched into hooked process sucessfully, But when I check the statement

Control control = Control.FromHandle(MainWindowHandle), it returns null into control object where "MainWindowhandle"is just a native main window handle of that hooked process, which you always take from .NET "Process" class after launching that process.

But STRANGLY it happens that in some other hooked process which is the same C# .NET application, it returns valid object of Main "WinForm".

So why it will not work in above case? Are there any exceptions to use "MainWindowHandle" properly. In my case both are seperate .NET managed processes programmed in C#. Any process configuration needs to maintain specially while creating that process?

Regards Usman

Solution

  • 1.) Keep in mind, that there may be multiple appdomains and you can only get the control-objects of the current appdomain in the current process. Also you have to use the right ruuntime-version afaik, but I am not sure about that.

    2.) Why do you want the control handle anyways, it is much more convinient to work with native handles directly, you can even use the native functions from within another process, no dll injection. If you really need the managed control-objects, then check out the Application.OpenForms collection instead of that handle search!