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  • WinForm中多线程操作控件

          在WinForm中的多线程中,操作控件时,会报无效操作异常,解决方法是调用System.Windows.Form.Control中BeginInvoke。
    代码如下:
    Code

    再看《CLR.via.C#.Second.Edition.Feb.2006》中是这么说,这下清楚了。
     
      
     In Windows, a window is always created by a thread, and this thread must be used to process
    all actions for the window. One reason for this is because  16-bit Windows versions were sin-
    gle-threaded operating systems, and in order to maintain backward compatibility, 32-bit and 64-
    bit versions of Windows kept the single-threaded architecture for handling window opera-
    tions such as WM_MOVE, WM_SIZE, WM_PAINT,  WM_CLOSE, etc. It's common for a Windows Forms
    application to use the asynchronous techniques explained in this chapter. However, since Win-
    dows Forms is built on top of Windows, a thread pool thread is not allowed to directly manipu-
    late a window; or more specifically, a class derived from System.Windows.Forms.Control.

        Fortunately, the System.Windows.Forms.Control class offers three methods—Invoke, Begin-
    Invoke
    , and EndInvoke-that you can call from any thread (including a thread pool thread) to
    marshal an operation from the calling thread to the thread that created the window. Inter-
    nally, Control's Invoke method calls the Win32 SendMessage method to have the window's
    thread execute a task synchronously. Control's BeginInvoke method internally calls the
    Win32 PostMessage method to have the window's thread execute a task asynchronously. If
    the calling thread wants to know when the window's thread has completed executing the
    task, it can call Control's EndInvoke method. If you don't care, this is one of the rare cases
    when you do not have to call an EndInvoke method.


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  • 原文地址:https://www.cnblogs.com/wintersun/p/1269255.html
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