跨线程操作无效：控制“从创建它的线程以外的线程访问 [英] cross-thread operation not valid: Control " accessed from a thread other than the thread it was created

问题描述

每一个，



i有一种方法，我想在面板控件中显示图像。

我先放这个图片在图片框中，然后我将它添加到面板控件。



i我使用两个线程，但它给我错误，因为我在这个问题的提交中提到。



错误我上线

this.agentbox.left = px;



请有人给我建议。

  private  委托  void  DrawOnPanelCircleDelegate（Point pp，Bitmap r）; 
  public   void  DrawOnPanelCircle（Point p，Bitmap ratImage）
 {
 
  if （InvokeRequired）
 {
 DrawOnPanelCircleDelegate drwOnPanelCircle =  new  DrawOnPanelCircleDelegate（（pp，r）= >  DrawOnPanelCircle（p，ratImage））; 
  this  .BeginInvoke（drwOnPanelCircle， new   object  [] {p，ratImage}）; 
} 
 
 
  lock （_locker）
 {
  this  .agentBox .Image = ratImage; 
  this  .agentBox.SizeMode = PictureBoxSizeMode.StretchImage; 
 
  //   this.Invoke（（MethodInvoker）委托 
  //   { 
 此 .agentBox.Left = pX; 
  this  .agentBox.Top = pY; 
  //  }）;  
 
 
  //   Application.DoEvents（）;  
 
 
} 

解决方案

我不知道你发布了一个单独的问题（这是正确的事情，并刚刚回答：如何在图像上绘制多个图像并通过图片框显示 [ ^ ]。

-SA

尝试

调用事件而不用担心跨线程异常 [ ^ ]

http://msdn.microsoft.com/en-us/library/ms171728%28v=vs.85% 29.aspx [ ^ ]

hi every one,

i have a method in which i want to display an image in the panel control.
first i put this picture in the picturebox then i add it to the panel control.

i am using two threads but it give me the error as i have mentioned in the subjection of this question.

error i am getting at line
this.agentbox.left = p.x;

anybody could give me suggestion please.

private delegate void DrawOnPanelCircleDelegate(Point pp, Bitmap r );
       public void DrawOnPanelCircle(Point p, Bitmap ratImage)
       {

           if (InvokeRequired)
           {
               DrawOnPanelCircleDelegate drwOnPanelCircle = new DrawOnPanelCircleDelegate((pp, r) => DrawOnPanelCircle(p, ratImage));
               this.BeginInvoke(drwOnPanelCircle, new object[] { p, ratImage });
           }


           lock (_locker)
           {
               this.agentBox .Image = ratImage;
               this.agentBox.SizeMode = PictureBoxSizeMode.StretchImage;

               //this.Invoke((MethodInvoker)delegate
               //{
                   this.agentBox.Left = p.X;
                   this.agentBox.Top = p.Y;
               //});  
               
              
              // Application.DoEvents();


           }

解决方案

I did not know that you posted a separate question (which was right thing to do) and just answered: how to draw more than one images on an image and to display through picturebox[^].

—SA

Try
Invoking events without worrying about cross-thread exceptions[^]
http://msdn.microsoft.com/en-us/library/ms171728%28v=vs.85%29.aspx[^]

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