跨線程操作無效：從其創建線程以外的其他線程訪問

Question

我想在類文件方法中使用deletegate從異步調用的checklistbox（winform控件）中移除checked項。但它向我顯示了以下錯誤消息： -

跨線程操作無效：從其創建的線程以外的線程訪問控件'checkedListBox1'。

我已經嘗試過調用所需，但又得到了同樣的錯誤。示例代碼如下：

private void button1_Click(object sender, EventArgs e) 
{ 
    // Create an instance of the test class. 
    Class1 ad = new Class1(); 
    // Create the delegate. 
    AsyncMethodCaller1 caller = new AsyncMethodCaller1(ad.TestMethod1); 
    //callback delegate 
    IAsyncResult result = caller.BeginInvoke(checkedListBox1, 
          new AsyncCallback(CallbackMethod)," "); 
    } 

在類文件代碼TestMethod1是： -

private delegate void dlgInvoke(CheckedListBox c, Int32 str); 

private void Invoke(CheckedListBox c, Int32 str) 
{ 
    if (c.InvokeRequired) 
    { 
    c.Invoke(new dlgInvoke(Invoke), c, str); 
    c.Items.RemoveAt(str); 
    } 
    else 
    { 
    c.Text = ""; 
    } 

} 
// The method to be executed asynchronously. 

public string TestMethod1(CheckedListBox chklist) 
{ 
for (int i = 0; i < 10; i++) 
    { 
    string chkValue = chklist.CheckedItems[i].ToString(); 
    //do some other database operation based on checked items. 
    Int32 index = chklist.FindString(chkValue); 
    Invoke(chklist, index); 
    } 
return ""; 
} 

Answer 1

你確定你不是從該行代碼得到的錯誤？

string chkValue = chklist.CheckedItems[i].ToString();