我遇到
Windows窗体应用程序的问题.
private delegate void DisplayDialogCallback();
public void DisplayDialog()
{
if (this.Invokerequired)
{
this.Invoke(new DisplayDialogCallback(DisplayDialog));
}
else
{
this.ShowDialog();
}
}
现在,每次运行它,都会抛出一个InvalidOperationException行this.ShowDialog();:
“跨线程操作无效：控制’SampleForm’从一个线程访问,除了它创建的线程.
这段代码怎么了？是不是有效的方式进行跨线程通话？ ShowDialog()有什么特别之处吗？
解决方法
尝试这个：
private delegate void DisplayDialogCallback();
public void DisplayDialog()
{
if (this.Invokerequired)
{
this.Invoke(new DisplayDialogCallback(DisplayDialog));
}
else
{
if (this.Handle != (IntPtr)0) // you can also use: this.IsHandleCreated
{
this.ShowDialog();
if (this.CanFocus)
{
this.Focus();
}
}
else
{
// Handle the error
}
}
}
请注意Invokerequired返回
true if the control’s Handle was
created on a different thread than the
calling thread (indicating that you
must make calls to the control through
an invoke method); otherwise,false.
因此,如果控件尚未创建,返回值将为false！
