【转发】Cross-thread operation not valid: Control 'progressBar1' accessed from a thread other than the thread it was created on

当您试图从单独的线程更新一个win form时，您将得到如下错误信息： 

"Cross-thread operation not valid: Control 'progressBar1' accessed from a thread other than the thread it was created on." 

 

本文将介绍如何处理此错误：

问题：

 

重现该错误, 添加一个 progress bar 控件 (progressbar1) 以及一个  button(btnStart)到您的窗体上：.

private void btnStart_Click(object sender, EventArgs e)
{
progressBar1.Minimum = 0;
progressBar1.Maximum = 100;

System.Threading.Thread t1 = new System.Threading.Thread(startProgress);
t1.Start();
}
void startProgress()
{
for (int i = 0; i {
progressBar1.Value = i; //You will get error at this line
System.Threading.Thread.Sleep(100);
}
}

window.google_render_ad();

解决方案：

private void btnStart_Click(object sender, EventArgs e)
{
progressBar1.Minimum = 0;
progressBar1.Maximum = 100;

System.Threading.Thread t1 = new System.Threading.Thread(startProgress);
t1.Start();
}
void startProgress()
{
for (int i = 0; i {
SetControlPropertyValue(progressBar1, "value", i); //This is a thread safe method
System.Threading.Thread.Sleep(100);
}
}

delegate void SetControlValueCallback(Control oControl, string propName, object propValue);
private void SetControlPropertyValue(Control oControl, string propName, object propValue)
{
if (oControl.InvokeRequired)
{
SetControlValueCallback d = new SetControlValueCallback(SetControlPropertyValue);
oControl.Invoke(d, new object[] { oControl, propName, propValue });
}
else
{
Type t = oControl.GetType();
PropertyInfo[] props = t.GetProperties();
foreach (PropertyInfo p in props)
{
if (p.Name.ToUpper() == propName.ToUpper())
{
p.SetValue(oControl, propValue, null);
}
}
}
}

您可以通过该解决方案来处理所有的WIndows 控件. 您所要做的是, 从上方的代码中copy SetControlValueCallback delegate 以及SetControlPropertyValue 函数 function.

例如您想设置一个 label的内容, 使用SetControlPropertyValueSetControlPropertyValue(Label1, "Text", i.ToString());

 

请确认您所应用的属性的值类型.在上面的Demo中 Text 是一个 string 属性. 这就是我为什么将其转换为String。