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();
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);
}
}
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());