if (txbValue.InvokeRequired)
txbValue.Invoke(new MethodInvoker(delegate() {
txbValue.Text = “test”;
}));
if (txbValue.InvokeRequired)
txbValue.Invoke(new MethodInvoker(delegate() {
txbValue.Text = “test”;
}));
原文：https://www.cnblogs.com/94cool/p/8523845.html