C # Windows Forms MessageBox the top display --xdd

method 1.

MessageBox.Show("Text", "Caption", MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1, MessageBoxOptions.ServiceNotification);

Method 2.

MessageBox.Show("Text", "Caption", MessageBoxButtons.OK, MessageBoxIcon.Information, MessageBoxDefaultButton.Button1, MessageBoxOptions.DefaultDesktopOnly);

More information for the MessageBox: https://blog.csdn.net/C_gyl/article/details/85336605