请编程遍历页面上所有TextBox控件并给它赋值为string.Empty？

foreach (System.Windows.Forms.Control control in this.Controls)
{
   if (control is System.Windows.Forms.TextBox)
   {
    System.Windows.Forms.TextBox tb = (System.Windows.Forms.TextBox)control ; 
    tb.Text = String.Empty ;
   }
}