Creates a hidden control in the selected form that is not visible on screen and is hidden from the user. A hidden control serves to include data that is transmitted together with the form.
在选定的表单中建立隐藏的控件。该控件不会显示在屏幕上，因此用户无法看到。隐藏的控件用于包含与表单一同传送的数据。