title: Toolstripbutton not validating textbox
body: <p>I have a textbox, a standard button and a toolstrip containing a couple of buttons.
  In the validating event of the textbox I coded to check whether it is blank.
  If yes then it shows a message 'Enter Value'. When the standard button is clicked while
  the textbox is empty, it's validating properly and showing the message but when the
  toolstripbutton is clicked it's not validating the textbox and no message is shown. It seems that I've got to write the validation code explicitly in the
  <code>toolstripbutton_click</code> event which is too troublesome when there are multiple textboxes and toolstripbuttons on a single form.</p>
  
  <p>What I want to know is whether the <code>textbox_validating</code> can be fired when the toolstripbutton is clicked? Handling toolstrips is really a headache.</p>