title: WPF TextBox Overwrite
body: <p>In WPF, is there an easy to allow overwriting of text in an textbox?</p>
  
  <p>Thanks<br/>
  Tony</p>
  
  <p>EDIT: I guess i wasn't to clear. Sorry.</p>
  
  <p>I have a TextBox that the user is allowed to type 6 characters. If the user types 6 characters and then for whatever reason put the cursor at the start or somewhere in the middle of the 6 characters and starts to type, I want what they are typing to overwrite characters. Basically act like overwrite mode in Word. </p>
  
  <p>Thanks again.</p>