title: closing a win form when datagridview has validation errors
body: <p>I'm using typed dataset in winforms app, .net 3.5 (VS 2010). A form has DataGridView. In FormClosing event I ask user to save changes. If user doesn't want to save I'd like to let the from close. However, when DataGridView has validation errors (I validate dataset in datatables's ColumnChanging event) the form won't close. Even if I do not catch FormCLosing event the form refuses to close. I guess I have to clear validation errors in datagridvIew somehow. Can someone suggest a solution?</p>
  
  <p>Edit: One more detail: the form is mdi child form. Needless to say, mdi parent won't close also.</p>