title: Excel & EPPlus .NET library: Advanced DropDown list validation
body: <p>In Epplus, when we create a DropDown list for some cells in excel file, then user put a value which is not part of the list, the cell show a message says: value must match one of the listed items.</p>
  
  <p>Instead of this message, Is it possible to prevent the user to put a value which is not part of the drop down list?</p>
  
  <p>Thanks in advance,</p>