ColumnResizeDragging Property

// The client event ColumnResizeDragging takes two parameters sender and e
// sender  is the object which is raising the event
// e is the ColumnResizeDraggingEventArgs

       function WDG1_ColumnResizeDragging(sender, e) {

           //Returns which column is being used as the drag source for the resize action
           var column = e.get_column();

           //Gets the key of the column
           var key = column.get_key();

           //Gets the current width of the column
           var currentWidth = e.get_currentWidth();

           //Gets the starting width of the column before resizing
           var startingwidth = e.get_startingWidth();

           window.status = "The starting width of the column '" + key + "' is " + startingwidth + "and the current width is  " + currentWidth;
   }