title: How to have Checkbox as ColumnHeader of dataGridView
body: <p>I'm developing a window application in C# VS2005. I have a dataGridView in which the first column has Checkboxes. Now i want the Column header also to be a CheckBox which if i select all the Checkboxex in the column should get selected.
  How  can i do this.? 
  I referred the <a href="http://www.codeproject.com/KB/grid/DataGridView_winforms.aspx" rel="noreferrer">Code Project link</a></p>
  
  <p>But if i use that, if i click the <strong>FirstCell (not the Header)</strong> all the below cells are getting selected. But i want a CheckBox in the Column header. How can i do this.?</p>