title: Check all CheckBoxes in GridView
body: <p>I have a GridView in ASP.NET/C# with a CheckBoxField, a BoundField and 2 ButtonFields. All 4 of them has a header to make clear where the column stands for. At the Page_Load event I set the ВataЫource of the GridView to my filled DataTable.</p>
  
  <p>I want to make it easier to use for the user, and want to make a checkbox in the header. When that checkbox is checked by the user, all CheckBoxes should be checked in the GridView. I have set the HeaderText of the CheckBoxField to <code>&lt;input type='checkbox' /&gt;</code>, and it shows a checkbox in the header now.</p>
  
  <p>Now I want to add a function to that checkbox, that when it's checked, all CheckBoxes will be checked en vice versa. I tried to do it with jQuery, but it didn't work because I can't find a way to give all the CheckBoxes in the GridView the same ID or NAME.</p>
  
  <p>Is there a event that occurs when I check the HTML based checkbox within the header? If yes, which event?
  If no, how can i trigger a event when I check that checkbox, and change the GridView from my code-behind.</p>
  
  <p>And if none of that is possible, how can i do it on another way, with javascript, jQuery or maybe with a ASP.net control.</p>
  
  <p>I hope you can help me with this, but please don't expect i'm a code guru. I'm a intern at a company where the need a system, with this functionality.</p>
  
  <p><strong>Update:</strong></p>
  
  <p>Thank you everyone for helping me out. What is the easiest way to get the DataSource back into the DataTable, because i need to know which rows were selected and which were not?</p>