Check uncheck all checkboxes in a gridview using javascript

Step 1:



Put this script below head tag

<script type="text/javascript" language="javascript">

function changeCheckState(chk)

{

var frm = document.forms[0];

for (i=0; i<frm.length; i++)

{

if (frm.elements[i].id.indexOf('checkBox') != -1)

{

frm.elements[i].checked = chk;

}

}

}



</script>

Step :2



Put this checkbox in header template

<asp:CheckBox ID="checkBox" runat="server" />

Step 3:



Put this checkbox in Itemtemplate

<input id="changeCheckStateId" onclick="changeCheckState(this.checked);" runat="server"

type="checkbox" />