Javascript to select all check box from datagrid

Write Following function in

tag.

function CheckAll(dgView)
{
var datagrid = document.getElementById(dgView);
for (var i=0;i < datagrid.rows.length;i++)
{
var e = datagrid.rows[i].cells[0];
for (k=0; k < e.childNodes.length; k++)
{
if ((e.childNodes[k].type=='checkbox'))
{
e.childNodes[k].checked=true;
}
}
}
}

Call above function on button click event by passing datagrid object as a parameter.