Check and Uncheck All Checkboxes in a DataList using ASP.NET and C#

Here's the client-side javascript function in the aspx page


function CheckAll(checkAllBox, fieldName)
{
var frm = document.Form1;
var actVar = checkAllBox.checked;
for(i = 0; i < frm.length; i++)
{
e = frm.elements[i];
if (e.type == 'checkbox' && e.name.indexOf(fieldName) != -1)
e.checked = actVar ;
}
}


function UnCheckAll(fieldName)
{
var frm = document.frmAdsKeyword;
for(i = 0; i < frm.length; i++)
{
e = frm.elements[i];
if (e.type == 'checkbox' && e.id.indexOf(fieldName) != -1)
e.checked = false ;
}
return false;
}