javascript to select all checkbox in gridview

i 开发者_开发问答am searching for the javascript that performs select all - deselect all feature in asp.net gridview.

So if a header checkbox is selected all the item templates checkbox should be selected. if any item template checbox is deselcted, the header checkbox should also be deselected.

Thanks

$('#GridView1 input[type=checkbox]').each(function(){
this.checked=!this.checked;});

Add this on 'select all' button click