全选

{

    for (var i=0;i<document.forms[0].elements.length;i++)

    {

        var e = document.forms[0].elements[i];

        if (e.type=='checkbox') 

        {

            var o=e.name.lastIndexOf('chbItem');

            if(o!=-1)

            {

                e.checked = box.checked;

             }

        }

    }

}