JS全选代码,兼容IE，FF，Chrome

//全选代码。兼容IE，FF，Chrome
function checkAll(chk)
{
var ck = document.getElementsByTagName("input"); //找到页面上所有input节点
for (var i = 0; i < ck.length; i++)
{
if (ck[i].type == "checkbox" && ck[i].disabled != true)           {ck[i].checked = chk;}
}
}