function checkAll(e, itemName)
    {    
        var aa = document.getElementsByName(itemName);    //获取全选复选框
        for (var i=0; i<aa.length; i++){
         aa[i].checked = e.checked;    //改变所有复选框的状态为全选复选框的状态
        }
    }

    function checkItem(e, allName)
    {
        var all = document.getElementsByName(allName)[0];    //获取全选复选框
        if(!e.checked){
            //没被选中全选复选框置为false;
            all.checked = false;
        } else{
            //选中，遍历数组
            var aa = document.getElementsByName(e.name);
            for (var i=0; i<aa.length; i++)
                //只要数组中有一个没有选中返回。假如所有的都是选中状态就将全选复选框选中;
             if(!aa[i].checked) return;    
            all.checked = true;
        }
    }

	
//反选
function ReSel(e, itemName){
    var aa = document.getElementsByName(itemName);
    for(var i=0; i<aa.length; i++){
        if(aa[i].checked) aa[i].checked = false;
        else aa[i].checked = true;
    }
}
//全选
function SelAll(e, itemName){
  var aa = document.getElementsByName(itemName);    //获取全选复选框
        for (var i=0; i<aa.length; i++){
         aa[i].checked = true;    //改变所有复选框的状态为全选复选框的状态
        }
}

//取消
function NoneSel(e, itemName){
   var aa = document.getElementsByName(itemName);    //获取全选复选框
        for (var i=0; i<aa.length; i++){
         aa[i].checked = false;    //改变所有复选框的状态为全选复选框的状态
        }
}