checkbox全选和全反选

<script language="javascript">
        ///设置全选
        function SelectAllCheckboxes(spanChk,chkboxname){
　var oItem = spanChk.children;
　var theBox=(spanChk.type=="checkbox")?spanChk:spanChk.children.item[0];
　xState=theBox.checked;
　elm=theBox.form.elements;
　for(i=0;i<elm.length;i++)
　if(elm[i].type=="checkbox" && elm[i].id!=theBox.id)
　{
　　if(elm[i].checked!=xState && elm[i].id.indexOf(chkboxname) != -1)
　　elm[i].click();
　}
　
　document.getElementById("chkAllreverse").checked=false;
}

///设置反选
function SelectReverseChekboxes(spanChk,chkboxname){

　var oItem = spanChk.children;
　var theBox=(spanChk.type=="checkbox")?spanChk:spanChk.children.item[0];
　xState=theBox.checked;
　elm=theBox.form.elements;
　for(i=0;i<elm.length;i++)
　if(elm[i].type=="checkbox" && elm[i].id!=theBox.id)
　{
　　if( elm[i].id.indexOf(chkboxname) != -1)
　　    elm[i].click();
　}
　
　　document.getElementById("chkAll").checked=false
}

  </script>

 

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<input id="chkAll" runat="server" onclick="javascript:SelectAllCheckboxes(this,'sel');" type="checkbox" />全选
                                                               
<input id="chkAllreverse" runat="server" onclick="javascript:SelectReverseChekboxes(this,'sel');" type="checkbox">反选

 

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注:
sel 是 gridlist 中的 checkbox名
chkAll 是全选checkbox
chkAllreverse 是全反选checkbox