js获取GridView中CheckBox的选中状态

<script language="javascript">
function show()
{
var ele = event.srcElement;
if(ele.tagName == "INPUT" && ele.type == "checkbox")
{
var text = ele.parentElement.title;
if(ele.checked == true)
{
alert(text + "已被勾选");
}
else
{
alert(text + "已取消勾选");
}
}

}
</script>

/*============================GriView列表项绑定事件==========================*/

 protected void gvListInfo_RowDataBound(object sender, GridViewRowEventArgs e)    {           CheckBox chk = (CheckBox)e.Row.FindControl("x_chkID");           chk.Attributes["OnClick"] = "javascript:show();";    }