function em(id){
	return document.getElementById(id);
}

function selectGroup(id,v){
	var el = document.getElementsByName("chkSelect");
	for (var i=0;i<el.length;i++){
		var e=el[i];
		if(e.getAttribute("groupId")==id)
			e.checked = v;
	}
}

function selectAll(v){
	var el = document.getElementsByName("chkSelect");
	for (var i=0;i<el.length;i++){
		el[i].checked = v;
	}
}

function doSelect(){
	var chks = document.getElementsByName("chkSelect");
	var selectedCount = 0;
	for(var i = 0; i < chks.length; i++){
		if(! chks[i].disabled && chks[i].checked){
			selectedCount++;
			break;
		}
	}
	if(selectedCount == 0){
		alert("请先选择");
		return false;
	}
	return true;
}

function setCookie(name,value){
    var Days = 30; //天
    var exp  = new Date();
    exp.setTime(exp.getTime() + Days*24*60*60*1000);
    document.cookie = name + "="+ escape (value) + ";expires=" + exp.toGMTString();
}
function getCookie(name){
    var arr = document.cookie.match(new RegExp("(^| )"+name+"=([^;]*)(;|$)"));
    if(arr != null) return unescape(arr[2]); return null;

}
function delCookie(name){
    var exp = new Date();
    exp.setTime(exp.getTime() - 1);
    var cval=getCookie(name);
    if(cval!=null) document.cookie= name + "="+cval+";expires="+exp.toGMTString();
}