javascript的一些小函数

function ShowHidden(objName)
{
var obj = document.getElementById(objName);
if (obj.style.display == "none")
{
obj.style.display = "block";
}
else
{
obj.style.display = "none";
}
}
function stringReplace(objString,oldString,newString)
{
var i;
var s2 = objString;
s2 = objString.split(oldString).join(newString);
return s2;
}
function CheckZip(str)
{
str = Trim(str);
var reg = /^\d+$/;
if(!reg.test(str))
return false;
return true;
}

function CheckTelphone(str)
{
str = Trim(str);
var reg = /^[\d|\-|\#|\(|\)]{0,20}$/;
if(!reg.test(str))
return false;
return true;
}
function havingSelected(drop)
{
if(drop.selectedIndex <=0)
{
return false;
}
return true;
}
function Trim(string) {
return string.replace(/(^\s*)|(\s*$)/g, "");
}

function IsEmpty(input) {
if (Trim(input.value) == '' || input.value == null) {
return true;
}
return false;
}

使用时：
var element = document.getElementById('TextBox_AssetNo');
if (element == null || Trim(element.value) == "") {
alert('请输入资产编号!!');
element.focus();
element.select();
return false;
}