function TrimString(strVal) 
{ 
	strTmp = strVal + ""; 
	if (strTmp.length == 0) 
		return (strTmp); 
	reVal = /^\s*/; 
	strTmp = strTmp.replace (reVal, ''); 
	reVal = /\s*$/; 
	return (strTmp.replace (reVal, '')); 
} 
function checkLogin()
{
	//alert(document.loginForm);
	if (TrimString(document.getElementById("Header1_Menu_login_txtUserID").value).length==0)
	{
		alert("用户名不能为空。");
		return false;
	} 
	if (TrimString(document.getElementById("Header1_Menu_login_txtPassWord").value).length==0)
	{
		alert("密码不能为空。");
		return false;
	} 
	return true;
}