function check() {
	var oo = document.getElementsByName( "UserName" )[0];
	if ( oo.value == "" ) {
	alert( "用户名不得为空！" );
	oo.select();
	return false;
	}
	oo = document.getElementsByName( "Password" )[0];
	if ( oo.value == "" ) {
	alert( "密码不得为空！" );
	oo.select();
	return false;
	}
	return true;
}


	function checkDemo() {
		var oo = document.getElementsByName( "UserName" )[1];
		if ( oo.value == "" ) {
		alert( "用户名不得为空！" );
		oo.select();
		return false;
		}
		oo = document.getElementsByName( "Password" )[1];
		if ( oo.value == "" ) {
		alert( "密码不得为空！" );
		oo.select();
		return false;
		}
		return true;
	}