function trim(s){
 	return rtrim(ltrim(s)); 
}
function ltrim(s){
 	return s.replace( /^\s*/, ""); 
} 
function rtrim(s){ 
 	return s.replace( /\s*$/, ""); 
}
function isEmpty(s){
	s = trim(s); 
	return s.length == 0; 
}
function isEmail(s){
	s = trim(s); 
 	var p = /^[_\.0-9a-z-]+@([0-9a-z][0-9a-z-]+\.){1,4}[a-z]{2,3}$/i; 
 	return p.test(s);
}
function isNumber(s){
	return !isNaN(s); 
}
function $() {
  var elements = new Array();

  for (var i = 0; i < arguments.length; i++) {
    var element = arguments[i];
    if (typeof element == 'string')
      element = document.getElementById(element);

    if (arguments.length == 1)
      return element;

    elements.push(element);
  }

  return elements;
}
function isColor(s){ 
	s = trim(s); 
	if (s.length !=7) return false; 
	return s.search(/\#[a-fA-F0-9]{6}/) != -1; 
}
function isMobile(s){ 
	s = trim(s); 
	var p = /13\d{9}/; 
	return p.test(s);
}
function isCard(s){ 
	s = trim(s); 
	var p = /^\d{15}(\d{2}[xX0-9])?$/; 
	return p.test(s);
}
//URL;
function isURL(s){
	s = trim(s).toLowerCase();
	var p = /^http:\/\/[A-Za-z0-9]+\.[A-Za-z0-9]+[\/=\?%\-&_~`@[\]\':+!]*([^<>\"\"])*$/;
	return p.test(s);
}
//Phone;
function isPhone(s){
	s = trim(s);
	var p = /^((\(\d{3}\))|(\d{3}\-))?(\(0\d{2,3}\)|0\d{2,3}-)?[1-9]\d{6,7}$/;
	return p.test(s);
}
//Zip;
function isZip(s){
	s = trim(s);
	var p = /^[1-9]\d{5}$/;
	return p.test(s);
}
//Double;
function isDouble(s){
	s = trim(s);
	var p = /^[-\+]?\d+(\.\d+)?$/;
	return p.test(s);
}
//Integer;
function isInteger(s){
	s = trim(s);
	var p = /^[-\+]?\d+$/;
	return p.test(s);
}

//English;
function isEnglish(s){
	s = trim(s);
	var p = /^[A-Za-z]+$/;
	return p.test(s);
}
function isChinese(s){
	s = trim(s);
	var p = /^[\u0391-\uFFE5]+$/;
	return p.test(s);
}
function isDoubleChar(s){
	var p = /^[^\x00-\xff]+$/;
	return p.test(s);
}
function hasChineseChar(s){
	var p = /[^\x00-\xff]/;
	return p.test(s);
}
function hasAccountChar(s){
	var p = /^[a-zA-Z0-9][a-zA-Z0-9_-]{0,15}$/;
	return p.test(s);
}
function limitLen(s,Min,Max){
	s=trim(s);
	if(s=="") return false;
	if((s.length<Min)||(s.length>Max))
		return false;
	else
		return true;
}
function showtips(obj,msg)
{
	try{
		$(obj).innerHTML = "<font color='red'>" + msg + "</font>";
	}catch(e){}	
}
function isnull(objname,tips){
	var obj = $(objname);
	if (trim(obj.value) == ""){
		if(arguments.length>2)
			showtips(arguments[2],tips);
		else
			alert(tips);
		try{obj.focus();obj.select();}catch(e){}
		return true;
	}
	return false;
}
function notnumber(objname,tips){
	var obj = $(objname);
	if (isNaN(trim(obj.value))){
		alert(tips);
		try{obj.focus();obj.select();}catch(e){}
		return true;
	}
	return false;
}

//discount;
function isDiscount(objname,tips){
	var obj = $(objname);
	if (obj.value < 0 || obj.value > 100)
	{
		alert(tips);
		try{obj.focus();obj.select();}catch(e){}
		return true;
	}
}