js根据中英验证用户名提示

function chkUserEmail( str,language )
{
 var language = (arguments[1]!='')?arguments[1]:'CN';
 if( str.Trim() == '' ){
  if(language == 'EN')
  {
   window.alert( "Please enter your email address!" );
  }
  else
  {
   window.alert( "请输入您的E-mail地址 ！" );
  }
  return false;
 }
 return chkUserEmailFormat( str,language );
}

function chkUserEmailFormat( str,language )
{
 var language = (arguments[1]!='')?arguments[1]:'CN';
 
 if( str.Trim().length > 100 ){
  if(language == 'EN')
  {
   window.alert( "Your email address should not have more than 100 characters!" );
  }
  else
  {
   window.alert( "email地址长度不能超过100位!" );
  }
  return false;
 }
 str = str.toLowerCase().Trim()
 if( isEmail(str) ){
  return true;
 }else{
  if(language == 'EN')
  {
   window.alert( "Please use correct email address!" );
  }
  else
  {
   window.alert ( "Email书写不正确！" );
  }
  return false;
 }
}

function chkUserName( str,language )
{
 var language = (arguments[1]!='')?arguments[1]:'CN';
 
 if( str.Trim() == '' ){
  if(language == 'EN')
  {
   window.alert( "Please enter your member ID!" );
  }
  else
  {
   window.alert( "请输入用户名！" );
  }
  return false;
 }
 if( str.Trim().length < 4 ){
  if(language == 'EN')
  {
   window.alert( "Your member ID should have more than 3 characters!" );
  }
  else
  {
   window.alert( "您的用户名需大于3位 ！" );
  }
  return false;
 }
 if( str.Trim().length > 50 ){
  if(language == 'EN')
  {
   window.alert( "Your member ID should not have more than 50 characters!" );
  }
  else
  {
   window.alert( "您的用户名不能超过50位 ！" );
  }
  return false;
 }
 return chkUserNameFormat( str,language );
 }

function chkUserNameFormat( str,language )
{
 var language = (arguments[1]!='')?arguments[1]:'CN';
 str=str.Trim()
 var regu = "^([a-zA-Z]+[_0-9a-zA-Z@.-]*)$"
 var re = new RegExp(regu);
 if( str.search( re ) != -1 ){
  return true;
 }else{
  if(language == 'EN')
  {
   window.alert( "Please use correct member ID!" );
  }
  else
  {
   window.alert( "请使用规范的用户名！" );
  }
  return false;
 } 
}

function chkNum( value , minvalue , maxvalue ){
 if( isNaN( value ) ){
  return false; 
 }else{
  if( typeof( minvalue ) == 'number' ){
   if( value < minvalue ) {
    return false; 
   }
  }
  if( typeof( maxvalue ) == 'number' ){
   if( value > maxvalue ){
    return false; 
   }
  }
  return true;
 }
}