function isWhiteSpace(c)
{
	return (c == ' ');
}

function isDigit(c)
{
	return ((c >= '0') && (c <= '9'));
}

function trim(str)
{
  if(str == null)
  {
    return str;
  }

  var strLen = str.length;
  if(strLen ==  0)
  {
    return str;
  }

  var startIndex = -1;
  var endIndex;
  var newStr;

  for(var i = 0; i < strLen; i++) 
  {
    if(!isWhiteSpace(str.charAt(i))) 
    {
      startIndex = i;
      break;
    }
  }

  if(startIndex == -1)
  {
    return "";
  }

  for(var i = strLen - 1; i >= startIndex; i--) 
  {
    if(!isWhiteSpace(str.charAt(i))) 
    {
      endIndex = i;
      break;
    }
  }

  newStr = str.substring(startIndex, endIndex + 1);

  return newStr;
}

function isEmpty(str)
{
  if(str == null)
  {
    return true;
  }

  var strLen = str.length;
  if(strLen == 0)
  {
    return true;
  }

  for(var i = 0; i < strLen; i++) 
  {
    if(!isWhiteSpace(str.charAt(i)))
    {
      return false;
    }
  }
  return true;
}

function isusername (s)
{
         var regu = "^([a-zA-Z]+[_0-9a-zA-Z@.-]*)$"
         var re = new RegExp(regu);
         if (s.search(re) != -1) {
               return true;
         } else {
               //window.alert ("请按照提示要求输入用户名！")
               return false;
         }
}

function isemail (s)
{
        if (s.length > 100)
        {
                //window.alert("email地址长度不能超过100位!");
                return false;
        }
		s = s.toLowerCase()
		 var regu = "^(([0-9a-zA-Z]+)|([0-9a-zA-Z]+[_.0-9a-zA-Z-]*))@([a-zA-Z0-9-]+[.])+([a-zA-Z]{2}|net|NET|com|COM|gov|GOV|mil|MIL|org|ORG|edu|EDU|int|INT|name|NAME)$";
		 var re = new RegExp(regu);
         if (s.search(re) != -1) {
               return true;
         } else {
               //window.alert ("请输入有效合法的E-mail地址 ！");
               return false;
         }
}

function Jtrim(str)
{

        var i = 0;
        var len = str.length;
        if ( str == "" ) return( str );
        j = len -1;
        flagbegin = true;
        flagend = true;
        while (( flagbegin == true) && (i< len))
        {
           if ( str.charAt(i) == " " )
                {
                  i=i+1;
                  flagbegin=true;
                }
                else
                {
                        flagbegin=false;
                }
        }

        while  ((flagend== true) && (j>=0))
        {
            if (str.charAt(j)==" ")
                {
                        j=j-1;
                        flagend=true;
                }
                else
                {
                        flagend=false;
                }
        }

        if ( i > j ) return ("");

        trimstr = str.substring(i,j+1);
        return trimstr;
}