<!-- The roommate application makes use of client side javascripts for performing user -->

var decimalPointDelimiter = ".";

function isEmail (String)
{  
	  var i = 1 ;
	  var sLength = String.length ;
	  while ((i < sLength) && (String.charAt(i) != "@")) i++ ;
	  if ((i >= sLength) || (String.charAt(i) != "@")) return false ;
	  else i += 2 ;
	  while ((i < sLength) && (String.charAt(i) != ".")) i++ ;
	  if ((i >= sLength - 1) || (String.charAt(i) != ".")) return false ;
	  else return true ;
 }

 
function Trim (String)
{
  var start = 0 ;

  var end = String.length - 1 ;
  
  while (start < end && String.charAt(start) == " ") start++ ;

  while (end >= 0 && String.charAt(end) == " ") end-- ; 

  if (end < start) return "" ;

  return String.substring(start, end-start+1) ;
}

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


function isNumeric (String)
{	var i;
	var seenDecimalPoint = false;
	
    if (Trim(String) == "") return false; 

    if (String == decimalPointDelimiter) return false;

    for (i = 0; i < String.length; i++)
    {   var c = String.charAt(i);

        if ((c == decimalPointDelimiter) && !seenDecimalPoint) seenDecimalPoint = true;
        else if (!isDigit(c)) return false;
    }

    return true;
}

function isAlphabetic (s, required)
{	if (required == true){
		if (Trim(s) == "") return false;
	}
	else{
		if (Trim(s) == "") return true;
	}
	
	for (var i = 0; i < s.length; i++)
	{   
		var c = s.charAt(i);
		
		if (!(((c >= "a") && (c <= "z")) || ((c >= "A") && (c <= "Z")) || (c == "_") || (c == "-") || isDigit(c)))
			return false;
	}
		
	return true;
}