function trim(str)

{

tstr=""

      for (i=0;i<str.length;i++)

      {

            if (str.charAt(i) != " ")

            {

                 tstr= tstr + str.charAt(i); 

            }

      }

 

return tstr;

}

 

function isEmail (s)

{ 

  

  if (isEmpty(s)) 

      return true; 

      var i = 1;

    var sLength = s.length;

   

    while ((i < sLength) && (s.charAt(i) != "@"))

    { i++;

    }

    if ((i >= sLength) || (s.charAt(i) != "@")) return false;

    else i += 2;

  

    while ((i < sLength) && (s.charAt(i) != "."))

    { i++

    }

    

    if ((i >= sLength - 1) || (s.charAt(i) != ".")) return false;

    else return true;

}

 

function isEmpty(s)

{   return ((s == null) || (s.length == 0))

}

 

 

function isInteger (s)

 

{   var i;

 

    

    for (i = 0; i < s.length; i++)

    {   

        var c = s.charAt(i);

 

        if (!isDigit(c)) return false;

    }

 

    return true; 

}

 

function isDigit (c)

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

}

 

function isDate(dtStr)

{

  var l,i;

  if (dtStr == "")

  return true;

  l=dtStr.length;

  var pos1=dtStr.indexOf("/")

  var pos2=dtStr.indexOf("/",pos1+1)

  var strDay=dtStr.substring(0,pos1)

  var strMonth=dtStr.substring(pos1+1,pos2)

  var strYear=dtStr.substring(pos2+1)

  if (strDay.length > 1)

  {

     if ( strDay.charAt(0)== "0" )

     strDay=strDay.substring(1,strDay.length);

  }

  if (strMonth.length > 1)

  {

     if ( strMonth.charAt(0) == "0" )

     strMonth=strMonth.substring(1,strMonth.length);

  }

  if (strYear.length > 1)

  {

     if ( strYear.charAt(0) == "0" )

     strYear=strYear.substring(1,strYear.length);

  }

  

  if (pos1==-1 || pos2==-1)

  {

      alert("The date format should be : dd/mm/yyyy")

      return false

  }

  if (isInteger(strDay) == false)

  {

     alert("Day must be numeric")

     return false

  }

  if (isInteger(strMonth) == false)

  {

     alert("Month must be numeric")

     return false

  }

  if (isInteger(strYear) == false)

  {

     alert("Year must be numeric")

     return false

  }

  var month=parseInt(strMonth)

  var day=parseInt(strDay)

  var year=parseInt(strYear)

  if (strYear.length != 4 || year==0 || year<1900 || year>9999)

  {

            alert("Please enter a valid 4 digit year between 1900 and 9999")

            return false

  }

  if (month < 1 || month > 12)

  {

        alert("Please enter a valid month")

            return false

  }

  if (day<1 || day>31)

  {

            alert("Please enter a valid day")

            return false

  }

  if (month == 2 && day >28 )

  {

    dayf=(((year % 4 == 0) && ( (!(year % 100 == 0)) || (year % 400 == 0))) ? 29 : 28 )

    if (day != dayf)

    {

      alert("Please enter a valid day")

        return false

      }

  }

  

   return true

}

function isSpace (s)

{ 

  

  if (isEmpty(s)) 

      return true; 

    var i = 0;

    var sLength = s.length;

    var count = 0 ;

    while (i < sLength)
    {
	if(s.charAt(i) == " " )
		count++;
    	 i++;

    }
    

    if (count>0) return false;

    else return true;

}