function validatePosInt()
   {
      var s = document.Add2Basket.quantity.value;
      switch(isPositiveInteger(s))
      {
         case true:
           break;
         case false:
  alert('Antamasi arvo ei kelpaa, tarkista antamasi luku.\n\nValue is not valid, check the quantity.\n\nAntalet duger inte, kontrollera antalet.');
            return false;
      }
   }

   function isPositiveInteger (s)
   {   var secondArg = false;

       if (isPositiveInteger.arguments.length > 1)
          secondArg = isPositiveInteger.arguments[1];

       // The next line is a bit byzantine.  What it means is:
       // a) s must be a signed integer, AND
       // b) one of the following must be true:
       //    i)  s is empty and we are supposed to return true for
       //        empty strings
       //    ii) this is a positive, not negative, number

       return (isSignedInteger(s, secondArg)
          && ( (isEmpty(s) && secondArg)  || (parseInt (s) > 0) ) );
   }


function isSignedInteger (s)

   {   if (isEmpty(s))
      if (isSignedInteger.arguments.length == 1) return false;
      else return (isSignedInteger.arguments[1] == true);

      else {
         var startPos = 0;
         var secondArg = false;

         if (isSignedInteger.arguments.length > 1)
            secondArg = isSignedInteger.arguments[1];

         // skip leading + or -
         if ( (s.charAt(0) == "-") || (s.charAt(0) == "+") )
            startPos = 1;
         return (isInteger(s.substring(startPos, s.length), secondArg))
      }
   }
   
     function validateInt()
   {
      var o = document.frmInput.txtInput;
      switch (isInteger(o.value))
      {
         case true:
            alert(o.value + " is an integer")
            break;
         case false:
            alert(o.value + " is not an integer")
      }
   }

   function validateRange()
   {
      var s = document.frmInput.txtInput.value;
      var A = document.frmInput.txtA.value;
      var B = document.frmInput.txtB.value;

      switch (isIntegerInRange(s, A, B))
      {
         case true:
            alert(s + " is in range from " + A + " to " + B)
            break;
         case false:
            alert(s + " is not in range from " + A + " to " + B)
      }
   }

// isIntegerInRange (STRING s, INTEGER a, INTEGER b)
   function isIntegerInRange (s, a, b)
   {   if (isEmpty(s))
         if (isIntegerInRange.arguments.length == 1) return false;
         else return (isIntegerInRange.arguments[1] == true);

      // Catch non-integer strings to avoid creating a NaN below,
      // which isn't available on JavaScript 1.0 for Windows.
      if (!isInteger(s, false)) return false;

      // Now, explicitly change the type to integer via parseInt
      // so that the comparison code below will work both on
      // JavaScript 1.2 (which typechecks in equality comparisons)
      // and JavaScript 1.1 and before (which doesn't).
      var num = parseInt (s);
      return ((num >= a) && (num <= b));
   }

   function isInteger (s)
   {
      var i;

      if (isEmpty(s))
      if (isInteger.arguments.length == 1) return 0;
      else return (isInteger.arguments[1] == true);

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

         if (!isDigit(c)) return false;
      }

      return true;
   }

   function isEmpty(s)
   {
      return ((s == null) || (s.length == 0))
   }

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