//Please note that these scripts require
//the following files or the function(s) included in them
//(on file per comment line)
//function isDigit.js
//function isEmpty.js

//if this variable is not defined somewhere else
//remove the comment marks or define it on the HTML page

var defaultEmptyOK = false;

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

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

function isInteger (s)
{   
	var i;

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

    // Search through string's characters one by one
    // until we find a non-numeric character.
    // When we do, return false; if we don't, return true.

    for (i = 0; i < s.length; i++)
    {   
        // Check that current character is number.
        var c = s.charAt(i);

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

    // All characters are numbers.
    return true;
}