/*************************************************************************\
boolean isInteger(String argvalue)
return true if argvalue is a valid integer,
else return false.
\*************************************************************************/

function isInteger(argvalue) {
	argvalue = argvalue.toString();
	
	if (argvalue.length == 0)
	return false;
	
	for (var n = 0; n < argvalue.length; n++) {
		var oneChar = argvalue.charAt(n);
		if ( n == 0 && (oneChar == "+" || oneChar ==
		"-")) continue;
		if (oneChar < "0" || oneChar >
		"9")
		return false;
	}
	return true;
}