function isInteger (s)
{   
	var i;

	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;
}

function isInteger(value)
{
	return (parseInt(value) == value);
}

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

function isValidTelephoneNumber(_value)
{
	var _phoneNumberValidCharacters = "1234567890-() ";
	for (var i=0; i < _value.length; i++)
	{
		 if (_phoneNumberValidCharacters.indexOf(_value.charAt(i)) == -1)
		 {
			return false;
		 }
	}
	return true;
}