var digits = "0123456789";

function trim(strInput)
{
	var reSpaceStart, reSpaceEnd;
	reSpaceStart = new RegExp("^\\s+", "i");
	reSpaceEnd   = new RegExp("\\s+$", "i");
	return (strInput.toString().replace(reSpaceStart, "")).replace(reSpaceEnd, "");
}

function CheckPhoneNumber(TheNumber)
{
    // non-digit characters which are allowed in phone numbers
    var phoneNumberDelimiters = "()- ";
    // U.S. phone numbers have 10 digits.
    // They are formatted as 123 456 7890 or (123) 456-7890.
    var digitsInUSPhoneNumber = 10;

    var valid = 1;
    var GoodChars = digits + phoneNumberDelimiters;
    var i = 0;
    if (TheNumber=="") {
        // Return false if number is empty
        valid = 0;
    }
    for (i =0; i <= TheNumber.length -1; i++) {
        if (GoodChars.indexOf(TheNumber.charAt(i)) == -1) {
            valid = 0;
        } // End if statement
    } // End for loop
    if (valid != 0)
    {
        var normalizedPhone = stripCharsInBag(TheNumber, phoneNumberDelimiters);
        if (normalizedPhone.length != digitsInUSPhoneNumber)
            valid = 0;
    }
    return valid;
}
// Removes all characters which appear in string bag from string s.
function stripCharsInBag (s, bag)

{   var i;
    var returnString = "";

    // Search through string's characters one by one.
    // If character is not in bag, append to returnString.

    for (i = 0; i < s.length; i++)
    {   
        // Check that current character isn't whitespace.
        var c = s.charAt(i);
        if (bag.indexOf(c) == -1) returnString += c;
    }

    return returnString;
}