//------------------------------------------------------------------------
// LTrim()
// ===================
//------------------------------------------------------------------------
function LTrim(strVal) {
	for (var i=0; (i<=strVal.length); i++){
		if (strVal.charAt(i)!=" "){
			break
		}
	}
	return strVal.substr(i)
}

//------------------------------------------------------------------------
// RTrim()
// ===================
//------------------------------------------------------------------------
function RTrim(strVal) {
	for (var i=(strVal.length-1); (i>=0); i--){
		if (strVal.charAt(i)!=" "){
			break
		}
	}
	return strVal.substr(0,i+1)
}

//------------------------------------------------------------------------
// AllTrim()
// ===================
//------------------------------------------------------------------------
function AllTrim(strVal) {
	return LTrim(RTrim(strVal))
}

//------------------------------------------------------------------------
// selectCheckBox()
// ===================
//------------------------------------------------------------------------
function selectCheckBox(oCheckbox,bSelectAll){
	for (i=0;i < oCheckbox.length; i++){
		oCheckbox[i].checked = bSelectAll;
	}
}

//------------------------------------------------------------------------
// validateCreditCard()
// ===================
//------------------------------------------------------------------------
function validateCreditCard(object_value){

	var white_space = " -";
	var creditcard_string="";
	var check_char;


    if (object_value.length == 0)
        return true;

	// squish out the white space
	for (var i = 0; i < object_value.length; i++)
	{
		check_char = white_space.indexOf(object_value.charAt(i))
		if (check_char < 0)
			creditcard_string += object_value.substring(i, (i + 1));
	}	

	// if all white space return error
    if (creditcard_string.length == 0)
        return false;
	 
	 	
	// make sure number is a valid integer
	if (creditcard_string.charAt(0) == "+")
        return false;

	if (!validateInteger(creditcard_string))
		return false;

    // now check mod10

	var doubledigit = creditcard_string.length % 2 == 1 ? false : true;
	var checkdigit = 0;
	var tempdigit;

	for (var i = 0; i < creditcard_string.length; i++)
	{
		tempdigit = eval(creditcard_string.charAt(i))

		if (doubledigit)
		{
			tempdigit *= 2;
			checkdigit += (tempdigit % 10);

			if ((tempdigit / 10) >= 1.0)
			{
				checkdigit++;
			}

			doubledigit = false;
		}
		else
		{
			checkdigit += tempdigit;
			doubledigit = true;
		}
	}	

	return (checkdigit % 10) == 0 ? true : false;

}

//------------------------------------------------------------------------
// validateInteger()
// ===================
//------------------------------------------------------------------------
function validateInteger(object_value)
    {
    //Returns true if value is a number or is NULL
    //otherwise returns false	

    if (object_value.length == 0)
        return true;

    //Returns true if value is an integer defined as
    //   having an optional leading + or -.
    //   otherwise containing only the characters 0-9.
	var decimal_format = ".";
	var check_char;

    //The first character can be + -  blank or a digit.
	check_char = object_value.indexOf(decimal_format)
    //Was it a decimal?
    if (check_char < 1)
		return validateNumber(object_value);
    else
		return false;
	
}

//------------------------------------------------------------------------
// validateNumber()
// ===================
//------------------------------------------------------------------------
function validateNumber(object_value)
    {
    //Returns true if value is a number or is NULL
    //otherwise returns false	

    if (object_value.length == 0)
        return true;

    //Returns true if value is a number defined as
    //   having an optional leading + or -.
    //   having at most 1 decimal point.
    //   otherwise containing only the characters 0-9.
	var start_format = " .+-0123456789";
	var number_format = " .0123456789";
	var check_char;
	var decimal = false;
	var trailing_blank = false;
	var digits = false;

    //The first character can be + - .  blank or a digit.
	check_char = start_format.indexOf(object_value.charAt(0))
    //Was it a decimal?
	if (check_char == 1)
	    decimal = true;
	else if (check_char < 1)
		return false;
        
	//Remaining characters can be only . or a digit, but only one decimal.
	for (var i = 1; i < object_value.length; i++)
	{
		check_char = number_format.indexOf(object_value.charAt(i))
		if (check_char < 0)
			return false;
		else if (check_char == 1)
		{
			if (decimal)		// Second decimal.
				return false;
			else
				decimal = true;
		}
		else if (check_char == 0)
		{
			if (decimal || digits)	
				trailing_blank = true;
        // ignore leading blanks

		}
	        else if (trailing_blank)
			return false;
		else
			digits = true;
	}	
    //All tests passed, so...
    return true
    }