//validate digit strings
function jstype_digit(str) {
	//
	var strValidChars = "0123456789";
	var strChar;
	var blnResult = true;
	//
	if (str.length == 0) return false;
	for (i = 0; i < str.length && blnResult == true; i++) {
		strChar = str.charAt(i);
		if (strValidChars.indexOf(strChar) == -1) {
			blnResult = false;
			}
		}
	return blnResult;
	}

//validate alpha strings
function jstype_alpha(str) {
	//
	var strValidChars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
	var strChar;
	var blnResult = true;
	//
	if (str.length == 0) return false;
	for (i = 0; i < str.length && blnResult == true; i++) {
		strChar = str.charAt(i);
		if (strValidChars.indexOf(strChar) == -1) {
			blnResult = false;
			}
		}
	return blnResult;
	}

//validate alphanumeric strings
function jstype_alnum(str) {
	//
	var strValidChars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
	var strChar;
	var blnResult = true;
	//
	if (str.length == 0) return false;
	for (i = 0; i < str.length && blnResult == true; i++) {
		strChar = str.charAt(i);
		if (strValidChars.indexOf(strChar) == -1) {
			blnResult = false;
			}
		}
	return blnResult;
	}

//validate alphanumeric domain strings; alnum, dash & underscore
function jstype_dom(str) {
	//
	var strValidChars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-_";
	var strChar;
	var blnResult = true;
	//
	if (str.length == 0) return false;
	for (i = 0; i < str.length && blnResult == true; i++) {
		strChar = str.charAt(i);
		if (strValidChars.indexOf(strChar) == -1) {
			blnResult = false;
			}
		}
	return blnResult;
	}

//validate alphanumeric email strings; alnum, dash, underscore, dot, @
function jstype_email(str) {
	//
	var strValidChars = "0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz-_.@";
	var strChar;
	var blnResult = true;
	//
	if (str.length == 0) return false;
	for (i = 0; i < str.length && blnResult == true; i++) {
		strChar = str.charAt(i);
		if (strValidChars.indexOf(strChar) == -1) {
			blnResult = false;
			}
		}
	return blnResult;
	}

//validate sitekno user id
function jstype_stid(str) {
	//
	var blnResult = true;
	//
	if (str.length == 0) return false;
	if ( str.length <= 7 ||
		(str.substring(0,2) != "ST" &&
		 str.substring(0,2) != "St" &&
		 str.substring(0,2) != "sT" &&
		 str.substring(0,2) != "st" ) ||
		!jstype_digit(str.substring(2)) ) {
		blnResult = false;
		}
	return blnResult;
	}