function isEmpty(string) {
    if (string == null || string == "") {
        return true;
     } else {
        return false;
	}
}

function isEmail(string) {
    if (string.search(/^[A-Za-z0-9._%+-]+@[A-Za-z0-9.-]+\.[A-Za-z]{2,4}$/) != -1) {
        return true;
    } else {
        return false;
	}
}

function isAlphabetic(string, bEOK) {
    
    if (isEmpty(string)) {
		if (bEOK) {		
			return true;
		} else {
			return false;
		}
	}
	
	string = string.replace(' ','');
	
	if (string.search(/[a-zA-Z\s\'\.\,\-\&\/\_]*$/)) {
		return false;
	} else {
		return true;
	}
}


function isAlphanumeric(string, bEOK) {
    if (isEmpty(string)) {
		if (bEOK) {		
			return true;
		} else {
			return false;
		}
	}
	
	string = string.replace(' ','');
	
	if (string.search(/[^a-zA-Z0-9\s]/) != -1) {
        return false;
    } else {
        return true;
	}
}


function isAlphanumericNS(string, bEOK) {
   if (isEmpty(string)) {
		if (bEOK) {		
			return true;
		} else {
			return false;
		}
	}
	
	string = string.replace(' ','');
	//alert (string.search(/[^a-zA-Z0-9.]/));
  if (string.search(/[^a-zA-Z0-9.]/) != -1) {
	
        return false;
    } else {
        return true;
	}
}



function isNumeric(string, bEOK) {
    if (isEmpty(string)) {
		if (bEOK) {		
			return true;
		} else {
			return false;
		}
	}
	
	string = string.replace(' ','');
	
	for (i = 0; i < string.length; i++)
	{   
		// Check that current character is number.
		var c = string.charAt(i);

		if (!isDigit(c)) return false;
	}
	
	return true;

}

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


function isZipCode(string, bEOK) {
    if (isEmpty(string)) {
		if (bEOK) {		
			return true;
		} else {
			return false;
		}
	}
	
	if (string.search(/(^\d{5}$)|(^\d{5}-\d{4}$)/)) {
        return false;
    } else {
        return true;
	}
}


function isPhone(string, bEOK) {
    if (isEmpty(string)) {
		if (bEOK) {		
			return true;
		} else {
			return false;
		}
	}
	
	if (string.search(/^\+?[0-9 ()-]+[0-9]$/)) {
        return false;
    } else {
        return true;
	}
}