Handling Form Errors in PHP

Since most of web development revolves around form processing i made this crude Error handling class a while back. Its very simple containing

1. isEmpty
2. isValidLength
3. isNumerical
4. isAlpha …and more. enjoy.

/***************************
 * Name: Error.class.php
 * Description: Handles error checking and reporting
 * throught out the site.
 ****************************/

 class Error {

 	var $message;

	/**********************
	 * CONSTTRUCTOR
	 **********************/
	function Error(){}

    /**********************
	 * DESTRUCTOR
	 **********************/
	function __destruct(){}

	function getMessage(){
		return $this->message;
	}

	/************************
	 * IsEmpty:
	 * Description: Checks if the parameters is empty
	 * Parameters:  (String) Parameter Name | (String) Parameter Values
	 ************************/
	function isEmpty($parameterName, $parameterValue){

		$parameterValue = trim($parameterValue);
		if(empty($parameterValue)){

			$this->message = "The ".$parameterName." field can not be empty.";
			return true;

		}else{
			return false;
		}

	}//End isEmpty

	/************************
	 * isValidLength:
	 * Description:   Checks if the value is proper length.
	 * Parameters:    (String) Parameter Name | (String) Parameter Values | (Int) Max Length
	 ************************/
	function isValidLength($parameterName, $parameterValue, $maxLength){

		if(strlen($parameterValue) > $maxLength){
			$this->message = "The ".$parameterName." value is longer than the allowed size.";
			return false;
		}else{
			return true;
		}

	}//End isValidLength

	/************************
	 * isNumerical:
	 * Description:   Checks if the value is only numerical digits
	 * Parameters:    (String) Parameter Name | (String) Parameter Values
	 ************************/
	function isNumerical($parameterName, $parameterValue){

		if(!is_numeric($parameterValue)){

			$this->message = "The ".$parameterName." field contains non-numeric illegal characters";
			return false;

		}else{
			return true;
		}

	}//End isNumerical

	/************************
	 * isAlpha:
	 * Description:   Checks if the value contains only letters
	 * Parameters:    (String) Parameter Name | (String) Parameter Values
	 ************************/
	function isAlpha($parameterName, $parameterValue){

		if(!preg_match("/[A-Z]*/i", $parameterValue)){

			$this->message = "The ".$parameterName." field contains non-alpha illegal characters.";
			return false;

		}else{

			return true;
		}

	}

	/************************
	 * isValidString:
	 * Description:   Generic Validator - checks that the value does not contain invalid characters
	 * Parameters:    (Array) Array of invalid characters | (String) Parameter Value
	 ************************/
	function isValidString($parameterName, $parameterValue, $format){

		if(!preg_match("/".$format."/i", $parameterValue)){
			$this->message = "The ".$parameterName." field contains illegal characters.";
			return false;
		}else{
			return true;
		}

	}//End isValidString

	/************************
	 * isFormat:
	 * Description:   Check is the string has th4e right format
	 * Parameters:    (String) Reg Ex | (String) Parameter Value
	 ************************/
	function isFormat($parameterName, $parameterValue, $format){

		if(!eregi($format, $parameterValue)){
			$this->message = "The ".$parameterName." field contains a wrong formated value.";
			return false;
		}else{
			return true;
		}

	}//End isFormat

 }//End class
 ?>

Armando Padilla