PHP Forms

This month I look at another of the PEAR packages I find extremely useful - Validate. Poor validation is a key weakness many scripts are guilty of, enabling security exploits. The Validate package can be used to validate any data, and is especially useful for validating user input. It can be used to validate: numbers (whether they fall into a certain range, or are decimal or not) emails (domain, syntax and RFC822) strings (whether they re numeric...

I hate typing, but I like writing code. A while ago I started to dread all the rote typing required to handle forms in PHP, and began looking for a Better Way. This article describes how I used PHP s regular expression functions to do most of the heavy lifting required to process forms properly, saving lots of typing and giving me time to do stuff I don t hate, such as writing code (and playing NetHack). // ); //]] The Problem Jeff Cogswell desc...

One of my most common activities during the development cycle for a Web application involves writing code to validate the data entered into online forms.

Most developers must deal with the job of developing robust data validation for forms on a regular basis. Nobody wants to write the same code over and over, so this article (the first of three in a series) will help you develop an extensible and reusable form validation package. By the end of the article, you will have all the relevant classes that integrate the generator module of the PHP form processor.

In this second part of a three-part series, we take up the topic of server-side validation. By the time you finish this article, you ll have the general guidelines for how to build a form validating class. You ll use some PHP built-in introspection functions, along with regular expressions, to assist you in building this class.

Welcome to the last part of the series Building a PHP 5 form processor. In three parts, this series goes through the development of an extensible form processor package in PHP 5, explaining its benefits and demonstrating its implementation.

Are you looking for an easygoing article that teaches you how to implement the Observer design pattern inside your PHP 5 applications? Your search is finished! Welcome to the last part of the series The Observer Pattern in PHP. Made up of three articles, this series will show you how to create and work with observer objects, without making you scratch your head while looking at complex code samples.

Mastering some of the most popular design patterns with PHP 5 can be sometimes an overwhelming process that requires hard work and experience. However, if you want to tackle the challenge and expand your existing background on them, this article might eventually find a place on your quick reference list.

Are you interested in expanding your existing knowledge of different structural design patterns with PHP 5? Then look no further because you ve come to the right place. Welcome to the second installment of the series Using Bridge Classes with PHP 5. This group of three articles walks you through the basics of how to apply the bridge pattern in PHP-based applications, and it also teaches you how to use bridge objects in real world development en...

Are you interested in expanding your knowledge of creational design patterns and learning how to work with director and builder objects in PHP 5? If your answer is yes, then I think you should start reading this article right now! Welcome to the concluding part of the series How to Use Builder Objects in PHP 5. This series leads you through the application of the builder pattern in PHP, and shows you how to use it with copious hands-on examples...

Want to gain a good grounding in how to apply the Observer pattern in PHP? Then you re in the right place! Welcome to the second part of the series The Observer Pattern in PHP. Composed of three tutorials, this series teaches you the key concepts of the popular Observer design pattern, and shows you how to apply it in the context of real-world PHP applications.

Many applications in the field of Web development need to validate email addresses. While this can be done in a variety of ways, one simple but effective way involves writing your own functions in PHP. Alejandro Gervasio explains this approach.

Every time I ve written some code to upload a file, either to send it off as an email attachment or as an image for some dynamic content piece, I ve always meant to write a few functions so I don t have to write the code again. Well, people on the Back-end.org support board have been asking for the ability to add images to news and articles recently, so I *finally* sat down and wrote this script in order that I can add that functionality to the ...

In the first installment of this occasional series introducing CakePHP, I extolled the virtues of web frameworks by showing you just how CakePHP can automate the implementation of CRUD (Create, Read, Update, and Delete) interfaces. This is a great example of how a framework can greatly decrease development time, because CRUD interfaces are immensely useful no matter what sort of application you re building, are implemented in very much the same ...

The last two installments of this ongoing PHP series focused on the advantages of frameworks, demonstrating just how much time and effort they can eliminate doing otherwise tedious tasks such as building backend management scaffolds and performing forms validation. These tutorials focused on the increasingly popular CakePHP framework, however in this installment I ll switch gears a bit and instead examine my preferred framework solution: symfony...

In the first part of this series, I covered the basics of MVC programming in PHP and created most of the base classes. In Part 2, I will be covering the controller and the presentation layer. (Parts three and four, Implementing the View in PHP MVC and Implementing MVC in PHP: The Model are also available.) // ); //]] The Controller Quite simply, the controller handles incoming requests. It uses input, in this case from the

This article series (starting with Understanding MVC in PHP and continued in Implementing MVC in PHP: The Controller and Implementing MVC in PHP: The View) demonstrates how to build an MVC web framework using PHP 5. This article explains the Model part of Model-View-Controller design. // ); //]] The Model is where the majority of the application s logic sits. It is where you run queries against the database and perform calculat

This is the third article in a series about understanding MVC in PHP. The first article explained basics of MVC programming in PHP. The second article showed the implementation of the Controller in MVC. The final article is Implementing MVC in PHP: The Model. // ); //]] The presentation layer, as I call it, is the View, in common MVC terms. Its sole responsibility is to display information. It could care less about authenticati

Object Oriented Programming (OOP) is a powerful technology for designing Web applications. This article is the first in a three part series that will explain two of the bases of OOP, Inheritance and Polymorphism, and apply these principles to building an extensible form generator.

In part two of this three-part series, we refresh our memory of Inheritance and subclasses from part one, and take our first stab at implementing a form generator.

In the last part of this three-part series of articles, we will find out how to improve the form generator we created in part II by learning about Polymorphism and adding it to the mix.

One of the most common tasks that I came across developing interactive websites was processing users input. In this article I would like to share the experience I had developing an object-oriented solution for it. The best effect that I can imagine this paper to have is to not just show “another solution for checking a submitted form”, but rather to let you taste the power of object-oriented technology. Together with you, I will look b...

If your PHP program is a dynamic web page (and it probably is) and your PHP program is dealing with user input (and it probably is), then you need to work with HTML forms. Here are some tips for simplifying, securing, and organizing your form-handling PHP code. 1. Use $_SERVER[ PHP_SELF ] as a form action. The $_SERVER auto-global array holds various useful server- and request-specific info. The PHP_SELF element of $_SERVER holds the filename of ...

All web developers will at some point need to program their own form. Whether it is for database submission, emailing, or for some other purpose, forms represent the primary means of enabling a user to send data to an application. As a result, it is important to have control over the data collected by your forms, which will aid in the creation of streamlined, error-free applications. Assumptions This article assumes the reader has some prior kno...

In the last exciting episode of the PHP Phanatics, we explored the inner workings of PHP s unique $GLOBALS array. Several sharp-eyed readers pointed out a bug in the script dumping the contents of the $GLOBALS array. If an array element was itself an array, the display listed that fact rather than the contents of the component array. The displayed line looked like: // ); //]] $GLOBALS[HTTP_GET_VARS]=Array In my defense I plead confusion. There w...

When you have publicly available forms on the Web, you are always prone to attack by people who want to use your application for their own purposes. Forums, polls, guestbooks, and blogs are the popular places for robots to try to generate inauthentic posts on your site. Many sites, such as Yahoo, now employ CAPTCHA. CAPTCHA, or completely automated public Turing test to tell computers and humans apart, is a project of the Carnegie Mellon School...

In this final part of the series, Alejandro Gervasio examines a point that he has not taking into consideration so far: that the layout of form elements plays a relevant role within the overall development process. With this in mind, he encapsulates the logic needed to generate web forms by defining a form generator class. This class will implement the form element factory along with all of the required form element classes.

Experienced PHP programmers know that web development problems are often tackled by using widely known design patterns within the context of an application. This article is the first in a series that will demonstrate how the Singleton and Factory patterns can be implemented in a real-world application.

This article series (continued in Implementing MVC in PHP: The Controller, Implementing MVC in PHP: The View, and Implementing MVC in PHP: The Model) demonstrates how to build an MVC web framework using PHP 5. This article covers the basics of MVC web frameworks, building the foundation classes for a framework that the other three articles in this series will build. With the introduction of PHP 5 and its new OOP features developers can now seriou...

One of the more common problems PHP programmers must tackle is that of form data validation. For example, suppose you have a form where users must enter an email address. Using a regular expression, you could test whether the format of the email address is valid before using the email address; if the email address doesn t have a valid format, you can ask the user to re-enter it. Unfortunately, many people code their form tags so that the tag s ac...

Any PHP developer who has worked with pattern-based programming in PHP for a while knows that the abstract factory pattern is useful for building classes that return (to client code) objects whose type depend on the content where they re used. Welcome to the final installment of the series Using abstract factory classes in PHP 5. If you re interested in learning the key concepts of this helpful pattern, this three-part series will tea...

The Internet, as we know it today, is primarily the result of two seminal events: // ); //]] The February 1993 introduction of Mosaic, the first graphical Web browser (see references in the sidebar to the right), and, The 1994 addition of forms to the HTML specification. Mosaic, with its multimedia capability, added entertainment value to what had previously been a bland character-based medium. Forms created the capability for dynamic Web sites ...

Once you know the basics of PHP s syntax and structure, it is fairly easy to make the leap to writing full-fledged scripts. Because working with forms is one the most common tasks in writing applications for the web, the first script we write will be a form processor. Though a fairly mundane application, it will introduce you to a range of important concepts, including how PHP handles variables that come from outside the running script. First, le...

This series has so far focused on XML technologies and how they can be utilised using PHP 5. A subject we have not touched upon yet, is XML validation. This article will explore the application independent XML validation standards of DTD s, the XML Schema Language and the XSLT-based Schematron language. I will demonstrate how to validate XML in PHP and demonstrate how PHP 5 s XSL extension can be used to validate XML using the Schematron language...

Many topics on the discussion forums deal with the verification of form data. Often it is checked to determine whether or not the submission is from a user or from a bot, if the email address entered is a valid address, or if all the information that is required has been entered into the form. While it s fairly easy to check to see if a form field is empty, determining if the posted information came from a real human is another task altogether...

In today s PHP Foundations, I ll begin my introduction of working with HTML forms from PHP. Since there is only time to discuss strictly PHP-related materials, I ll assume that you are already comfortable with HTML and creating HTML forms for user input. If you would like a refresher, there are a number of HTML resources available online. A personal favorite is Sizzling HTML. Getting Form Data Into a PHP Script Assuming that you have already desi...

Welcome back to PHP Foundations. In my previous column, I explained how to retrieve form data with a PHP script via the superglobal arrays ($_GET, $_POST, and $_REQUEST) and the import_request_variables() function. In today s column, I ll be looking at how to accept HTTP file uploads via PHP in a web page. // ); //]] Before showing any code, it is important that I acknowledge that there are a number of PHP configuration directives that affect th...