Using HTML_QuickForm To Manage Web Forms, Part 1 - Password Field Validation
(Page 11 of 13 )
Note that I have added some text field to my Web form to demonstrate another common validation requirement - the comparison of text entered in two "password" fields.
<?php
// snip
$obj_registration_form->addElement('text', 'txtUsername', 'Username:', array( 'size' => 40, 'maxlength' => 15));
$obj_registration_form->addElement('password', 'txtPassword1', 'Password:', array( 'size' => 40, 'maxlength' => 15));
$obj_registration_form->addElement('password', 'txtPassword2', 'Re-enter Password:', array( 'size' => 40, 'maxlength' => 15));
// snip
$obj_registration_form->addRule('txtPassword1', 'Please enter your "Password" as it is a required field.', 'required');
$obj_registration_form->addRule(array('txtPassword1', 'txtPassword2'), 'The two passwords do not match. Please re-enter your password correctly.', 'compare');
$obj_registration_form->addRule('txtPassword1', 'Please enter a valid "Password" containing between 8 and 10 consisting of alphabets and numbers only.', 'regex', '/^[a-zA-Z0-9]{8,10}$/');
// snip
?>
Here, I have added three new text fields: one for the user to enter his/ her username and two password fields to ensure that the user enters the password correctly. This is a common feature for most Web forms.
Next, I would like to highlight the "compare" keyword. This new rule allows me to compare the values entered into any two text fields. All I need to do is pass the names of the two controls to the addRule() method.
Here is the error message displayed on the screen if the user enters two different values in the "Password" and "Confirm Password" fields.
The above example has implemented server-side validation for all the fields of the Web form. However, it is also possible to implement client-side with a little modification to the above example:
Code Listing 4
Load this example in your browser and click the "Register" button with filling any form field. The browser will immediately throw a JavaScript alert as seen below:
This client-side validation is, courtesy of, a simple update to each validation rule defined in our earlier script:
<?php
// snip
// validation rules come here
$obj_registration_form->addRule('txtAddress', 'Please enter your "Address" as it is a required field.', 'required', null, 'client');
$obj_registration_form->addRule('txtAddress', 'Please enter at least 20 characters in the "Address" field.', 'minlength', 20, 'client');
$obj_registration_form->addRule('txtAddress', 'Please enter at most 255 characters in the "Address" field.', 'maxlength', 255, 'client');
// snip
?>
The fifth parameter of the addRule() method is used to specify the location where I wish to check the validations. This parameter takes two values: the first is "server" - the default value - and the second is "client."
A little point to keep in mind: server-side is always performed. This ensures that validations are still implemented if a user has turned off JavaScript in his/her browser.
So far, this class has met my requirements as defined at the beginning of this article. Now, all that remains to be seen is how to store the data submitted by the user into a database, which is the final step for most Web form applications.
Next: Processing Data With HTML_QuickForm >>
More Design Usability Articles
More By Harish Kamath
