Book Image

Moodle JavaScript Cookbook

Book Image

Moodle JavaScript Cookbook

Overview of this book

Moodle is the best e-learning solution on the block and is revolutionizing courses on the Web. Using JavaScript in Moodle is very useful to administrators and dynamic developers as it uses built-in libraries to provide the modern and dynamic experience that is expected by web users today.The Moodle JavaScript Cookbook will take you through the basics of combining Moodle with JavaScript and its various libraries and explain how JavaScript can be used along with Moodle. It will explain how to integrate Yahoo! User Interface Library (YUI) with Moodle. YUI will be the main focus of the book, and is the key to implementing modern, dynamic feature-rich interfaces to help your users get a more satisfying and productive Moodle experience. It will enable you to add effects, make forms more responsive, use AJAX and animation, all to create a richer user experience. You will be able to work through a range of YUI features, such as pulling in and displaying information from other websites, enhancing existing UI elements to make users' lives easier, and even how to add animation to your pages for a nice finishing touch.
Table of Contents (15 chapters)
Moodle JavaScript Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface

Adding a field with a minimum length


In this recipe, we will apply a validation constraint which forces the user to enter text of a minimum number of characters. This could be used for cases where a certain number of characters are expected, for example, in a postal code or a telephone number.

Getting ready

Please refer to the first recipe in this chapter for details on how to prepare a QuickForm web form which is the basis of this recipe.

How to do it...

Add the following code to our form definition in validation_form.php just after the field definition:

$mform->addElement('text', 'mytext3', 'Min length 5');
$mform->addRule('mytext3', 'Min length 5', 'minlength', 5, 'client');

Now we can try out this new rule in the web browser. When we enter a string of only four characters, we are unable to submit the form and our warning message is displayed as seen in the following screenshot:

How it works...

We used the validation type minlength which takes a format option in the form of an integer...