Rejecting punctuation characters

In this recipe, we will add a rule that prevents the input of punctuation characters. This could be useful, for example, where you require the title of a new document to not contain periods or commas.

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', 'mytext10', 'No punctuation');
$mform->addRule('mytext10', 'No punctuation', 'nopunctuation', null, 'client');

When we test this new rule by entering text that includes punctuation characters (a comma or period), we see that the warning message is displayed and we are unable to submit the form as seen in the following screenshot:

How it works...

We used the validation type nopunctuation which does not require any format options. When a user enters text including any punctuation...