The HTML pattern attribute - regular expressions on input fields

In this post we take a look at the new "pattern" attribute in HTML which allows you to add custom validation to your input fields through the form of a regular expression pattern.

So for beginners to set the record straight it is possible to validate form input fields using html.The most common attribute that you may be familiar with is the required attribute.

So what does required attribute do?

The required attribute makes the input field compulsory,so the user can't submit form data without filling the input field required.

Common Attribute Usage



<input type="text" placeholder="username" required>


HTML "pattern" attribute

In our example below we are validating the username input field.Here we check if the Username is between 5 to 10 in length.



<input type="text" pattern="[A-Za-z\d]{5,10}" title="Username should be between 5 to 10 in length and contain atleast a number" required>

<input type="submit">


Example Explained

Let's look at each part in this pattern attribute pattern="[A-Za-z\d]{5,10}"

A-Za-z - This indicates that both Uppercase and Lowercase letters are allowed.

\d - This indicates that the username should atleast contain a nubmber.

{5,10} - This specifies the minimum - maximum length of the username.It is user defined so you can set your own limit.

collections_bookmark Category :: Html
date_range Published :: 9 months ago At: 03:23 AM
person Writer :: Code