How to build HTML pattern Attribute in input - HTML Input Attributes

The input pattern attribute specifies a regular expression that the input field's value is checked against, when the form is submitted.

The pattern attribute works with the following input types: text, date, search, url, tel, email, and password.

Tip: Use the global title attribute to describe the pattern to help the user.

Tip: Learn more about regular expressions in our JavaScript tutorial.

How to look HTML pattern Attribute in input

An input field that can contain only three letters (no numbers or special characters):

index.html

Example: HTML

 <form>
  <label for="country_code">Country code:</label>
  <input type="text" id="country_code" name="country_code"
  pattern="[A-Za-z]{3}" title="Three letter country code">
</form>

Output should be:

Full Example of HTML pattern Attribute in input

The pattern attribute specifies a regular expression that the input element's value is checked against.

index.html

Example: HTML

<!DOCTYPE html>
<html>
<body>

<h1>The input pattern attribute</h1>

<p>The pattern attribute specifies a regular expression that the input element's value is checked against.</p>

<form action="/action_page.php">
  <label for="country_code">Country code:</label>
  <input type="text" id="country_code" name="country_code" pattern="[A-Za-z]{3}" title="Three letter country code"><br><br>
  <input type="submit" value="Submit">
</form>

</body>
</html>

Output should be:

Category:	Web Tutorial
Sub Category:	HTML Input Attributes
Uploaded by:	Admin

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