Creating Custom HTML5 Input Types Using Regular Expressions | Web Builder Zone
HTML5 introduces a `pattern` attribute for text input fields that allows developers to validate user input against regular expressions directly in markup, eliminating the need for JavaScript onblur event handlers used in previous HTML versions. The pattern value must follow JavaScript regular expression syntax and will match against the entire input value, with optional `title` attributes providing user-friendly error messages when validation fails. For browsers lacking native support, Google's Web Forms 2 library provides cross-browser compatibility by automatically implementing HTML5 form features when needed.