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What is Yav?

Yav is a SIMPLE, POWERFUL and CUSTOMIZABLE javascript-based form validation tool. (yav is a javascript form validator)

Below is a list of most important features:

  • Many different validation rules
  • onblur notification of errors
  • Advanced pre-condition and post-condition rules
  • Extendible and flexible: user can create his own validation rules
  • onfocus auto-help
  • Notification of errors classic and advanced, yet customizable
  • Ajax support
  • Cross-browser compatibility
  • Only 17kb without external dependencies

Yav is licensed under the LGPL license, therefore you can use it in both commercial and open-source projects.

Yav is hosted on SourceForge and we have our discussion group where you may post questions, bug reports, ideas, feature requests, etc... Your feedback is important to improve this tool.

Yav is a free license software, but any free donations are welcome!

Support This Project

Yav 2.0 update (1 April 2008)

Welsh translation is available (thank's to Alan Davies).

Yav 2.0 available (15 March 2008)

New features:

new: onblur notification of errors.
new: onfocus auto-help, you can tell the user what's expected of him for each field.
new: you can define your input masks (check the maximum field length and the characters allowed, and separators are automatically added).
new: pre-validation and post-validation (ajax support).
new: custom rules have a new syntax, so inline notifications and highlight work fine (back compatibility maintained).
new: yav now uses two namespaces, yav and yav_config (keeping down potential naming collisions).
new: unobtrusive javascript: yav separates javascript from html.