Demo: http://jquery.bassistance.de/validate/demo/
hoặc: http://docs.jquery.com/Plugins/Validation
Download: http://bassistance.de/jquery-plugins/jquery-plugin-validation/
Giả sử có 1 form như sau:
<form class="cmxform" id="commentForm" method="get" action="">
<fieldset>
<legend>A simple comment form with submit validation and default messages</legend>
<p>
<label for="cname">Name</label>
<em>*</em><input id="cname" name="name" size="25" class="required" minlength="2" />
</p>
<p>
<label for="cemail">E-Mail</label>
<em>*</em><input id="cemail" name="email" size="25" class="required email" />
</p>
<p>
<label for="curl">URL</label>
<em> </em><input id="curl" name="url" size="25" class="url" value="" />
</p>
<p>
<label for="ccomment">Your comment</label>
<em>*</em><textarea id="ccomment" name="comment" cols="22" class="required"></textarea>
</p>
<p>
<input class="submit" type="submit" value="Submit"/>
</p>
</fieldset>
</form>
%3Cform%20class%3D%22cmxform%22%20id%3D%22commentForm%22%20method%3D%22get%22%20action%3D%22%22%3E%0A%20%3Cfieldset%3E%0A%20%20%20%3Clegend%3EA%20simple%20comment%20form%20with%20submit%20validation%20and%20default%20messages%3C%2Flegend%3E%0A%20%20%20%3Cp%3E%0A%20%20%20%20%20%3Clabel%20for%3D%22cname%22%3EName%3C%2Flabel%3E%0A%20%20%20%20%20%3Cem%3E%2A%3C%2Fem%3E%3Cinput%20id%3D%22cname%22%20name%3D%22name%22%20size%3D%2225%22%20class%3D%22required%22%20minlength%3D%222%22%20%2F%3E%0A%20%20%20%3C%2Fp%3E%0A%20%20%20%3Cp%3E%0A%20%20%20%20%20%3Clabel%20for%3D%22cemail%22%3EE-Mail%3C%2Flabel%3E%0A%20%20%20%20%20%3Cem%3E%2A%3C%2Fem%3E%3Cinput%20id%3D%22cemail%22%20name%3D%22email%22%20size%3D%2225%22%20%20class%3D%22required%20email%22%20%2F%3E%0A%20%20%20%3C%2Fp%3E%0A%20%20%20%3Cp%3E%0A%20%20%20%20%20%3Clabel%20for%3D%22curl%22%3EURL%3C%2Flabel%3E%0A%20%20%20%20%20%3Cem%3E%20%20%3C%2Fem%3E%3Cinput%20id%3D%22curl%22%20name%3D%22url%22%20size%3D%2225%22%20%20class%3D%22url%22%20value%3D%22%22%20%2F%3E%0A%20%20%20%3C%2Fp%3E%0A%20%20%20%3Cp%3E%0A%20%20%20%20%20%3Clabel%20for%3D%22ccomment%22%3EYour%20comment%3C%2Flabel%3E%0A%20%20%20%20%20%3Cem%3E%2A%3C%2Fem%3E%3Ctextarea%20id%3D%22ccomment%22%20name%3D%22comment%22%20cols%3D%2222%22%20%20class%3D%22required%22%3E%3C%2Ftextarea%3E%0A%20%20%20%3C%2Fp%3E%0A%20%20%20%3Cp%3E%0A%20%20%20%20%20%3Cinput%20class%3D%22submit%22%20type%3D%22submit%22%20value%3D%22Submit%22%2F%3E%0A%20%20%20%3C%2Fp%3E%0A%20%3C%2Ffieldset%3E%0A%20%3C%2Fform%3E
Để kiểm tra form cách đơn giản nhất là:
<script>
$(document).ready(function(){
$("#commentForm").validate();
});
</script>
%20%20%3Cscript%3E%0A%20%20%24%28document%29.ready%28function%28%29%7B%0A%20%20%20%20%24%28%22%23commentForm%22%29.validate%28%29%3B%0A%20%20%7D%29%3B%0A%20%20%3C%2Fscript%3E