form textfield validation?

Yii 1.1 General Discussion
1

How can i validate a form for the input is not bigger than 36 and error message?

2

http://www.yiiframework.com/doc/api/1.1/CModel#rules-detail

http://www.yiiframework.com/doc/api/1.1/CActiveForm#textField-detail

and Finally

http://www.yiiframework.com/doc/api/1.1/CActiveForm#error-detail