how to validate elements other than active elements

how could i validate CHtml::dropdownlist();…which is not a ActiveRecord

Validation is built around model (can be CFormModel, not necessarily CActiveRecord).

no i miss typed it

active elements are validated by writing code in CFormmodel…is there any place there the validation for nonactive elemnts should be kept

nope. You need a model if you want to use the validation provided by Yii.The input field is not necessarily generated by activeXyz.