i have requirement that  i have to read xml data for specific id. for example  i want to  
  retrieve all district names in   id:21. can any one please help me
   
    <?xml version="1.0" encoding="utf-8" ?>
    <Rnames>
    <org id="19">
    <District name="District 19A1"/>
    <District name="District 19A2"/>
    <District name="District 19A3"/>
    <District name="District 19A4"/>
    </org>
    <org id="20">
    <District name="District 20A1"/>
    <District name="District 20A2"/>
    </org>
    <org id="21">
    <District name="District 21A1"/>
    <District name="District 21A2"/>
    <District name="District 21A3"/>
    <District name="District 21A4"/>
    </org>
    <org id="22">
    <District name="District 22A1"/>
    <District name="District 22A2"/>
    </org>
    <org id="23">
    <District name="District 23A1"/>
    <District name="District 23A2"/>
    </org>
    </Rnames>