Need to close DataReader?



If it need to close DataReader after read?
I am study the Data Access Application Block for .Net Framework2.0 form
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dnpag2/html/entlibjan2006_dataaccessappblock.asp

I found the the DataReaders in the examples are not close explicitly in
program.

Dose it need to close DataReader after read?


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