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Returning DataReaders

What is the best practise for the following:

I have a client that uses a data access layer to get back a DataReader for binding.

The method sig for this routine is public static OracleDataReader GetReader().

But, I want to embed opening the connection within a try...catch...finally block.

So the method looks like this (pseudo-code-wise):

private OracleDataReader;

try {open conn, populate reader via command object}
catch {catch any errors}

Then return the reader. The problem is, I have to declare the Reader outside the try...catch block but this means I'm trying to return an unassigned variable. Any thoughts on this?

huysmans

Hi,

i guess you equate it to null upon instantiating to avoid the warning.

OracleDataReader reader = null;

cheers,

Paul June A. Domag

Visit my Online Blog - http://webmag.mvps.org

Paul Domag

Slightly on a tangent....

I would advise not to return DataReaders to clients.....DataReaders have an open connection to a database and on the whole this is not something you would want happening in a solution.

Will affect scalability of your app and could lead to all sorts of dramas later on...!

Dylan Morley

Dylan Morley wrote:
Slightly on a tangent....

I would advise not to return DataReaders to clients.....DataReaders have an open connection to a database and on the whole this is not something you would want happening in a solution.

Will affect scalability of your app and could lead to all sorts of dramas later on...!

Good point, what would you return instead? Populate a dataset/business object, close the connection and return that?

huysmans

Yeah thats it......anything other than DataReader!

Personally, I like the business object approach....find it makes the GUI code very clean & explicit....gives you a lot of control over the object.

DataSets are fine, but I tend to use them more more ad-hoc stuff like reports etc.

Dylan Morley

reply 5

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