Closing database connection from destructor

Christopher Yellick

I'm trying to determine if it is acceptable to close the connection to a database in a class' destructor. My understanding is that I have no control over when the destructor is closed, but can I at least be certain that it will be closed by the time the program finishes executing. This is a small desktop application that connects to a local jet database. If it matters, I am using OleDb.

4 Replies

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Vulpes14y ago
Accepted answer
A better idea would be for your class to implement the IDisposable interface. You can then call the Dispose() method to close the database connection or, by wrapping code in a 'using' statement, have this done automatically when the statement ends.

This would ensure that the connection is closed immediately rather than waiting for the garbage collector to get around to calling the destructor.

There is in fact a 'Disposable' pattern you can use where, if you forget to call the Dispose() method, the destructor would close the connection before the object is finally destroyed. Check out:

http://msdn.microsoft.com/en-us/library/system.idisposable.aspx
Senthilkumar14y ago
Hi,

There are many ways to close the database connection. It may be in finally block or destructor or using

But i suggest you to implement this in 'using' block.

using(SqlConnection sqlConnection = new SqlConnection(sqlConnStr))
{

}

The above using block will automatically handle the object release.
Sam Hobbs14y ago
Probably a better soution would be to not keep the connection open for a long time. Close the connection after processing is done if there will be a delay before it is needed again. There are many good reasons for that.

A good way to do that is to use Typed Datasets, and then .Net does it for you. A Typed Dataset would either be a TableAdapter or the Entity Framework. They will handle opening and losing connections automatically.
Christopher Yellick14y ago
Thanks Vulpes, that's exactly what I was looking for.