问题
How do I treat the SQLiteCommand
object,
do I have to call Dispose()
after ExecuteScalar
, ExecuteNonQuery
and ExecuteReader
or not?
The documentation example on SQLiteCommand doesn't dispose it whilst in the SQLiteTransaction the example disposes the SQLiteCommand object.
I always close the data reader object though. My application accesses the db from many threads.
Mostly I am interested in not leaking connections or disturbing SQLite. I am aware of using
and IDisposable
usage
回答1:
It's best-practise to dispose everything that implements IDisposable
as soon as you're finished with it because it might use unmanaged resources.
This should be done with the using-statement since it wraps the code that uses this object and because it disposes it also in case of an exception.
using(var con = new SQLiteConnection(conString))
using(var cmd = new SQLiteCommand(con))
{
con.Open();
// ...
} // also closes the connection
回答2:
If it is disposable, dispose it if you will not use it again. The best would be, to use using
using(SQLiteCommand cmd as new SQLiteCoammand())
{
...
}
So it will be disposed automatically when leaving the using scope.
回答3:
Just do this:
using(var connection = new SqlConnection(ConfigurationManager.ConnectionStrings["MyConn"].ConnectionString))
using(var command = connection.CreateCommand())
{
command.CommandText = "...";
connection.Open();
command.ExecuteNonQuery();
}
Not calling dispose on the command won't do anything too bad. However calling Dispose on it will supress the call to the finalizer, making calling dispose a performance enhancement.
回答4:
The using statement will call Dispose on an object even if an exception occurs that bypasses the code that calls Close(). This way you don't have to write a try/finally block just to close the readers or the connection. You also avoid this 1-in-100 case where you forget to write the proper finally block.
Such 1-in-100 cases have a tendency to occur much more frequently than one would think
来源:https://stackoverflow.com/questions/15408207/do-i-have-to-dispose-the-sqlitecommand-objects