Hello all,

Have a doubt with releasing objects once I am done with them.

Am developing a Windows Forms MDI database application (Oracle as the backend).

I create various DataReader, DataAdapter, DataSet objects in various child forms (where each child form is a "module" in the application). How and when do I release these objects. Will they be destroyed when the window is closed automatically or do I need to say object.dispose or set them = NULL ?

Example.
I have a "Search for Customers" module which the user invokes from a menu item. This window calls a database procedure which returns a resultset using a refcursor type. Then the search results datagrid is populated using the dataset.

Now the Command, DataSet, DataAdapter types etc I have defined to perform the above, are to be released at what point of time ? Do I need to code it myself or will they be released when the window is closed ?

Basically I wish to know what kind of these database related objects I can reuse in all modules and which objects I will need to create for each child window, so that my application memory requirement is optimum.

I understand this is a very basic query, but I am new to DotNet and my concepts are not quite clear. Will appreciate if you can help clear this query.

Thanks in advance,
yamyam

DataSet: you should clear the DataSet via the .Clear() method if the data is no longer needed.

DataAdapter: you should leave the DataAdapter for Garbage Collection to run its course.

DataReader: you should explicitly close the DataReader via the .Close() method.

.NET's Garbage Collection algorithm is optimized, calling the .Dispose() method on any object creates additional Garbage Collection overhead. Thus; calling .Dispose() should generally be avoided.


- A.Kahtava

So Do i call these methods i.e. DataSet.Clear(), DataReader.Close() etc in the close event of the window, or is there a more appropriate event where I can call them ?

Close them when you are done with them. If they are available to the entire form, and you still need the resource, you could leave it open and close in the form_close event, sure.

Brian

Hi,
I think you can write Exception-Handling Code(try, catch, finally) in your code.
Also, you can clear the objects in finally block.
         Like :
                Dataset.Clear()
                obj=nothing (if any object is declared)
                Connection.CLose()

 DataReader can be closed when you are not using it.

I hope it wud help.

Regards,
Muskaan :)

"Use Exceptions for exceptional problems." - The Pragmatic Prorgammer

Another alternative would be to use a "using" statement.

using ( SqlConnection conn = new SqlConnection() ){ ... }

See the following link for more details: http://weblogs.asp.net/jasonsalas/ar...08/368811.aspx



- A.Kahtava