Exception handling????

[alex_read]

Hi people! At the moment, I use this type of routine in VB:

Sub Test()
    Dim obj as Object 
 
    Try
        ' obj.new
        ' obj.property
    Catch ex as Exception 
        ' handle obj exception
    Finally
        If not (obj is nothing) then
            obj = nothing
        End If
    End Try
End Sub

From doing the same in this c# language, this:

void Test() {
    object obj

    try {
        // obj.new
        // obj.property
    }
    catch Exception ex {
        // handle obj exception
    }    
    finally {
        if (obj !=null) {
            obj = null
        }
    }
}

Generates a "Use of unassigned local variable" exception for the obj variable. It looks like my choices are:

1) To declare and set with the New() keyword, any objects, right at the top of the method - which means a performance hit as I'm not just referencing them only when I need to, or...

2) To put the calls to set the object to null within only the try block. Then if an exception's generated before this line, just leave it to the garbage collector only to clear the object from memory.

Surely this can't be right can it? I though C# was at least the same, if not more efficient than VB?

[jmcilhinney]

Simply assign "null" to your variable and you'll have no issues, i.e. object obj = null;

Edit:
Be aware, though, that setting your object reference to null in the Finally block is still leaving things to the garbage collector. You are not actually disposing your object but simply removing all references to it. This just tells the garbage collector that it can clean up your object whenever it is ready. Unless your object doesn't go out of scope for some time after this section of code setting your variable to null does not really achieve anything, although it may still be good practice. If you want to free the resources held by your object you need to explicitly dispose it before setting your reference to null.