Compiler warning: null reference exception

Question

I have the following code in Visual Studio 2005.

    Dim OutFile As System.IO.StreamWriter
    Try
        OutFile = New System.IO.StreamWriter(Filename)
       // Do stuff with OutFile
    Catch Ex As Exception
       // Handle Exception
    Finally
       If OutFile IsNot Nothing Then OutFile.Close()
    End Try

But VS2005 brings up the warning for the line "If OutFile IsNot.." that

Variable 'OutFile' is used before it has been assigned a value. A null reference exception could result at runtime.

Is there some way of removing this warning by subtly altering the code or is there just a better way of doing what I'm trying to do?

Thanks

Rob

Answer 1

Dim OutFile As System.IO.StreamWriter
OutFile = Nothing
Try
    OutFile = New System.IO.StreamWriter(Filename)
   // Do stuff with OutFile
Catch Ex As Exception
   // Handle Exception
Finally
   If OutFile IsNot Nothing Then OutFile.Close()
End Try

Similar to http://stackoverflow.com/questions/256073/c-error-use-of-unassigned-local-variable#256078

Answer 2

Its a question of scope, the initialisation of the outfile object is happening in a block of code not visible to the fianlly block.