declare DIM within TRY statement

[wk6pack]

Hi,

I was wondering why when I declare the dim variable outside the try
statement, I could use the .dispose() function but when I declare it inside
the try statement, I get Name 'varname' is not declared.

thanks,
Will

 

[Jay B. Harlow [MVP - Outlook]]

Will,
It has to do with variable scope.

If you use:

Dim x As IDisposable
Try
Finally
x.Dispose
End Try

The x variable is at the same scope as the Try itself.

However if you do:

Try
Dim y As IDisposable
Finally
y.Dispose
End Try

The y variable is in the Try's block scope.

Remember that most block statements in VB.NET introduces a new block scope,
allowing each scope to define the same variable.

For details on Scope in VB.NET see:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vbcn7/html/vbconScope.asp

Hope this helps
Jay

 

[Jon Skeet [C# MVP]]

I was wondering why when I declare the dim variable outside the try
statement, I could use the .dispose() function but when I declare it inside
the try statement, I get Name 'varname' is not declared.

Where are you trying to use it? In the finally block? If so, that's the
problem - the scope of the try block is just the try block, and with
good reason: the code execution might not have even reached the place
where your variable is declared before an exception is thrown.

 

[wk6pack]

thanks for the explanation and reference.

Will

Will,
It has to do with variable scope.

If you use:

Dim x As IDisposable
Try
Finally
x.Dispose
End Try

The x variable is at the same scope as the Try itself.

However if you do:

Try
Dim y As IDisposable
Finally
y.Dispose
End Try

The y variable is in the Try's block scope.

Remember that most block statements in VB.NET introduces a new block scope,
allowing each scope to define the same variable.

For details on Scope in VB.NET see:

http://msdn.microsoft.com/library/default.asp?url=/library/en-us/vbcn7/html/vbconScope.asp

Hope this helps
Jay

 

[wk6pack]

yes, I was trying to use it in the finally block.

Will