You learn something new everyday…

Ok, I know that Paul knew this, but did anyone else notice that the VB.NET Try…Catch syntax includes a ‘when’ clause?

       [ tryStatements ]
    [ Catch [ exception [ As type ] ] [ When expression ] 
       [ catchStatements ] ]
    [ Exit Try ]
    [ Finally
       [ finallyStatements ] ]
    End Try


    Optional. A Catch statement with a When clause will only catch exceptions when expression evaluates to True. A When clause is only applied after checking the type of the exception, and expression may refer to the identifier representing the exception.

I never did! I can’t think of a good use for it right at this moment, but I’m still shocked that I never noticed it before… now what to do with it?

Author: Duncan Mackenzie

I'm the Developer Lead for the Channel 9 team, formerly worked on MSDN as a developer, content strategist and author.

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