[Mono-list] Using Exceptions with external Plugins

[Arild Fines]

mono-list-admin@lists.ximian.com wrote:
> Cool! Thanks!
>
> Now, how can I get sure that the InnerException is a
> XmlRpcFaultException or a XmlRpcMissedSomething?, I'm trying with this:
>
> } catch(TargetInvocationException e) {
>    if(e.InnerException.GetType().ToString() ==
> "CookComputing.XmlRpc.XmlRpcFaultException") {
>    Console.WriteLine("yes");
> }
>
> But I don't think it's the correct way/code, any suggestions?

You might want to take advantage of the fact that Type.InvokeMember actually
performs virtual dispatch based on the runtime type of the object *AND* all
of the parameters, IE, it performs double/triple/ntuple dispatch.

That means the following will work the way you want it to:

catch( TargetInvocationException e )
{
	Type t = this.GetType();
	t.InvokeMember( "HandleException", BindingFlags.InvokeMethod |
		BindingFlags.Instance | BindingFlags.NonPublic, null,
            this, new object[]{ e } );
}

// ...

private void HandleException( CookComputing.XmlRpc.XmlRpcFaultException e )
{
   //...
}

private void HandleException( FooException e )
{
   //...
}

private void HandleException( Exception e )
{
   // called if there are no other matching signatures
}

Of course, it isn't particularly fast...

--
Arild

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