> I'm having a type mismatch problem when trying to pass a typed dataset
> to a web service.
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>
> It is obviously treating the two data types as being different.
It's because they are two different data types as far as .NET knows. Even though the MainData you have generated on the client is logically the same because it was generated from the same XSD, it's not the same .NET type. So you have to use the MainData class generated by the web reference.
> If I change the parameter type of the PassData function to type
> DataSet then the function can be called OK, but then I lose the type
> information.
Yeah, you shouldn't have to go this route though. It's less type specific and what you're doing is a perfectly viable solution. I think you're just getting confused by .NET typing vs. XSD typing.
HTH,
Drew