I have to read and write data through a protocol where the response XML maybe different according to the error state of the server application. If the response is good it uses let's say Xml_1 with a specific schema but if the response indicates an error it uses Xml_2 with a complete different schema. The good design , in my opinion would be to incorporate the error state to the first schema, but we are just consumers of the this service and we don't have access to the design of the server application. My solution is to (using C#) read the XML response as string, do some searching in order to understand which XML schema is in use and then using the appropriate XML Serializer to convert the response to an object. Is there a more elegant solution?

CodePudding user response：

Is the union of the two schemas a valid schema? (This will typically be the case, for example, if they use different namespaces, but it's likely not to be the case if they are both no-namespace schemas or if they are two versions of the same schema).

If the union is a valid schema, then you could consider validing against that.

Otherwise peeking at the start of the file will often be enough to tell you which vocabulary is in use.

It's possible to parse an XML document without validation, inspect it, and then validate the already parsed document. It's even possible to do this in a single pipeline without putting the whole document in memory. But the details depend on the toolkit you are using. You've tagged the question C# - I'm not sure if this is possible using the Microsoft tools, but it should be possible I think using Saxon-CS. [Disclaimer, my product].