Updating a client when the service changes
When a service changes, a client built against the old version may stop compiling. The fix is to refresh the reference so the client sees the new contract.
What a reference is
When you add a service reference, the editor generates a proxy class from the service description. The client code talks to that proxy, not to the service directly.
After the service changes
- Update the reference so the proxy is regenerated from the new description.
- Read the changes carefully. A renamed method or a changed return type will need code changes on the client.
- Build and test both sides together, because they now share a contract.
Additive changes are gentler. Adding a new method rarely breaks a client. Removing or renaming one usually does. Treat the contract as a promise and change it carefully.
That completes the web services track. The data behind every service comes from a database, so the next track, installing and running SQL Server, covers the engine itself.