Last week, I got an e-mail from a customer using our web services. They were wondering some operations were not working properly when no input parameters were given. This raised an eyebrow at first, as my documentation clearly stated that this information was mandatory.
It would soon become clear, that the developer in question did not read said documentation at all, but was in fact flying blind on the WSDL. Indeed, the input message schema said everything was optional; this is default behavior for WCF. In this article, I'll work on fixing this minor caveat in the interest of interoperability.
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