As with PHP, the C# language provides a huge number of libraries--both proprietary and third-party--that provide everything from basic string handling to image manipulation. To connect to the XML-RPC API in Moodle, we will use the XML-RPC library developed by Charles Cook--check out http://cookcomputing.com/blog/index.html for details. The component we need is CookComputing.XmlRpcV2.dll. To install this component, download the relevant DLL, and in the Solution Explorer, right-click on References and select the Add Reference... option:
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Browse to locate the DLL and follow the instructions to import it. A new reference to CookComputing.XmlRpcV2 will be added to the project:
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Go back to the application's Windows form and double-click on the button. This will add a new method to harness.cs to support the button click event. This is where we will need...