A Custom Action is a collection of compiled C# code which can be used to run methods inside classes with predefined interfaces. An interface is an agreement which determines a minimum set of methods a class should implement. Using Custom Actions, you can define actions that can push or pull data to/from external applications or databases, build and run a complex calculation logic, create custom data validation, and other similar operations that can be executed during application runtime. This involves uploading a compatible .NET assembly with custom code that will be executed during the regular execution of calculations, based on implemented methods.
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