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The ENDCALL allows you to call more complex COM methods. The normal CALL service only allows you to pass values. However, some COM methods behave differently if you omit parameters, or you might need to pass objects as parameters. In those cases, you will use this service, along with BEGINCALL and ADDPARAM, to call such methods. This is always the final step in the process. First you must use the BEGINCALL service followed by one or more calls to ADDPARAM.

Example

Here is a real world use case. In the Excel object model, there is a ListObjects class. You can add a variety of Excel objects to this class, and if you add a Range to it, there is a parameter that you must omit or the method will fail. This means we need that ability to pass an object and omit a parameter. The CALL service can't do this for us, so we'll use BEGINCALL...ENDCALL instead.

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