13.8. Use Optional Parameters
Problem
You need to call a method in a COM component without supplying all the required parameters.
Solution
Use the Type.Missing field.
How It Works
The .NET Framework is designed with a heavy use of method overloading. Most methods are overloaded several times so that you can call the version that requires only the parameters you choose to supply. COM, on the other hand, does not support method overloading. Instead, COM components usually use methods with a long list of optional parameters. You do not need to specify values for the optional parameters. For example, if a method includes three optional parameters, you can assign a value to the first and third one, skipping the second one. Passing Nothing to the ...
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