Returning Floats and Doubles from Automation methods

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Automation methods and properties can be marked as using one of the calling conventions described by the CALLCONV enumeration. This calling convention is used by the standard IDispatch implementation provided by CreateStdDispatch and by DispInvoke to call property accessor functions or methods.

NOTE: An automation controller does not directly use these calling conventions.

Because of a C Language implementation limitation, automation properties and methods that return Float or Double cannot use the C calling convention. You need to use the Pascal calling convention.

For example, describe a method or automation property that returns a Float or Double as follows in the .ODL file:

[propget] float pascal MyProperty(); float pascal MyMethod();