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Com visible types should be creatable







Breaking Change


A reference type that is specifically marked as visible to COM contains a public parameterized constructor but does not contain a public default (parameterless) constructor.

A type without a public default constructor is not creatable by COM clients. However, the type is still accessible to COM clients if another means is available to create the type and pass it to the client, for example, through the return value of a method call.

The rule ignores types derived from System.Delegate.

By default, the following are visible to COM: assemblies, public types, public instance members in public types, and all members of public value types.

To fix a violation of this rule, add a public default constructor or remove the System.Runtime.InteropServices.ComVisibleAttribute from the type.

It is safe to exclude a warning from this rule if other ways are provided to create and pass the object to the COM client.