Interfaces can be marshaled by value. For an interface marshaled by value (as opposed to a class instance derived from that interface), only the type ID of the most-derived interface is encoded.

We use the following Slice definitions in our discussion:

interface Base { /* ... */ }

interface Derived extends Base { /* ... */ }

interface Example
{
    void doSomething(Base b);
}

We assume that the client passes a class instance to doSomething that does not have a Slice definition (but implements Derived).

Interface Encoding version 1.0

The on-the-wire representation of the interface parameter using encoding version 1.0 is as follows:

Interface Encoding version 1.1

With encoding version 1.1, the interface parameter is encoded as if it was a class with no data members. Here is the on-the-wire representation using the sliced format:

The compact format omits the byte count for the slice:

See Also

• Passing Interfaces by Value
• Type IDs
• Data Encoding for Classes