f9/sdk/dart/package-fidl_fidl/Encoder/encodeUnknownMethodResponse.md

# encodeUnknownMethodResponse method








void encodeUnknownMethodResponse
(int methodOrdinal, int txid)





<p>Produces a response for an UnknownMethod which was called with the given
ordinal value for the method and the given transaction ID. This produces
both a message header and an encoded body. The header will have the
provided ordinal and txid and CallStrictness.flexible (this should never
be used with a strict method). The body will contain a union with ordinal
3 and a value of type zx_status with the NOT_SUPPORTED error code.</p>



## Implementation

```dart
void encodeUnknownMethodResponse(int methodOrdinal, int txid) {
  encodeMessageHeader(methodOrdinal, txid, CallStrictness.flexible);

  const int kUnknownMethodInlineSize = 16;
  const int kEnvelopeOffset = kMessageHeaderSize + 8;
  const int kTransportErrOrdinal = 3;
  alloc(kUnknownMethodInlineSize, 0);
  // Union header.
  // transport_err value for the union's ordinal.
  encodeUint64(kTransportErrOrdinal, kMessageHeaderSize);
  // Inline value of the zx_status.
  encodeInt32(ZX.ERR_NOT_SUPPORTED, kEnvelopeOffset);
  // Number of handles in the envelope.
  encodeUint16(0, kEnvelopeOffset + 4);
  // Flags field, with tag indicating the value is stored in-line (in what
  // would otherwise be the size field).
  encodeUint16(kEnvelopeInlineMarker, kEnvelopeOffset + 6);
}
```