For the following Protocol Buffer message (proto3) how to I determine which type is set? There does not seem to be a "has_reply" method as is the case for the generated C++ version.
message Event {
oneof type {
Connection connection = 1;
StatusReply reply = 2;
Error error = 3;
End end = 4;
Empty empty = 5;
};
}
https://developers.google.com/protocol-buffers/docs/reference/csharp-generated#oneof suggests that TypeOneofCase
will tell you which is set:
Oneof Fields
Each field within a oneof has a separate property, like a regular singular field. However, the compiler also generates an additional property to determine which field in the enum has been set, along with an enum and a method to clear the oneof. For example, for this oneof field definition
oneof avatar { string image_url = 1; bytes image_data = 2; }
The compiler will generate these public members:
enum AvatarOneofCase { None = 0, ImageUrl = 1, ImageData = 2 } public AvatarOneofCase AvatarCase { get; } public void ClearAvatar(); public string ImageUrl { get; set; } public ByteString ImageData { get; set; }
If a property is the current oneof "case", fetching that property will return the value set for that property. Otherwise, fetching the property will return the default value for the property's type - only one member of a oneof can be set at a time.
Setting any constituent property of the oneof will change the reported "case" of the oneof. As with a regular singular field, you cannot set a oneof field with a string or bytes type to a null value. Setting a message-type field to null is equivalent to calling the oneof-specific Clear method.