AsyncStateMachineAttribute Identities the async state machine type for this method.

 CallerFilePathAttribute Allows you to obtain the full path of the source file that contains the caller. This is the file path at the time of compile.

 CallerLineNumberAttribute Allows you to obtain the line number in the source file at which the method is called.

 CallerMemberNameAttribute Allows you to obtain the method or property name of the caller to the method.

 IteratorStateMachineAttribute Identities the iterator state machine type for this method.

 StateMachineAttribute Identities the state machine type for this method.