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class in UnityEngine.Networking

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A High level network connection. This is used for connections from client-to-server and for connection from server-to-client.

A NetworkConnection corresponds to a specific connection for a host in the transport layer. It has a connectionId that is assigned by the transport layer and passed to the Initialize function.

A NetworkClient has one NetworkConnection. A NetworkServerSimple manages multiple NetworkConnections. The NetworkServer has multiple "remote" connections and a "local" connection for the local client.

The NetworkConnection class provides message sending and handling facilities. For sending data over a network, there are methods to send message objects, byte arrays, and NetworkWriter objects. To handle data arriving from the network, handler functions can be registered for message Ids, byte arrays can be processed by HandleBytes(), and NetworkReader object can be processed by HandleReader().

NetworkConnection objects also act as observers for networked objects. When a connection is an observer of a networked object with a NetworkIdentity, then the object will be visible to corresponding client for the connection, and incremental state changes will be sent to the client.

NetworkConnection objects can "own" networked game objects. Owned objects will be destroyed on the server by default when the connection is destroyed. A connection owns the player objects created by its client, and other objects with client-authority assigned to the corresponding client.

There are many virtual functions on NetworkConnection that allow its behaviour to be customized. NetworkClient and NetworkServer can both be made to instantiate custom classes derived from NetworkConnection by setting their networkConnectionClass member variable.


addressThe IP address associated with the connection.
clientOwnedObjectsA list of the NetworkIdentity objects owned by this connection.
connectionIdUnique identifier for this connection that is assigned by the transport layer.
hostIdTransport level host ID for this connection.
isConnectedTrue if the connection is connected to a remote end-point.
isReadyFlag that tells if the connection has been marked as "ready" by a client calling ClientScene.Ready().
lastErrorThe last error associated with this connection.
lastMessageTimeThe last time that a message was received on this connection.
logNetworkMessagesSetting this to true will log the contents of network message to the console.
playerControllersThe list of players for this connection.

Public Methods

CheckHandlerThis function checks if there is a message handler registered for the message ID.
DisconnectDisconnects this connection.
DisposeDisposes of this connection, releasing channel buffers that it holds.
FlushChannelsThis causes the channels of the network connection to flush their data to the transport layer.
GetStatsInGet statistics for incoming traffic.
GetStatsOutGet statistics for outgoing traffic.
InitializeThis inializes the internal data structures of a NetworkConnection object, including channel buffers.
InvokeHandlerThis function invokes the registered handler function for a message.
InvokeHandlerNoDataThis function invokes the registered handler function for a message, without any message data.
RegisterHandlerThis registers a handler function for a message Id.
ResetStatsResets the statistics that are returned from NetworkClient.GetConnectionStats().
SendThis sends a network message with a message ID on the connection. This message is sent on channel zero, which by default is the reliable channel.
SendByChannelThis sends a network message on the connection using a specific transport layer channel.
SendBytesThis sends an array of bytes on the connection.
SendUnreliableThis sends a network message with a message ID on the connection. This message is sent on channel one, which by default is the unreliable channel.
SendWriterThis sends the contents of a NetworkWriter object on the connection.
SetChannelOptionThis sets an option on the network channel.
SetMaxDelayThe maximum time in seconds that messages are buffered before being sent.
ToStringReturns a string representation of the NetworkConnection object state.
TransportReceiveThis virtual function allows custom network connection classes to process data from the network before it is passed to the application.
TransportSendThis virtual function allows custom network connection classes to process data send by the application before it goes to the network transport layer.
UnregisterHandlerThis removes the handler registered for a message Id.

Protected Methods

HandleBytesThis makes the connection process the data contained in the buffer, and call handler functions.
HandleReaderThis makes the connection process the data contained in the stream, and call handler functions.

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