TcpClient Class
Provides client connections for TCP network services.
Namespace: System.Net.Sockets
Assembly: System (in System.dll)
The TcpClient type exposes the following members.
| Name | Description | |
|---|---|---|
![]() | TcpClient() | Initializes a new instance of the TcpClient class. |
![]() | TcpClient(AddressFamily) | Initializes a new instance of the TcpClient class with the specified family. |
![]() | TcpClient(IPEndPoint) | Initializes a new instance of the TcpClient class and binds it to the specified local endpoint. |
![]() | TcpClient(String, Int32) | Initializes a new instance of the TcpClient class and connects to the specified port on the specified host. |
| Name | Description | |
|---|---|---|
![]() | Active | Gets or set a value that indicates whether a connection has been made. |
![]() | Available | Gets the amount of data that has been received from the network and is available to be read. |
![]() | Client | Gets or sets the underlying Socket. |
![]() | Connected | Gets a value indicating whether the underlying Socket for a TcpClient is connected to a remote host. |
![]() | ExclusiveAddressUse | Gets or sets a Boolean value that specifies whether the TcpClient allows only one client to use a port. |
![]() | LingerState | Gets or sets information about the linger state of the associated socket. |
![]() | NoDelay | Gets or sets a value that disables a delay when send or receive buffers are not full. |
![]() | ReceiveBufferSize | Gets or sets the size of the receive buffer. |
![]() | ReceiveTimeout | Gets or sets the amount of time a TcpClient will wait to receive data once a read operation is initiated. |
![]() | SendBufferSize | Gets or sets the size of the send buffer. |
![]() | SendTimeout | Gets or sets the amount of time a TcpClient will wait for a send operation to complete successfully. |
| Name | Description | |
|---|---|---|
![]() | BeginConnect(IPAddress, Int32, AsyncCallback, Object) | Begins an asynchronous request for a remote host connection. The remote host is specified by an IPAddress and a port number (Int32). |
![]() | BeginConnect(IPAddress[], Int32, AsyncCallback, Object) | Begins an asynchronous request for a remote host connection. The remote host is specified by an IPAddress array and a port number (Int32). |
![]() | BeginConnect(String, Int32, AsyncCallback, Object) | Begins an asynchronous request for a remote host connection. The remote host is specified by a host name (String) and a port number (Int32). |
![]() | Close | Disposes this TcpClient instance and requests that the underlying TCP connection be closed. |
![]() | Connect(IPEndPoint) | Connects the client to a remote TCP host using the specified remote network endpoint. |
![]() | Connect(IPAddress, Int32) | Connects the client to a remote TCP host using the specified IP address and port number. |
![]() | Connect(IPAddress[], Int32) | Connects the client to a remote TCP host using the specified IP addresses and port number. |
![]() | Connect(String, Int32) | Connects the client to the specified port on the specified host. |
![]() | ConnectAsync(IPAddress, Int32) | Connects the client to a remote TCP host using the specified IP address and port number as an asynchronous operation. |
![]() | ConnectAsync(IPAddress[], Int32) | Connects the client to a remote TCP host using the specified IP addresses and port number as an asynchronous operation. |
![]() | ConnectAsync(String, Int32) | Connects the client to the specified TCP port on the specified host as an asynchronous operation. |
![]() | Dispose | Releases the unmanaged resources used by the TcpClient and optionally releases the managed resources. |
![]() | EndConnect | Ends a pending asynchronous connection attempt. |
![]() | Equals(Object) | Determines whether the specified object is equal to the current object. (Inherited from Object.) |
![]() | Finalize | Frees resources used by the TcpClient class. (Overrides Object.Finalize().) |
![]() | GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
![]() | GetStream | Returns the NetworkStream used to send and receive data. |
![]() | GetType | Gets the Type of the current instance. (Inherited from Object.) |
![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() | ToString | Returns a string that represents the current object. (Inherited from Object.) |
The TcpClient class provides simple methods for connecting, sending, and receiving stream data over a network in synchronous blocking mode.
In order for TcpClient to connect and exchange data, a TcpListener or Socket created with the TCP ProtocolType must be listening for incoming connection requests. You can connect to this listener in one of the following two ways:
Create a TcpClient and call one of the three available Connect methods.
Create a TcpClient using the host name and port number of the remote host. This constructor will automatically attempt a connection.
Note |
|---|
If you want to send connectionless datagrams in synchronous blocking mode, use the UdpClient class. |
To send and receive data, use the GetStream method to obtain a NetworkStream. Call the Write and Read methods of the NetworkStream to send and receive data with the remote host. Use the Close method to release all resources associated with the TcpClient.
The following code example establishes a TcpClient connection.
static void Connect(String server, String message) { try { // Create a TcpClient. // Note, for this client to work you need to have a TcpServer // connected to the same address as specified by the server, port // combination. Int32 port = 13000; TcpClient client = new TcpClient(server, port); // Translate the passed message into ASCII and store it as a Byte array. Byte[] data = System.Text.Encoding.ASCII.GetBytes(message); // Get a client stream for reading and writing. // Stream stream = client.GetStream(); NetworkStream stream = client.GetStream(); // Send the message to the connected TcpServer. stream.Write(data, 0, data.Length); Console.WriteLine("Sent: {0}", message); // Receive the TcpServer.response. // Buffer to store the response bytes. data = new Byte[256]; // String to store the response ASCII representation. String responseData = String.Empty; // Read the first batch of the TcpServer response bytes. Int32 bytes = stream.Read(data, 0, data.Length); responseData = System.Text.Encoding.ASCII.GetString(data, 0, bytes); Console.WriteLine("Received: {0}", responseData); // Close everything. stream.Close(); client.Close(); } catch (ArgumentNullException e) { Console.WriteLine("ArgumentNullException: {0}", e); } catch (SocketException e) { Console.WriteLine("SocketException: {0}", e); } Console.WriteLine("\n Press Enter to continue..."); Console.Read(); }
- SocketPermission
Permission to establish an outgoing connection or accept an incoming request.
Windows 8, Windows Server 2012, Windows 7, Windows Vista SP2, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role supported with SP1 or later; Itanium not supported)
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.






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