TcpConnection

Struct · namespace System.Net · Since 0.30

struct TcpConnection : IDisposable

A TCP connection: bytes in both directions, to a server (TcpConnection.Connect) or from a client (TcpListener.Accept).

using var connection = try TcpConnection.Connect("example.com", 80);
try connection.WriteText("GET / HTTP/1.1\r\nHost: example.com\r\nConnection: close\r\n\r\n");
var buffer = new uint8[4096];
while (true)
{
    int got = try connection.Read(buffer, 0, buffer.Length);
    if (got == 0)
        break; // the server closed the connection
    Console.Write(try Encoding.UTF8().GetString(buffer, 0, got));
}

Copies of a connection share it, and TcpConnection.Close of one closes it for all of them; keep one owner. The zero value (TcpConnection { }) is a closed connection. Only IPv4.

Static methods

Name	Description
Connect	Connects to port of host: a name ("example.com", "localhost") or an IPv4 address ("192.168.1.10").

Connect

static NetError<TcpConnection> Connect(StringSlice host, int port)

Connects to port of host: a name ("example.com", "localhost") or an IPv4 address ("192.168.1.10").

Errors

• NetError.CannotResolve: the name is unknown (or there is no network).
• NetError.CannotConnect: nothing listens on the port, or the host cannot be reached.
• NetError.NotSupported: WebAssembly and AmigaOS.

Panics when port is not in 0..65535.

Methods

Name	Description
IsOpen	Whether the connection is open (not closed yet by TcpConnection.Close).
WaitForData	Waits up to milliseconds until TcpConnection.Read can return without waiting: data arrived, or the other side closed the connection (0: does not wait; -1: waits as long as it takes).
Read	Reads what has arrived, up to count bytes, into buffer[offset..]; waits until something arrives.
Write	Sends all of bytes: an array, a part of one, or the bytes of a text (text.AsBytes()).
WriteText	Sends text as UTF-8 bytes.
Close	Closes the connection; the copies of it are closed as well.
Dispose	Closes the connection (TcpConnection.Close); using calls it.

IsOpen

bool IsOpen()

Whether the connection is open (not closed yet by TcpConnection.Close). That the other side closed it shows when TcpConnection.Read returns 0.

WaitForData

bool WaitForData(int milliseconds)

Waits up to milliseconds until TcpConnection.Read can return without waiting: data arrived, or the other side closed the connection (0: does not wait; -1: waits as long as it takes).

Returns whether TcpConnection.Read would return at once; false when the time is up (or the connection is closed).

Read

NetError<int> Read(uint8[] buffer, int offset, int count)

Reads what has arrived, up to count bytes, into buffer[offset..]; waits until something arrives.

Returns the number of bytes; 0 when the other side closed the connection and everything was read.

Errors

• NetError.ConnectionLost: the connection is closed, or the other side reset it.

Panics when offset..offset + count is not inside of buffer.

Write

NetError<void> Write(ReadOnlySlice<uint8> bytes)

Sends all of bytes: an array, a part of one, or the bytes of a text (text.AsBytes()).

Errors

• NetError.ConnectionLost: the connection is closed, or the other side closed or reset it.

WriteText

NetError<void> WriteText(StringSlice text)

Sends text as UTF-8 bytes.

Errors

• NetError.ConnectionLost: the connection is closed, or the other side closed or reset it.

Close

void Close()

Closes the connection; the copies of it are closed as well. Closing it again does nothing.

Dispose

void Dispose()

Closes the connection (TcpConnection.Close); using calls it.