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Socket Object Reference

This section provides details of the object's properties and methods.

Socket object constructor:

[new] Socket();

Creates and returns a new Socket object.


Attributes

Socket.connected

socketObj.connected

Description

When true, the connection is active.

Type

Boolean. Read only.


Socket.encoding

socketObj.encoding

Description

Sets or retrieves the name of the encoding used to transmit data.

Typical values are "ASCII", "BINARY", or "UTF-8".

Type

String


Socket.eof

socketObj.eof

Description

When true, the receive buffer is empty.

Type

Boolean. Read only.


Socket.error

socketObj.error

Description

A message describing the most recent error. Setting this value clears any error message.

Type

String


Socket.host

socketObj.host

Description

The name of the remote computer when a connection is established.

If the connection is shut down or does not exist, the property contains the empty string.

Type

String. Read only.


Socket.timeout

socketObj.timeout

Description

The timeout in seconds to be applied to read or write operations. Default is 10.

Type

Number


Methods

Socket.close()

socketObj.close();

Description

Terminates the open connection. Deleting the object also closes the connection, but not until JavaScript garbage-collects the object.

The connection might stay open longer than you wish if you do not close it explicitly.

Returns

Boolean. true if the connection was closed, false on I/O errors.


Socket.listen()

socketObj.listen(port[, encoding="ASCII"]);

Description

Instructs the object to start listening for an incoming connection.

The call to open() and the call to listen() are mutually exclusive. Call one function or the other, not both.

Parameters

Parameter Type Description
port Number. The TCP/IP port number to listen on. Valid port numbers are [1..65535]. Typical values are 80 for a Web server, 23 for a Telnet server and so on.
encoding String Optional. The encoding to be used for the connection. Typical values are "ASCII", "binary", or "UTF-8". Default is "ASCII"

Returns

Boolean. true on success.


Socket.open()

socketObj.open(host[, encoding="ASCII"]);

Description

Opens the connection for subsequent read/write operations.

The call to open() and the call to listen() are mutually exclusive. Call one function or the other, not both.

Parameters

Parameter Type Description
host String The name or IP address of the remote computer, followed by a colon and the port number to connect to. The port number is required. Valid computer names are, for example, "www.adobe.com:80" or "192.150.14.12:80".
encoding String Optional. The encoding to be used for the connection. Typical values are "ASCII", "binary", or "UTF-8". Default is "ASCII"

Returns

Boolean. true on success.


Socket.poll()

socketObj.poll();

Description

Checks a listening object for a new incoming connection. If a connection request was detected, the method returns a new Socket object that wraps the new connection. Use this connection object to communicate with the remote computer.

After use, close the connection and delete the JavaScript object. If no new connection request was detected, the method returns null.

Parameters

Returns

Socket object or null.


Socket.read()

socketObj.read([count=0]);

Description

Reads up to the specified number of characters from the connection, waiting if necessary.

Ignores CR characters unless encoding is set to BINARY.

Parameters

Parameter Type Description
count Number Optional. The number of characters to read. If negative, the call is equivalent to readln(). Default is 0.

Returns

String that contains up to the number of characters that were supposed to be read, or the number of characters read before the connection closed or timed out.


Socket.readln()

socketObj.readln();

Description

Parameters

Reads one line of text up to the next line feed. Line feeds are recognized as LF or CRLF pairs.

CR characters are ignored.

Returns

String


Socket.write()

socketObj.write(text[, text...]);

Description

Concatenates all arguments into a single string and writes that string to the connection.

CRLF sequences are converted to LFs unless encoding is set to BINARY.

Parameters

Parameter Type Description
text String. Any number of string values. All arguments are concatenated to form the string to be written.

Returns

Boolean. true on success.


Socket.writeln()

socketObj.writeln(text[, text...]);

Description

Concatenates all arguments into a single string, appends a Line Feed character, and writes that string to the connection.

Parameters

Parameter Type Description
text String. Any number of string values. All arguments are concatenated to form the string to be written.

Returns

Boolean. true on success.