socket-object-reference
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.