HTML 5学習のWebSocket通信(六)
119138 ワード
WebSocketは次世代クライアントサーバの非同期通信方法である.
WebSocketの最も偉大な点は、サーバとクライアントがいつでも情報をプッシュできることです.
WebSocketはドメイン間通信を許可
Ajaxテクノロジーでは、WebSocketサーバとクライアントが互いに情報をプッシュできるようにクライアントから要求を開始する必要があります.
簡単なリアルタイムマルチチャットシステムを実現します
WebSocketサービス:
WebSocketクライアント:
WebSocketの限界
WebSocketの利点は多く挙げられていますが、進化中のWeb仕様として、Websocketでアプリケーションを構築するリスクも見られます.まず、WebSocket仕様はまだ草案の段階にあります.つまり、その仕様とAPIは変動する可能性があります.もう一つのリスクは、マイクロソフトのIEが市場シェアが最も大きいブラウザとして、他の主流ブラウザに比べてHTML 5のサポートが悪いことです.これは、エンタープライズクラスのWebアプリケーションを構築する際に考慮しなければならない問題です.
詳細住所:http://www.ibm.com/developerworks/cn/web/1112_huangxa_websocket/
WebSocketの最も偉大な点は、サーバとクライアントがいつでも情報をプッシュできることです.
WebSocketはドメイン間通信を許可
Ajaxテクノロジーでは、WebSocketサーバとクライアントが互いに情報をプッシュできるようにクライアントから要求を開始する必要があります.
簡単なリアルタイムマルチチャットシステムを実現します
WebSocketサービス:
using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Sockets;
using System.Security.Cryptography;
using System.Text;
using System.Threading.Tasks;
namespace WebSocketServer
{
class Program
{
static void Main(string[] args)
{
WebSocketServerTest WSServerTest = new WebSocketServerTest();
WSServerTest.Start();
}
}
public class WebSocketServerTest : IDisposable
{
private WebSocketServer WSServer;
public WebSocketServerTest()
{
//
WSServer = new WebSocketServer();
}
public void Dispose()
{
Close();
}
private void Close()
{
WSServer.Dispose();
GC.SuppressFinalize(this);
}
~WebSocketServerTest()
{
Close();
}
public void Start()
{
WSServer.NewConnection += new NewConnectionEventHandler(WSServer_NewConnection);
WSServer.Disconnected += new DisconnectedEventHandler(WSServer_Disconnected);
WSServer.StartServer();
}
void WSServer_Disconnected(Object sender, EventArgs e)
{
}
void WSServer_NewConnection(string loginName, EventArgs e)
{
}
}
public class Logger
{
public bool LogEvents { get; set; }
public Logger()
{
LogEvents = true;
}
public void Log(string Text)
{
if (LogEvents) Console.WriteLine(Text);
}
}
public enum ServerStatusLevel { Off, WaitingConnection, ConnectionEstablished };
public delegate void NewConnectionEventHandler(string loginName, EventArgs e);
public delegate void DataReceivedEventHandler(Object sender, string message, EventArgs e);
public delegate void DisconnectedEventHandler(Object sender, EventArgs e);
public delegate void BroadcastEventHandler(string message, EventArgs e);
public class WebSocketServer : IDisposable
{
private bool AlreadyDisposed;
private Socket Listener;
private int ConnectionsQueueLength;
private int MaxBufferSize;
private string Handshake;
private StreamReader ConnectionReader;
private StreamWriter ConnectionWriter;
private Logger logger;
private byte[] FirstByte;
private byte[] LastByte;
private byte[] ServerKey1;
private byte[] ServerKey2;
List<SocketConnection> connectionSocketList = new List<SocketConnection>();
public ServerStatusLevel Status { get; private set; }
public int ServerPort { get; set; }
public string ServerLocation { get; set; }
public string ConnectionOrigin { get; set; }
public bool LogEvents
{
get { return logger.LogEvents; }
set { logger.LogEvents = value; }
}
public event NewConnectionEventHandler NewConnection;
public event DataReceivedEventHandler DataReceived;
public event DisconnectedEventHandler Disconnected;
private void Initialize()
{
AlreadyDisposed = false;
logger = new Logger();
Status = ServerStatusLevel.Off;
ConnectionsQueueLength = 500;
MaxBufferSize = 1024 * 100;
FirstByte = new byte[MaxBufferSize];
LastByte = new byte[MaxBufferSize];
FirstByte[0] = 0x00;
LastByte[0] = 0xFF;
logger.LogEvents = true;
}
public WebSocketServer()
{
ServerPort = 4141;
ServerLocation = string.Format("ws://{0}:4141/chat", getLocalmachineIPAddress());
Initialize();
}
public WebSocketServer(int serverPort, string serverLocation, string connectionOrigin)
{
ServerPort = serverPort;
ConnectionOrigin = connectionOrigin;
ServerLocation = serverLocation;
Initialize();
}
~WebSocketServer()
{
Close();
}
public void Dispose()
{
Close();
}
private void Close()
{
if (!AlreadyDisposed)
{
AlreadyDisposed = true;
if (Listener != null) Listener.Close();
foreach (SocketConnection item in connectionSocketList)
{
item.ConnectionSocket.Close();
}
connectionSocketList.Clear();
GC.SuppressFinalize(this);
}
}
public static IPAddress getLocalmachineIPAddress()
{
string strHostName = Dns.GetHostName();
IPHostEntry ipEntry = Dns.GetHostEntry(strHostName);
foreach (IPAddress ip in ipEntry.AddressList)
{
//IPV4
if (ip.AddressFamily == AddressFamily.InterNetwork)
return ip;
}
return ipEntry.AddressList[0];
}
public void StartServer()
{
Char char1 = Convert.ToChar(65533);
Listener = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.IP);
Listener.Bind(new IPEndPoint(getLocalmachineIPAddress(), ServerPort));
Listener.Listen(ConnectionsQueueLength);
logger.Log(string.Format(" 。 ：{0}, ：{1}", getLocalmachineIPAddress(), ServerPort));
logger.Log(string.Format("WebSocket : ws://{0}:{1}/chat", getLocalmachineIPAddress(), ServerPort));
while (true)
{
Socket sc = Listener.Accept();
if (sc != null)
{
System.Threading.Thread.Sleep(100);
SocketConnection socketConn = new SocketConnection();
socketConn.ConnectionSocket = sc;
socketConn.NewConnection += new NewConnectionEventHandler(socketConn_NewConnection);
socketConn.DataReceived += new DataReceivedEventHandler(socketConn_BroadcastMessage);
socketConn.Disconnected += new DisconnectedEventHandler(socketConn_Disconnected);
socketConn.ConnectionSocket.BeginReceive(socketConn.receivedDataBuffer,
0, socketConn.receivedDataBuffer.Length,
0, new AsyncCallback(socketConn.ManageHandshake),
socketConn.ConnectionSocket.Available);
connectionSocketList.Add(socketConn);
}
}
}
void socketConn_Disconnected(Object sender, EventArgs e)
{
SocketConnection sConn = sender as SocketConnection;
if (sConn != null)
{
Send(string.Format("【{0}】 ！", sConn.Name));
sConn.ConnectionSocket.Close();
connectionSocketList.Remove(sConn);
}
}
void socketConn_BroadcastMessage(Object sender, string message, EventArgs e)
{
if (message.IndexOf("login:") != -1)
{
SocketConnection sConn = sender as SocketConnection;
sConn.Name = message.Substring(message.IndexOf("login:") + "login:".Length);
message = string.Format(" 【{0}】 ！", message.Substring(message.IndexOf("login:") + "login:".Length));
}
Send(message);
}
void socketConn_NewConnection(string name, EventArgs e)
{
if (NewConnection != null)
NewConnection(name, EventArgs.Empty);
}
public void Send(string message)
{
foreach (SocketConnection item in connectionSocketList)
{
if (!item.ConnectionSocket.Connected) return;
try
{
if (item.IsDataMasked)
{
DataFrame dr = new DataFrame(message);
item.ConnectionSocket.Send(dr.GetBytes());
}
else
{
item.ConnectionSocket.Send(FirstByte);
item.ConnectionSocket.Send(Encoding.UTF8.GetBytes(message));
item.ConnectionSocket.Send(LastByte);
}
}
catch (Exception ex)
{
logger.Log(ex.Message);
}
}
}
}
public class SocketConnection
{
private Logger logger;
private string name;
public string Name
{
get { return name; }
set { name = value; }
}
private Boolean isDataMasked;
public Boolean IsDataMasked
{
get { return isDataMasked; }
set { isDataMasked = value; }
}
public Socket ConnectionSocket;
private int MaxBufferSize;
private string Handshake;
private string New_Handshake;
public byte[] receivedDataBuffer;
private byte[] FirstByte;
private byte[] LastByte;
private byte[] ServerKey1;
private byte[] ServerKey2;
public event NewConnectionEventHandler NewConnection;
public event DataReceivedEventHandler DataReceived;
public event DisconnectedEventHandler Disconnected;
public SocketConnection()
{
logger = new Logger();
MaxBufferSize = 1024 * 100;
receivedDataBuffer = new byte[MaxBufferSize];
FirstByte = new byte[MaxBufferSize];
LastByte = new byte[MaxBufferSize];
FirstByte[0] = 0x00;
LastByte[0] = 0xFF;
Handshake = "HTTP/1.1 101 Web Socket Protocol Handshake" + Environment.NewLine;
Handshake += "Upgrade: WebSocket" + Environment.NewLine;
Handshake += "Connection: Upgrade" + Environment.NewLine;
Handshake += "Sec-WebSocket-Origin: " + "{0}" + Environment.NewLine;
Handshake += string.Format("Sec-WebSocket-Location: " + "ws://{0}:4141/chat" + Environment.NewLine, WebSocketServer.getLocalmachineIPAddress());
Handshake += Environment.NewLine;
New_Handshake = "HTTP/1.1 101 Switching Protocols" + Environment.NewLine;
New_Handshake += "Upgrade: WebSocket" + Environment.NewLine;
New_Handshake += "Connection: Upgrade" + Environment.NewLine;
New_Handshake += "Sec-WebSocket-Accept: {0}" + Environment.NewLine;
New_Handshake += Environment.NewLine;
}
private void Read(IAsyncResult status)
{
if (!ConnectionSocket.Connected) return;
string messageReceived = string.Empty;
DataFrame dr = new DataFrame(receivedDataBuffer);
try
{
if (!this.isDataMasked)
{
// Web Socket protocol: messages are sent with 0x00 and 0xFF as padding bytes
System.Text.UTF8Encoding decoder = new System.Text.UTF8Encoding();
int startIndex = 0;
int endIndex = 0;
// Search for the start byte
while (receivedDataBuffer[startIndex] == FirstByte[0]) startIndex++;
// Search for the end byte
endIndex = startIndex + 1;
while (receivedDataBuffer[endIndex] != LastByte[0] && endIndex != MaxBufferSize - 1) endIndex++;
if (endIndex == MaxBufferSize - 1) endIndex = MaxBufferSize;
// Get the message
messageReceived = decoder.GetString(receivedDataBuffer, startIndex, endIndex - startIndex);
}
else
{
messageReceived = dr.Text;
}
if ((messageReceived.Length == MaxBufferSize && messageReceived[0] == Convert.ToChar(65533)) ||
messageReceived.Length == 0)
{
logger.Log(" [\"" + string.Format("logout:{0}", this.name) + "\"]");
if (Disconnected != null)
Disconnected(this, EventArgs.Empty);
}
else
{
if (DataReceived != null)
{
logger.Log(" [\"" + messageReceived + "\"]");
DataReceived(this, messageReceived, EventArgs.Empty);
}
Array.Clear(receivedDataBuffer, 0, receivedDataBuffer.Length);
ConnectionSocket.BeginReceive(receivedDataBuffer, 0, receivedDataBuffer.Length, 0, new AsyncCallback(Read), null);
}
}
catch (Exception ex)
{
logger.Log(ex.Message);
logger.Log("Socket 。");
if (Disconnected != null)
Disconnected(this, EventArgs.Empty);
}
}
private void BuildServerPartialKey(int keyNum, string clientKey)
{
string partialServerKey = "";
byte[] currentKey;
int spacesNum = 0;
char[] keyChars = clientKey.ToCharArray();
foreach (char currentChar in keyChars)
{
if (char.IsDigit(currentChar)) partialServerKey += currentChar;
if (char.IsWhiteSpace(currentChar)) spacesNum++;
}
try
{
currentKey = BitConverter.GetBytes((int)(Int64.Parse(partialServerKey) / spacesNum));
if (BitConverter.IsLittleEndian) Array.Reverse(currentKey);
if (keyNum == 1) ServerKey1 = currentKey;
else ServerKey2 = currentKey;
}
catch
{
if (ServerKey1 != null) Array.Clear(ServerKey1, 0, ServerKey1.Length);
if (ServerKey2 != null) Array.Clear(ServerKey2, 0, ServerKey2.Length);
}
}
private byte[] BuildServerFullKey(byte[] last8Bytes)
{
byte[] concatenatedKeys = new byte[16];
Array.Copy(ServerKey1, 0, concatenatedKeys, 0, 4);
Array.Copy(ServerKey2, 0, concatenatedKeys, 4, 4);
Array.Copy(last8Bytes, 0, concatenatedKeys, 8, 8);
// MD5 Hash
System.Security.Cryptography.MD5 MD5Service = System.Security.Cryptography.MD5.Create();
return MD5Service.ComputeHash(concatenatedKeys);
}
public void ManageHandshake(IAsyncResult status)
{
string header = "Sec-WebSocket-Version:";
int HandshakeLength = (int)status.AsyncState;
byte[] last8Bytes = new byte[8];
System.Text.UTF8Encoding decoder = new System.Text.UTF8Encoding();
String rawClientHandshake = decoder.GetString(receivedDataBuffer, 0, HandshakeLength);
Array.Copy(receivedDataBuffer, HandshakeLength - 8, last8Bytes, 0, 8);
// Websocket
if (rawClientHandshake.IndexOf(header) != -1)
{
this.isDataMasked = true;
string[] rawClientHandshakeLines = rawClientHandshake.Split(new string[] { Environment.NewLine }, System.StringSplitOptions.RemoveEmptyEntries);
string acceptKey = "";
foreach (string Line in rawClientHandshakeLines)
{
Console.WriteLine(Line);
if (Line.Contains("Sec-WebSocket-Key:"))
{
acceptKey = ComputeWebSocketHandshakeSecurityHash09(Line.Substring(Line.IndexOf(":") + 2));
}
}
New_Handshake = string.Format(New_Handshake, acceptKey);
byte[] newHandshakeText = Encoding.UTF8.GetBytes(New_Handshake);
ConnectionSocket.BeginSend(newHandshakeText, 0, newHandshakeText.Length, 0, HandshakeFinished, null);
return;
}
string ClientHandshake = decoder.GetString(receivedDataBuffer, 0, HandshakeLength - 8);
string[] ClientHandshakeLines = ClientHandshake.Split(new string[] { Environment.NewLine }, System.StringSplitOptions.RemoveEmptyEntries);
logger.Log(" " + ConnectionSocket.LocalEndPoint + "。 ...");
// Welcome the new client
foreach (string Line in ClientHandshakeLines)
{
logger.Log(Line);
if (Line.Contains("Sec-WebSocket-Key1:"))
BuildServerPartialKey(1, Line.Substring(Line.IndexOf(":") + 2));
if (Line.Contains("Sec-WebSocket-Key2:"))
BuildServerPartialKey(2, Line.Substring(Line.IndexOf(":") + 2));
if (Line.Contains("Origin:"))
try
{
Handshake = string.Format(Handshake, Line.Substring(Line.IndexOf(":") + 2));
}
catch
{
Handshake = string.Format(Handshake, "null");
}
}
// Build the response for the client
byte[] HandshakeText = Encoding.UTF8.GetBytes(Handshake);
byte[] serverHandshakeResponse = new byte[HandshakeText.Length + 16];
byte[] serverKey = BuildServerFullKey(last8Bytes);
Array.Copy(HandshakeText, serverHandshakeResponse, HandshakeText.Length);
Array.Copy(serverKey, 0, serverHandshakeResponse, HandshakeText.Length, 16);
logger.Log(" ...");
ConnectionSocket.BeginSend(serverHandshakeResponse, 0, HandshakeText.Length + 16, 0, HandshakeFinished, null);
logger.Log(Handshake);
}
public static String ComputeWebSocketHandshakeSecurityHash09(String secWebSocketKey)
{
const String MagicKEY = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
String secWebSocketAccept = String.Empty;
// 1. Combine the request Sec-WebSocket-Key with magic key.
String ret = secWebSocketKey + MagicKEY;
// 2. Compute the SHA1 hash
SHA1 sha = new SHA1CryptoServiceProvider();
byte[] sha1Hash = sha.ComputeHash(Encoding.UTF8.GetBytes(ret));
// 3. Base64 encode the hash
secWebSocketAccept = Convert.ToBase64String(sha1Hash);
return secWebSocketAccept;
}
private void HandshakeFinished(IAsyncResult status)
{
ConnectionSocket.EndSend(status);
ConnectionSocket.BeginReceive(receivedDataBuffer, 0, receivedDataBuffer.Length, 0, new AsyncCallback(Read), null);
if (NewConnection != null) NewConnection("", EventArgs.Empty);
}
}
public class DataFrame
{
DataFrameHeader _header;
private byte[] _extend = new byte[0];
private byte[] _mask = new byte[0];
private byte[] _content = new byte[0];
public DataFrame(byte[] buffer)
{
//
_header = new DataFrameHeader(buffer);
//
if (_header.Length == 126)
{
_extend = new byte[2];
Buffer.BlockCopy(buffer, 2, _extend, 0, 2);
}
else if (_header.Length == 127)
{
_extend = new byte[8];
Buffer.BlockCopy(buffer, 2, _extend, 0, 8);
}
//
if (_header.HasMask)
{
_mask = new byte[4];
Buffer.BlockCopy(buffer, _extend.Length + 2, _mask, 0, 4);
}
//
if (_extend.Length == 0)
{
_content = new byte[_header.Length];
Buffer.BlockCopy(buffer, _extend.Length + _mask.Length + 2, _content, 0, _content.Length);
}
else if (_extend.Length == 2)
{
int contentLength = (int)_extend[0] * 256 + (int)_extend[1];
_content = new byte[contentLength];
Buffer.BlockCopy(buffer, _extend.Length + _mask.Length + 2, _content, 0, contentLength > 1024 * 100 ? 1024 * 100 : contentLength);
}
else
{
long len = 0;
int n = 1;
for (int i = 7; i >= 0; i--)
{
len += (int)_extend[i] * n;
n *= 256;
}
_content = new byte[len];
Buffer.BlockCopy(buffer, _extend.Length + _mask.Length + 2, _content, 0, _content.Length);
}
if (_header.HasMask) _content = Mask(_content, _mask);
}
public DataFrame(string content)
{
_content = Encoding.UTF8.GetBytes(content);
int length = _content.Length;
if (length < 126)
{
_extend = new byte[0];
_header = new DataFrameHeader(true, false, false, false, 1, false, length);
}
else if (length < 65536)
{
_extend = new byte[2];
_header = new DataFrameHeader(true, false, false, false, 1, false, 126);
_extend[0] = (byte)(length / 256);
_extend[1] = (byte)(length % 256);
}
else
{
_extend = new byte[8];
_header = new DataFrameHeader(true, false, false, false, 1, false, 127);
int left = length;
int unit = 256;
for (int i = 7; i > 1; i--)
{
_extend[i] = (byte)(left % unit);
left = left / unit;
if (left == 0)
break;
}
}
}
public byte[] GetBytes()
{
byte[] buffer = new byte[2 + _extend.Length + _mask.Length + _content.Length];
Buffer.BlockCopy(_header.GetBytes(), 0, buffer, 0, 2);
Buffer.BlockCopy(_extend, 0, buffer, 2, _extend.Length);
Buffer.BlockCopy(_mask, 0, buffer, 2 + _extend.Length, _mask.Length);
Buffer.BlockCopy(_content, 0, buffer, 2 + _extend.Length + _mask.Length, _content.Length);
return buffer;
}
public string Text
{
get
{
if (_header.OpCode != 1)
return string.Empty;
return Encoding.UTF8.GetString(_content);
}
}
private byte[] Mask(byte[] data, byte[] mask)
{
for (var i = 0; i < data.Length; i++)
{
data[i] = (byte)(data[i] ^ mask[i % 4]);
}
return data;
}
}
public class DataFrameHeader
{
private bool _fin;
private bool _rsv1;
private bool _rsv2;
private bool _rsv3;
private sbyte _opcode;
private bool _maskcode;
private sbyte _payloadlength;
public bool FIN { get { return _fin; } }
public bool RSV1 { get { return _rsv1; } }
public bool RSV2 { get { return _rsv2; } }
public bool RSV3 { get { return _rsv3; } }
public sbyte OpCode { get { return _opcode; } }
public bool HasMask { get { return _maskcode; } }
public sbyte Length { get { return _payloadlength; } }
public DataFrameHeader(byte[] buffer)
{
if (buffer.Length < 2)
throw new Exception(" .");
//
_fin = (buffer[0] & 0x80) == 0x80;
_rsv1 = (buffer[0] & 0x40) == 0x40;
_rsv2 = (buffer[0] & 0x20) == 0x20;
_rsv3 = (buffer[0] & 0x10) == 0x10;
_opcode = (sbyte)(buffer[0] & 0x0f);
//
_maskcode = (buffer[1] & 0x80) == 0x80;
_payloadlength = (sbyte)(buffer[1] & 0x7f);
}
//
public DataFrameHeader(bool fin, bool rsv1, bool rsv2, bool rsv3, sbyte opcode, bool hasmask, int length)
{
_fin = fin;
_rsv1 = rsv1;
_rsv2 = rsv2;
_rsv3 = rsv3;
_opcode = opcode;
//
_maskcode = hasmask;
_payloadlength = (sbyte)length;
}
//
public byte[] GetBytes()
{
byte[] buffer = new byte[2] { 0, 0 };
if (_fin) buffer[0] ^= 0x80;
if (_rsv1) buffer[0] ^= 0x40;
if (_rsv2) buffer[0] ^= 0x20;
if (_rsv3) buffer[0] ^= 0x10;
buffer[0] ^= (byte)_opcode;
if (_maskcode) buffer[1] ^= 0x80;
buffer[1] ^= (byte)_payloadlength;
return buffer;
}
}
}WebSocketクライアント:
<html>
<head>
<meta http-equiv="Content-Type" content="text/html;charset=gb2312">
<title>Web sockets test</title>
<style type="text/css">
.container { font-family: "Courier New"; width: 680px; height: 300px; overflow: auto; border: 1px solid black; }
.LockOff { display: none; visibility: hidden; }
.LockOn { display: block; visibility: visible; position: absolute; z-index: 999; top: 0px; left: 0px; width: 1024%; height: 768%; background-color: #ccc; text-align: center; padding-top: 20%; filter: alpha(opacity=75); opacity: 0.75; }
</style>
<script src="jquery-min.js" type="text/javascript"></script>
<script type="text/javascript">
var ws;
var SocketCreated = false;
var isUserloggedout = false;
function lockOn(str) {
var lock = document.getElementById('skm_LockPane');
if (lock)
lock.className = 'LockOn';
lock.innerHTML = str;
}
function lockOff() {
var lock = document.getElementById('skm_LockPane');
lock.className = 'LockOff';
}
function ToggleConnectionClicked() {
if (SocketCreated && (ws.readyState == 0 || ws.readyState == 1)) {
lockOn(" ...");
SocketCreated = false;
isUserloggedout = true;
ws.close();
} else {
lockOn(" ...");
Log(" ...");
try {
if ("WebSocket" in window) {
ws = new WebSocket("ws://" + document.getElementById("Connection").value);
}
else if ("MozWebSocket" in window) {
ws = new MozWebSocket("ws://" + document.getElementById("Connection").value);
}
SocketCreated = true;
isUserloggedout = false;
} catch (ex) {
Log(ex, "ERROR");
return;
}
document.getElementById("ToggleConnection").innerHTML = " ";
ws.onopen = WSonOpen;
ws.onmessage = WSonMessage;
ws.onclose = WSonClose;
ws.onerror = WSonError;
}
};
function WSonOpen() {
lockOff();
Log(" 。", "OK");
$("#SendDataContainer").show();
ws.send("login:" + document.getElementById("txtName").value);
};
function WSonMessage(event) {
Log(event.data);
};
function WSonClose() {
lockOff();
if (isUserloggedout)
Log("【" + document.getElementById("txtName").value + "】 ！");
document.getElementById("ToggleConnection").innerHTML = " ";
$("#SendDataContainer").hide();
};
function WSonError() {
lockOff();
Log(" 。", "ERROR");
};
function SendDataClicked() {
if (document.getElementById("DataToSend").value.trim() != "") {
ws.send(document.getElementById("txtName").value + " :\"" + document.getElementById("DataToSend").value + "\"");
document.getElementById("DataToSend").value = "";
}
};
function Log(Text, MessageType) {
if (MessageType == "OK") Text = "<span style='color: green;'>" + Text + "</span>";
if (MessageType == "ERROR") Text = "<span style='color: red;'>" + Text + "</span>";
document.getElementById("LogContainer").innerHTML = document.getElementById("LogContainer").innerHTML + Text + "<br />";
var LogContainer = document.getElementById("LogContainer");
LogContainer.scrollTop = LogContainer.scrollHeight;
};
$(document).ready(function () {
$("#SendDataContainer").hide();
var WebSocketsExist = true;
try {
var dummy = new WebSocket("ws://localhost:8989/test");
} catch (ex) {
try {
webSocket = new MozWebSocket("ws://localhost:8989/test");
}
catch (ex) {
WebSocketsExist = false;
}
}
if (WebSocketsExist) {
Log(" WebSocket. !", "OK");
document.getElementById("Connection").value = "192.168.1.108:4141/chat";
} else {
Log(" WebSocket。 。", "ERROR");
document.getElementById("ToggleConnection").disabled = true;
}
$("#DataToSend").keypress(function (evt) {
if (evt.keyCode == 13) {
$("#SendData").click();
evt.preventDefault();
}
})
});
</script>
</head>
<body>
<div id="skm_LockPane" class="LockOff"></div>
<form id="form1" runat="server">
<h1>Web Socket </h1>
<br />
<div>
， WebSocket 。
</div>
:
<input type="text" id="Connection" />
：
<input type="text" id="txtName" value=" " />
<button id='ToggleConnection' type="button" onclick='ToggleConnectionClicked();'> </button>
<br />
<br />
<div id='LogContainer' class='container'></div>
<br />
<div id='SendDataContainer'>
<input type="text" id="DataToSend" size="88" />
<button id='SendData' type="button" onclick='SendDataClicked();'> </button>
</div>
<br />
</form>
</body>
</html>WebSocketの限界
WebSocketの利点は多く挙げられていますが、進化中のWeb仕様として、Websocketでアプリケーションを構築するリスクも見られます.まず、WebSocket仕様はまだ草案の段階にあります.つまり、その仕様とAPIは変動する可能性があります.もう一つのリスクは、マイクロソフトのIEが市場シェアが最も大きいブラウザとして、他の主流ブラウザに比べてHTML 5のサポートが悪いことです.これは、エンタープライズクラスのWebアプリケーションを構築する際に考慮しなければならない問題です.
詳細住所:http://www.ibm.com/developerworks/cn/web/1112_huangxa_websocket/