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websocket只连接了一个客户客户端互发消息,但是每发一次消息,服务端就提示连接人数加一个,这是为什么 ``` // concurrent包的线程安全Set,用来存放每个客户端对应的MyWebSocket对象。 服务端 private static CopyOnWriteArraySet<StatusWS> webSocketSet = new CopyOnWriteArraySet<StatusWS>(); private static Map<String, JSONObject> webSocketMap = new HashMap<String, JSONObject>(); // 与某个客户端的连接会话,需要通过它来给客户端发送数据 private Session session; private String APPID; /** * 连接建立成功调用的方法 */ @OnOpen public void onOpen(Session session) { this.session = session; webSocketSet.add(this); // 加入set中 addOnlineCount(); // 在线数加1 logger.info("有新连接加入!当前在线人数为" + getOnlineCount()); } 客户端: $("#btnConnection").click(function() { socket = new WebSocket("ws://203.195.240/status"); //打开事件 socket.onopen = function() { alert("Socket 已打开"); //socket.send("这是来自客户端的消息" + location.href + new Date()); }; //获得消息事件 socket.onmessage = function(msg) { console.log(msg.data); }; //关闭事件 socket.onclose = function() { alert("Socket已关闭"); }; //发生了错误事件 socket.onerror = function() { alert("发生了错误"); } }); //发送消息 $("#btnSend").click(function() { socket.send("1001,1"); }); //关闭 $("#btnClose").click(function() { socket.close(); }); ```

如何使用Go和gorilla websocket仅发送给一个客户端,而不是所有客户端

<div class="post-text" itemprop="text"> <p>I am trying to learn websockets with Go. I have been looking at examples with gorilla websocket.</p> <p>I have checked out these 2 examples that show how to use gorilla websocket:</p> <p><a href="https://github.com/gorilla/websocket/tree/master/examples" rel="nofollow">https://github.com/gorilla/websocket/tree/master/examples</a></p> <p><a href="https://www.youtube.com/watch?v=ysAZ_oqPOo0" rel="nofollow">https://www.youtube.com/watch?v=ysAZ_oqPOo0</a></p> <p>All of these examples show how to connect to a websocket server, send and receive texts. But what I don't understand is how you can send to only one client. Because in a real world application you will have users, and we don't want all users to receive the same message and same data. Is there a way for me to get the unique id of a connection which I can save in a database like redis and link it to a user id in the same database, and then use that websocket id to send back to a specific client if that user id received a message or a notification? Is this how one would go about and achieve something like this? If that is the case, how would I that?</p> </div>

WebSocket 服务端与客户端互发消息问题?

WebSocket 如果服务端不停的发消息给客户端,客户端处理消息又不停的给服务端发处理结果消息,这样会有什么问题?本人遇到的情况是如果服务端一直在发,就收不到客户端发的消息,是不是因为只有一个连接通道,服务端和客户端不能同时发?


<div class="post-text" itemprop="text"> <p><strong>Hi all!</strong></p> <p>I use swoole for WebSockets.</p> <p><strong>I create clietn part:</strong></p> <pre><code>&lt;script&gt; var ws = new WebSocket('ws://site.ll:9502/?user=tester01'); ws.onmessage = function(evt) { console.log(evt.data); }; ws.onopen = function (event) { ws.send('test'); } &lt;/script&gt; </code></pre> <p><strong>Create WebServer part:</strong></p> <pre><code>$server = new swoole_websocket_server("", 9502); $server-&gt;on("start", function ($server) { echo "Swoole http server is started at "; }); $server-&gt;on('open', function($server, $req) { echo "connection open: {$req-&gt;fd} "; }); $server-&gt;on('message', function($server, $frame) { echo "received message: {$frame-&gt;data} "; $server-&gt;push($frame-&gt;fd, json_encode(["hello", "world"])); }); $server-&gt;on('close', function($server, $fd) { echo "connection close: {$fd} "; }); $server-&gt;start(); </code></pre> <p><strong>Create send from server part:</strong></p> <pre><code>$client = new swoole_client(SWOOLE_SOCK_TCP); if (!$client-&gt;connect('', 9502, -1)) { exit("connect failed. Error: {$client-&gt;errCode} "); } $client-&gt;send("hello world "); echo $client-&gt;recv(); $client-&gt;close(); </code></pre> <p>I trying to create TCP server inside WebSocket server, just adding next part inside "on start" callback:</p> <pre><code>$server2 = new swoole_server("", 9503); $server2-&gt;on('connect', function ($server2, $fd){ echo "connection open: {$fd} "; }); $server2-&gt;on('receive', function ($server2, $fd, $from_id, $data) { $server2-&gt;send($fd, "Swoole: {$data}"); $server2-&gt;close($fd); }); $server2-&gt;on('close', function ($server2, $fd) { echo "connection close: {$fd} "; }); $server2-&gt;start(); </code></pre> <p>But Just receive an error: </p> <blockquote> <p>Swoole\Server::__construct(): eventLoop has already been created. unable to create swoole_server.</p> </blockquote> <p>I need to send data from server to client. How can I do this? In workerman library I doing next: <a href="https://github.com/Shkarbatov/WebSocketPHPWorkerman/blob/master/worker.php" rel="nofollow noreferrer">https://github.com/Shkarbatov/WebSocketPHPWorkerman/blob/master/worker.php</a></p> </div>

websocket 用c++编写客户端的问题

用MFC CAsyncSocket这个类的socket与服务器connect之后, 我发送了头:Sec-WebSocket-Key,Sec-WebSocket-Version: 13 等内容 等取得了服务器返回的应答:Sec-WebSocket-Accept,Upgrade:Websocket等内容 应该是握手成功了。 之后我在用CAsyncSocket的send发送文本过去服务器就没有返回数据了,服务器也木有向我返回数据。是不是发送的数据要经过编码或者是什么? 请问有websocket 用c++编写客户端 示例代码吗?


<div class="post-text" itemprop="text"> <p>I'm trying to modify the gorilla chat example to to send a message to a specific client instead of broadcast. First I'm storing the specific client in the hub against it's Id.</p> <p><strong>Hub.go</strong></p> <pre><code>type Hub struct { Clients map[int]*Client // Changed this piece to store id (int) Broadcast chan []byte Register chan *Client Unregister chan *Client } func (h *Hub) Run() { for { select { case client := &lt;-h.Register: fmt.Println("hub client register") h.Clients[client.Id] = client case client := &lt;-h.Unregister: fmt.Println("hub client Unregister") fmt.Println(h.Clients[client.Id]) if h.Clients[client.Id] != nil { delete(h.Clients, client.Id) close(client.Send) } case message := &lt;-h.Broadcast: fmt.Println("to send to a specific client", string(message)) } } } </code></pre> <p><strong>Client</strong></p> <p>I've added a field Id int to Client to know which client has sent a message</p> <pre><code>type Client struct { Hub *Hub Conn *websocket.Conn Send chan []byte Id int // Id of the client, } func (c *Client) readPump() { defer func() { c.Hub.Unregister &lt;- c c.Conn.Close() }() c.Conn.SetReadLimit(maxMessageSize) c.Conn.SetReadDeadline(time.Now().Add(pongWait)) c.Conn.SetPongHandler(func(string) error { c.Conn.SetReadDeadline(time.Now().Add(pongWait)); return nil }) for { _, message, err := c.Conn.ReadMessage() if err != nil { if websocket.IsUnexpectedCloseError(err, websocket.CloseGoingAway) { log.Printf("error: %v", err) } break } message = bytes.TrimSpace(bytes.Replace(message, newline, space, -1)) fmt.Println("client read message", string(message), "from", c.Id) // {"to":512,"message":"Hi there."} c.Hub.Broadcast &lt;- message } } </code></pre> <p>What are the next steps to take to be able to send the message to a specific client instead of broadcasting.</p> <p>the message itself is coming as JSON from the client specifying 'to' indicating who to send and what message to send.</p> <pre><code>{"to":512,"message":"Hi there."} </code></pre> </div>


<div class="post-text" itemprop="text"> <p>I started a personal project from gorilla chat example. Every time a client calls "register" I check if it has an opponent. Suppose clients are game players. What I am trying to do is to couple clients two per two.</p> <p>Clients are:</p> <pre><code>type Client struct { hub *Hub opponent *Client conn *websocket.Conn send chan []byte } </code></pre> <p>So when I client call register, if exists one client with opponent nil, I tie two clients with</p> <pre><code>c.opponent = client client.opponent = c </code></pre> <p>And then, I send together a message:</p> <pre><code>c.conn.WriteMessage(websocket.TextMessage, dat) client.conn.WriteMessage(websocket.TextMessage, dat) </code></pre> <p>but no one receive the message. How can I send a message to just two clients?</p> <pre><code>package main import ( "github.com/gorilla/websocket" "log" ) func newHub() *Hub { return &amp;Hub{ broadcast: make(chan []byte), register: make(chan *Client), unregister: make(chan *Client), clients: make(map[*Client]bool), } } func (h *Hub) run() { for { select { // register new client case client := &lt;-h.register: log.Println("register") h.clients[client] = true for c := range h.clients { if c != client { if c.opponent == nil { c.opponent = client client.opponent = c dat := []byte(`{"foo":"bar"}`) c.conn.WriteMessage(websocket.TextMessage, dat) client.conn.WriteMessage(websocket.TextMessage, dat) } } } case client := &lt;-h.unregister: log.Println("unregister") if _, ok := h.clients[client]; ok { delete(h.clients, client) close(client.send) } case message := &lt;-h.broadcast: for client := range h.clients { select { case client.send &lt;- message: default: close(client.send) delete(h.clients, client) } } } } } </code></pre> </div>


<div class="post-text" itemprop="text"> <p>I am very new to Go and have found myself working with sockets as my first project. This is a redundant question, but I have failed to understand how to send a websocket update to a specific client in Go (using Gorilla).</p> <p>The broad problem that I am trying to solve is - Building a typeahead using websockets and a search engine like ES/Lucene. I have maintained a bunch of indexes on my search engine and have a Go wrapper around it. When I started working on using websockets in Go, I have been finding almost all the examples showing broadcasting mechanism. When I tried to dig into this and tried to modify the example given in Gorilla's github <a href="https://github.com/gorilla/websocket/tree/master/examples/chat" rel="nofollow noreferrer">repo</a> based on the examples given in <a href="https://github.com/gorilla/websocket/issues/46" rel="nofollow noreferrer">this</a> thread and in this <a href="https://stackoverflow.com/questions/31598147/how-to-send-to-only-one-client-and-not-all-clients-using-go-and-gorilla-websocke">answer</a>, I don't seem to understand <code>connections</code> and how does that fit in <code>client.go</code></p> <p>Ideally, the way I would like to see this working is -</p> <ul> <li>A socket connection between the client and server is established</li> <li>Upon the client sending inputs via the socket, the server fetches it and throws into into a channel (Go channel)</li> <li>The indexing wrapper checks for this channel, and once there is something to fetch, the index is retrieved and written back to the socket</li> </ul> <p>How can the server uniquely identify the <code>Client</code>?</p> <p>I have used the examples given on Gorilla's Github <a href="https://github.com/gorilla/websocket/tree/master/examples/chat" rel="nofollow noreferrer">repo</a></p> <p>From my codebase <code>hub.go</code> has the following </p> <pre><code>type Hub struct { // Registered clients. clients map[*Client]bool // Inbound messages from the clients. broadcast chan []byte // Register requests from the clients. register chan *Client // Unregister requests from clients. unregister chan *Client connections map[string]*connection } func newHub() *Hub { return &amp;Hub{ broadcast: make(chan []byte), register: make(chan *Client), unregister: make(chan *Client), clients: make(map[*Client]bool), connection: make(map[*Client]bool), // is this alright? } } func (h *Hub) run() { for { select { case client := &lt;-h.register: h.clients[client] = true case client := &lt;-h.unregister: if _, ok := h.clients[client]; ok { delete(h.clients, client) close(client.send) } case message := &lt;-h.broadcast: for client := range h.connections { select { case client.send &lt;- message: default: close(client.send) delete(h.connections, client) } } } } } </code></pre> <p>and I am unsure with what I should be adding to <code>client.go</code></p> <pre><code>type Client struct { // unique ID for each client // id string // Hub object hub *Hub // The websocket connection. conn *websocket.Conn // Buffered channel of outbound messages. send chan []byte // connection --&gt; (what should the connection property be?) connection string } </code></pre> <p>Please note - I will be adding an <code>Id</code> field within the <code>Client</code> struct. How can I proceed from here?</p> </div>


自己网上找了一个例子,在服务端,我只发送字符串给客户端的时候是正常的,但是当在字符串前面添加int16和int32一起发送回给客户端就报错了:WebSocket connection to 'ws://' failed: One or more reserved bits are on: reserved1 = 1, reserved2 = 0, reserved3 = 1 客户端可以正确读取到前面的两个int数据 但是后面的字符串读取数据不全,而且客户端还报错。求大神帮忙解答下。非常感谢。 https://pan.baidu.com/s/1i7kZy8t 源码地址


<div class="post-text" itemprop="text"> <p>I have a websocket client. In reality, it is far more complex than the basic code shown below. I now need to scale this client code to open connections to multiple servers. Ultimately, the tasks that need to be performed when a message is received from the servers is identical. What would be the best approach to handle this? As I said above the actual code performed when receiving the message is far more complex than shown in the example.</p> <pre><code>package main import ( "flag" "log" "net/url" "os" "os/signal" "time" "github.com/gorilla/websocket" ) var addr = flag.String("addr", "localhost:1234", "http service address") func main() { flag.Parse() log.SetFlags(0) interrupt := make(chan os.Signal, 1) signal.Notify(interrupt, os.Interrupt) // u := url.URL{Scheme: "ws", Host: *addr, Path: "/echo"} u := url.URL{Scheme: "ws", Host: *addr, Path: "/"} log.Printf("connecting to %s", u.String()) c, _, err := websocket.DefaultDialer.Dial(u.String(), nil) if err != nil { log.Fatal("dial:", err) } defer c.Close() done := make(chan struct{}) go func() { defer close(done) for { _, message, err := c.ReadMessage() if err != nil { log.Println("read:", err) return } log.Printf("recv: %s", message) } }() ticker := time.NewTicker(time.Second) defer ticker.Stop() for { select { case &lt;-done: return case t := &lt;-ticker.C: err := c.WriteMessage(websocket.TextMessage, []byte(t.String())) if err != nil { log.Println("write:", err) return } case &lt;-interrupt: log.Println("interrupt") // Cleanly close the connection by sending a close message and then // waiting (with timeout) for the server to close the connection. err := c.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, "")) if err != nil { log.Println("write close:", err) return } select { case &lt;-done: case &lt;-time.After(time.Second): } return } } } </code></pre> </div>

websocket 如果服务端主动断开连接客户端应该如何收到反馈

如果存在服务器主动断开与客户端连接的websocket的情况, 服务器端或者客户端应该如何写才能让客户端接收到连接被断开连接的反馈? 麻烦定时检测是否断开的这种方法就不要说了。

webworker websocket服务端推送消息到客户端?



<div class="post-text" itemprop="text"> <p>I'm trying to create a program that will connect to several servers though gorilla web-sockets. I currently have a program that will iterate over a list of server addresses and create a new goroutine that will create its own Websocket.conn and handle reading and writing. </p> <p>The problem is that every time a new goroutine is created the previous goroutines are blocked and only the last one can continue. I believe this is because the gorilla websocket library is blocking each gorotutine, but I might be mistaken.</p> <p>I have tried putting a timer in the server list iterator and each goroutine will work perfectly but then the moment a new goroutine is made with another address the previous goroutine is blocked.</p> <p>The relevant bits of my code:</p> <p>In my <code>main.go</code></p> <pre class="lang-golang prettyprint-override"><code>for _, server := range servers { go control(ctx, server, port) } </code></pre> <p>In <code>control()</code></p> <pre class="lang-golang prettyprint-override"><code> func control(ctx context.Context, server, port string) { url := url.URL{ Scheme: "ws", Host: server + ":" + port, Path: "", } conn, _, err := websocket.DefaultDialer.Dial(url.String(), nil) if err != nil { panic(err) } defer conn.Close() go sendHandler(ctx, conn) go readHandler(ctx, conn) } readHandler(ctx context.Context, conn *websocket.Con) { for { _, p, err := conn.ReadMessage(); if err != nil { panic(err) } select { case &lt;-ctx.Done(): goto TERM default: // do nothing } } TERM: // do termination } sendHandler(ctx context.Context, conn *websocket.Con) { for _, msg := range msges { err = conn.WriteMessage(websocket.TextMessage, msg) if err != nil { panic(err) } } &lt;-ctx.Done() } </code></pre> <p>I removed the parts where I add waitgroups and other unnecessary pieces of code.</p> <p>So what I expect is for there to be 3n goroutines running (where n is the number of servers) without blocking but right now I see only 3 goroutines running which are the ones called by the last iteration of the server list.</p> <p>Thanks!</p> <p>EDIT 14/06/2019:</p> <p>I spent some time making a small working example and in the example the bug did not occur - none of the threads blocked each other. I'm still unsure what was causing it but here is my small working example:</p> <p><code>main.go</code></p> <pre class="lang-golang prettyprint-override"><code>package main import ( "context" "fmt" "os" "time" "os/signal" "syscall" "sync" "net/url" "github.com/gorilla/websocket" ) func main() { servers := []string{"5555","5556", "5557"} comms := make(chan os.Signal, 1) signal.Notify(comms, os.Interrupt, syscall.SIGTERM) ctx := context.Background() ctx, cancel := context.WithCancel(ctx) var wg sync.WaitGroup for _, server := range servers { wg.Add(1) go control(server, ctx, &amp;wg) } &lt;-comms cancel() wg.Wait() } func control(server string, ctx context.Context, wg *sync.WaitGroup) { fmt.Printf("Started control for %s ", server) url := url.URL { Scheme: "ws", Host: "" + ":" + server, Path: "", } conn, _, err := websocket.DefaultDialer.Dial(url.String(), nil) if err != nil { panic(err) } defer conn.Close() var localwg sync.WaitGroup localwg.Add(1) go sendHandler(ctx, conn, &amp;localwg, server) localwg.Add(1) go readHandler(ctx, conn, &amp;localwg, server) &lt;- ctx.Done() localwg.Wait() wg.Done() return } func sendHandler(ctx context.Context, conn *websocket.Conn, wg *sync.WaitGroup, server string) { for i := 0; i &lt; 50; i++ { err := conn.WriteMessage(websocket.TextMessage, []byte("ping")) if err != nil { panic(err) } fmt.Printf("sent msg to %s ", server) time.Sleep(1 * time.Second) } &lt;- ctx.Done() wg.Done() } func readHandler(ctx context.Context, conn *websocket.Conn, wg *sync.WaitGroup, server string) { for { select { case &lt;- ctx.Done(): wg.Done() return default: _, p, err := conn.ReadMessage() if err != nil { wg.Done() fmt.Println("done") } fmt.Printf("Got [%s] from %s ", string(p), server) } } } </code></pre> <p>I tested it with dpallot's <a href="https://github.com/dpallot/simple-websocket-server" rel="nofollow noreferrer">simple-websocket-server</a> by a server on 5555, 5556 and 5557 respectively.</p> </div>



spring_websocket 客户端不能给服务器发消息

spring_websocket 链接上服务器后调用 send 方法没有向服务器发送请求 ![图片说明](https://img-ask.csdn.net/upload/201609/27/1474968492_820686.png)


<div class="post-text" itemprop="text"> <p>I'm learning WebSocket using PHP library Ratchet. But I have a problem sending the message from client/browser. I have tried using chrome and firefox.</p> <p>The message is not sent to the server until I disconnect the client by closing the tab or refresh the browser.</p> <p>Update: My server use Centos 7 with firewalld enabled.</p> <p>After I close the browser tab, the server output is like this:</p> <pre><code>Connection 73 sending message "tes" to 1 other connection Connection 73 has disconnected </code></pre> <p>Here is the javascript code:</p> <pre><code>conn = new WebSocket('ws://websocket.develop.local:8080'); conn.onopen = function(e) { console.log("Connection established!"); }; conn.onmessage = function(e) { console.log('ada message'); console.log(e.data); }; conn.onerror = function(e) { console.log("WebSocket Error: " , e); //Custom function for handling errors //handleErrors(e); }; function sendMessage(){ var message = document.getElementById("pesan").value; conn.send(message); console.log('Sending message: ' + message); }; </code></pre> <p>And here is the PHP code (I got this from Ratchet docs):</p> <pre><code> &lt;?php namespace MyApp; use Ratchet\MessageComponentInterface; use Ratchet\ConnectionInterface; class Chat implements MessageComponentInterface { protected $clients; public function __construct() { $this-&gt;clients = new \SplObjectStorage; } public function onOpen(ConnectionInterface $conn) { // Store the new connection to send messages to later $this-&gt;clients-&gt;attach($conn); echo "New connection! ({$conn-&gt;resourceId}) "; } public function onMessage(ConnectionInterface $from, $msg) { $numRecv = count($this-&gt;clients) - 1; echo sprintf('Connection %d sending message "%s" to %d other connection%s' . " " , $from-&gt;resourceId, $msg, $numRecv, $numRecv == 1 ? '' : 's'); foreach ($this-&gt;clients as $client) { if ($from !== $client) { // The sender is not the receiver, send to each client connected $client-&gt;send($msg); } } } public function onClose(ConnectionInterface $conn) { // The connection is closed, remove it, as we can no longer send it messages $this-&gt;clients-&gt;detach($conn); echo "Connection {$conn-&gt;resourceId} has disconnected "; } public function onError(ConnectionInterface $conn, \Exception $e) { echo "An error has occurred: {$e-&gt;getMessage()} "; $conn-&gt;close(); } } </code></pre> </div>


<div class="post-text" itemprop="text"> <p>I have a webpage that establishes a websocket connection with the server. I have to make sure that a user of the site can only establish a single connection, so opening a new tab and navigating to the same page will close the previous connection.</p> <p>I was thinking of maintaining a map with the session id as the key; however, as the map would have to be constantly adjusted in size as more and more clients connect I am afraid of it having performance problems, and since it's accessed concurrently you would probably have to do some kind of locking.</p> <p>Any ideas for performance efficient ways of ensuring a unique connection per client? Would love to hear suggestions, thank you.</p> </div>


<div class="post-text" itemprop="text"> <p>Problem is simple: i have WS server that doing it's "for {}". I need "register" connected user, then send message on event(outside of CoreWS function). I'm added NodeJS example that doing exactly what i need, for better understanding.</p> <p>Go Lang Code that fails: i'm using this pkg <a href="https://github.com/gobwas/ws" rel="nofollow noreferrer">https://github.com/gobwas/ws</a></p> <pre><code>var conn_itf interface{} //yeah, var op_itf interface{} //i know it's not how it works func main() { go collector() go sender() http.ListenAndServe(":3333", http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) { conn, _, _, err := ws.UpgradeHTTP(r, w) if err != nil { // handle error } go func() { defer conn.Close() for { msg, op, err := wsutil.ReadClientData(conn) conn_itf = conn // i'm trying to "register" user op_itf = op if err != nil { } err = wsutil.WriteServerMessage(conn, op, msg) if err != nil { } } }() })) } func collector() { for { fmt.Println("conn: ", conn_itf) fmt.Println("op: ", op_itf) time.Sleep(10000 * time.Millisecond) } } func sender() { for { msg := []byte("Hello world!") time.Sleep(50000 * time.Millisecond) wsutil.WriteServerMessage(conn_itf, op_itf, msg) //invoking ws-send } } </code></pre> <p>NodeJS that working:</p> <pre><code>const wss = new WebSocket.Server({ port: 3333 }) wss.on('connection', ws =&gt; { sockets.set('key', ws) //this code remember active connection ws.on('message', message =&gt; { console.log(`Received message =&gt; ${message}`) }) }) function callsend(data) { const ws = sockets.get('key') //this code sending message on invoking ws.send(data) } </code></pre> </div>



MySQL 8.0.19安装教程(windows 64位)

话不多说直接开干 目录 1-先去官网下载点击的MySQL的下载​ 2-配置初始化的my.ini文件的文件 3-初始化MySQL 4-安装MySQL服务 + 启动MySQL 服务 5-连接MySQL + 修改密码 先去官网下载点击的MySQL的下载 下载完成后解压 解压完是这个样子 配置初始化的my.ini文件的文件 ...



Vue.js 2.0之全家桶系列视频课程

基于新的Vue.js 2.3版本, 目前新全的Vue.js教学视频,让你少走弯路,直达技术前沿! 1. 包含Vue.js全家桶(vue.js、vue-router、axios、vuex、vue-cli、webpack、ElementUI等) 2. 采用笔记+代码案例的形式讲解,通俗易懂






【为什么学爬虫?】 &nbsp; &nbsp; &nbsp; &nbsp;1、爬虫入手容易,但是深入较难,如何写出高效率的爬虫,如何写出灵活性高可扩展的爬虫都是一项技术活。另外在爬虫过程中,经常容易遇到被反爬虫,比如字体反爬、IP识别、验证码等,如何层层攻克难点拿到想要的数据,这门课程,你都能学到! &nbsp; &nbsp; &nbsp; &nbsp;2、如果是作为一个其他行业的开发者,比如app开发,web开发,学习爬虫能让你加强对技术的认知,能够开发出更加安全的软件和网站 【课程设计】 一个完整的爬虫程序,无论大小,总体来说可以分成三个步骤,分别是: 网络请求:模拟浏览器的行为从网上抓取数据。 数据解析:将请求下来的数据进行过滤,提取我们想要的数据。 数据存储:将提取到的数据存储到硬盘或者内存中。比如用mysql数据库或者redis等。 那么本课程也是按照这几个步骤循序渐进的进行讲解,带领学生完整的掌握每个步骤的技术。另外,因为爬虫的多样性,在爬取的过程中可能会发生被反爬、效率低下等。因此我们又增加了两个章节用来提高爬虫程序的灵活性,分别是: 爬虫进阶:包括IP代理,多线程爬虫,图形验证码识别、JS加密解密、动态网页爬虫、字体反爬识别等。 Scrapy和分布式爬虫:Scrapy框架、Scrapy-redis组件、分布式爬虫等。 通过爬虫进阶的知识点我们能应付大量的反爬网站,而Scrapy框架作为一个专业的爬虫框架,使用他可以快速提高我们编写爬虫程序的效率和速度。另外如果一台机器不能满足你的需求,我们可以用分布式爬虫让多台机器帮助你快速爬取数据。 &nbsp; 从基础爬虫到商业化应用爬虫,本套课程满足您的所有需求! 【课程服务】 专属付费社群+每周三讨论会+1v1答疑




时钟功能 还有闹钟功能,温湿度功能,整点报时功能 你值得拥有

学生成绩管理系统(PHP + MYSQL)

做的是数据库课程设计,使用的php + MySQL,本来是黄金搭配也就没啥说的,推荐使用wamp服务器,里面有详细的使用说明,带有界面的啊!呵呵 不行的话,可以给我留言!

面试了一个 31 岁程序员,让我有所触动,30岁以上的程序员该何去何从?



获取讲师答疑方式: 在付费视频第一节(触摸命令_ALL)片头有二维码及加群流程介绍 限时福利 原价99元,今日仅需39元!购课添加小助手(微信号:itxy41)按提示还可领取价值800元的编程大礼包! 讲师介绍: 苏奕嘉&nbsp;前阿里UC项目工程师 脚本开发平台官方认证满级(六级)开发者。 我将如何教会你通过【定制脚本】赚到你人生的第一桶金? 零基础程序定制脚本开发课程,是完全针对零脚本开发经验的小白而设计,课程内容共分为3大阶段: ①前期将带你掌握Q开发语言和界面交互开发能力; ②中期通过实战来制作有具体需求的定制脚本; ③后期将解锁脚本的更高阶玩法,打通任督二脉; ④应用定制脚本合法赚取额外收入的完整经验分享,带你通过程序定制脚本开发这项副业,赚取到你的第一桶金!


原价169,限时立减100元! 系统掌握Python核心语法16点,轻松应对工作中80%以上的Python使用场景! 69元=72讲+源码+社群答疑+讲师社群分享会&nbsp; 【哪些人适合学习这门课程?】 1)大学生,平时只学习了Python理论,并未接触Python实战问题; 2)对Python实用技能掌握薄弱的人,自动化、爬虫、数据分析能让你快速提高工作效率; 3)想学习新技术,如:人工智能、机器学习、深度学习等,这门课程是你的必修课程; 4)想修炼更好的编程内功,优秀的工程师肯定不能只会一门语言,Python语言功能强大、使用高效、简单易学。 【超实用技能】 从零开始 自动生成工作周报 职场升级 豆瓣电影数据爬取 实用案例 奥运冠军数据分析 自动化办公:通过Python自动化分析Excel数据并自动操作Word文档,最终获得一份基于Excel表格的数据分析报告。 豆瓣电影爬虫:通过Python自动爬取豆瓣电影信息并将电影图片保存到本地。 奥运会数据分析实战 简介:通过Python分析120年间奥运会的数据,从不同角度入手分析,从而得出一些有趣的结论。 【超人气老师】 二两 中国人工智能协会高级会员 生成对抗神经网络研究者 《深入浅出生成对抗网络:原理剖析与TensorFlow实现》一书作者 阿里云大学云学院导师 前大型游戏公司后端工程师 【超丰富实用案例】 0)图片背景去除案例 1)自动生成工作周报案例 2)豆瓣电影数据爬取案例 3)奥运会数据分析案例 4)自动处理邮件案例 5)github信息爬取/更新提醒案例 6)B站百大UP信息爬取与分析案例 7)构建自己的论文网站案例


这门课程基于主流的java8平台,由浅入深的详细讲解了java SE的开发技术,可以使java方向的入门学员,快速扎实的掌握java开发技术!


&nbsp; &nbsp; &nbsp; &nbsp; 本课程为Python数据挖掘方向的入门课程,课程主要以真实数据为基础,详细介绍数据挖掘入门的流程和使用Python实现pandas与numpy在数据挖掘方向的运用,并深入学习如何运用scikit-learn调用常用的数据挖掘算法解决数据挖掘问题,为进一步深入学习数据挖掘打下扎实的基础。


本课程从初学者角度出发,提供了C#从入门到成为程序开发高手所需要掌握的各方面知识和技术。 【课程特点】 1 由浅入深,编排合理; 2 视频讲解,精彩详尽; 3 丰富实例,轻松易学; 4 每章总结配有难点解析文档。 15大章节,228课时,1756分钟与你一同进步!






想学好JAVA必须要报两万的培训班吗? Java大神勿入 如果你: 零基础想学JAVA却不知道从何入手 看了一堆书和视频却还是连JAVA的环境都搭建不起来 囊中羞涩面对两万起的JAVA培训班不忍直视 在职没有每天大块的时间专门学习JAVA 那么恭喜你找到组织了,在这里有: 1. 一群志同道合立志学好JAVA的同学一起学习讨论JAVA 2. 灵活机动的学习时间完成特定学习任务+每日编程实战练习 3. 热心助人的助教和讲师及时帮你解决问题,不按时完成作业小心助教老师的家访哦 上一张图看看前辈的感悟: &nbsp; &nbsp; 大家一定迫不及待想知道什么是极简JAVA学习营了吧,下面就来给大家说道说道: 什么是极简JAVA学习营? 1. 针对Java小白或者初级Java学习者; 2. 利用9天时间,每天1个小时时间; 3.通过 每日作业 / 组队PK / 助教答疑 / 实战编程 / 项目答辩 / 社群讨论 / 趣味知识抢答等方式让学员爱上学习编程 , 最终实现能独立开发一个基于控制台的‘库存管理系统’ 的学习模式 极简JAVA学习营是怎么学习的? &nbsp; 如何报名? 只要购买了极简JAVA一:JAVA入门就算报名成功! &nbsp;本期为第四期极简JAVA学习营,我们来看看往期学员的学习状态: 作业看这里~ &nbsp; 助教的作业报告是不是很专业 不交作业打屁屁 助教答疑是不是很用心 &nbsp; 有奖抢答大家玩的很嗨啊 &nbsp; &nbsp; 项目答辩终于开始啦 &nbsp; 优秀者的获奖感言 &nbsp; 这是答辩项目的效果 &nbsp; &nbsp; 这么细致的服务,这么好的氛围,这样的学习效果,需要多少钱呢? 不要1999,不要199,不要99,只要9.9 是的你没听错,只要9.9以上所有就都属于你了 如果你: 1、&nbsp;想学JAVA没有基础 2、&nbsp;想学JAVA没有整块的时间 3、&nbsp;想学JAVA没有足够的预算 还等什么?赶紧报名吧,抓紧抢位,本期只招300人,错过只有等时间待定的下一期了 &nbsp; 报名请加小助手微信:eduxy-1 &nbsp; &nbsp;


董付国系列教材《Python程序设计基础》、《Python程序设计(第2版)》、《Python可以这样学》配套视频,讲解Python 3.5.x和3.6.x语法、内置对象用法、选择与循环以及函数设计与使用、lambda表达式用法、字符串与正则表达式应用、面向对象编程、文本文件与二进制文件操作、目录操作与系统运维、异常处理结构。


文章目录Java概述何为编程什么是Javajdk1.5之后的三大版本JVM、JRE和JDK的关系什么是跨平台性?原理是什么Java语言有哪些特点什么是字节码?采用字节码的最大好处是什么什么是Java程序的主类?应用程序和小程序的主类有何不同?Java应用程序与小程序之间有那些差别?Java和C++的区别Oracle JDK 和 OpenJDK 的对比基础语法数据类型Java有哪些数据类型switc...


机器学习实战系列套餐以实战为出发点,帮助同学们快速掌握机器学习领域必备经典算法原理并结合Python工具包进行实战应用。建议学习顺序:1.Python必备工具包:掌握实战工具 2.机器学习算法与实战应用:数学原理与应用方法都是必备技能 3.数据挖掘实战:通过真实数据集进行项目实战。按照下列课程顺序学习即可! 课程风格通俗易懂,用最接地气的方式带领大家轻松进军机器学习!提供所有课程代码,PPT与实战数据,有任何问题欢迎随时与我讨论。


发现网上很多Java面试题都没有答案,所以花了很长时间搜集整理出来了这套Java面试题大全,希望对大家有帮助哈~ 本套Java面试题大全,全的不能再全,哈哈~ 一、Java 基础 1. JDK 和 JRE 有什么区别? JDK:Java Development Kit 的简称,java 开发工具包,提供了 java 的开发环境和运行环境。 JRE:Java Runtime Environ...


已经连续五年参加大厂校招、社招的技术面试工作,简历看的不下于万份 这篇文章会用实例告诉你,什么是差的程序员简历! 疫情快要结束了,各个公司也都开始春招了,作为即将红遍大江南北的新晋UP主,那当然要为小伙伴们做点事(手动狗头)。 就在公众号里公开征简历,义务帮大家看,并一一点评。《启舰:春招在即,义务帮大家看看简历吧》 一石激起千层浪,三天收到两百多封简历。 花光了两个星期的所有空闲时...


深度学习系列课程从深度学习基础知识点开始讲解一步步进入神经网络的世界再到卷积和递归神经网络,详解各大经典网络架构。实战部分选择当下最火爆深度学习框架PyTorch与Tensorflow/Keras,全程实战演示框架核心使用与建模方法。项目实战部分选择计算机视觉与自然语言处理领域经典项目,从零开始详解算法原理,debug模式逐行代码解读。适合准备就业和转行的同学们加入学习! 建议按照下列课程顺序来进行学习 (1)掌握深度学习必备经典网络架构 (2)深度框架实战方法 (3)计算机视觉与自然语言处理项目实战。(按照课程排列顺序即可)


本课程为HoloLens2开发入门教程,讲解部署开发环境,安装VS2019,Unity版本,Windows SDK,创建Unity项目,讲解如何使用MRTK,编辑器模拟手势交互,打包VS工程并编译部署应用到HoloLens上等。


本文的面试题如下: Redis 持久化机制 缓存雪崩、缓存穿透、缓存预热、缓存更新、缓存降级等问题 热点数据和冷数据是什么 Memcache与Redis的区别都有哪些? 单线程的redis为什么这么快 redis的数据类型,以及每种数据类型的使用场景,Redis 内部结构 redis的过期策略以及内存淘汰机制【~】 Redis 为什么是单线程的,优点 如何解决redis的并发竞争key问题 Red...



【数据结构与算法综合实验】欢乐连连看(C++ & MFC)案例

这是武汉理工大学计算机学院数据结构与算法综合实验课程的第三次项目:欢乐连连看(C++ & MFC)迭代开发代码。运行环境:VS2017。已经实现功能:开始游戏、消子、判断胜负、提示、重排、计时、帮助。


YOLOv3是一种基于深度学习的端到端实时目标检测方法,以速度快见长。本课程将手把手地教大家使用labelImg标注和使用YOLOv3训练自己的数据集。课程分为三个小项目:足球目标检测(单目标检测)、梅西目标检测(单目标检测)、足球和梅西同时目标检测(两目标检测)。 本课程的YOLOv3使用Darknet,在Ubuntu系统上做项目演示。包括:安装Darknet、给自己的数据集打标签、整理自己的数据集、修改配置文件、训练自己的数据集、测试训练出的网络模型、性能统计(mAP计算和画出PR曲线)和先验框聚类。 Darknet是使用C语言实现的轻型开源深度学习框架,依赖少,可移植性好,值得深入探究。 除本课程《YOLOv3目标检测实战:训练自己的数据集》外,本人推出了有关YOLOv3目标检测的系列课程,请持续关注该系列的其它课程视频,包括: 《YOLOv3目标检测实战:交通标志识别》 《YOLOv3目标检测:原理与源码解析》 《YOLOv3目标检测:网络模型改进方法》 敬请关注并选择学习!



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