/**    思路:在登录成功时将用户的id存进在线用户列表中的key value中链接的ws为空，并保存用户的信息.*        当跳转到聊天室时，将用户和聊天室链接的ws存进在线用户列表中的*        问题：如何在聊天室的页面时，获取到用户的id.可尝试在登录时存入cookie，当在聊天室页面时可以通过id来获取信息，并把当前的链接的ws存入key为用户id的ws中。若没有则代表改用户没有经过登录页面登录。**/package handlerimport(        "log"        "net/http"        "html/template"        _"github.com/Go-SQL-Driver/MySQL"        "database/sql"        "golang.org/x/net/websocket"        "time"        "encoding/json")type Msg struct{        //声明一个信息类型的结构体        MsgType string        MsgContent string        Id    string        To    string        ClientList string        ToId    string}type User struct{        //声明一个用户的结构体        Id    string        Nickname string        Password string        Name    string        Conn    *websocket.Conn}/*type OnlineUser struct{        //声明一个在线用户的结构体        Id int                    //这个表示key是id        Conn    *websocket.Conn        //这个表示类型是websocket        UserInfo    User//这个表示类型是websocket}*/var OnlineMap = make(map[string] *User)        //声明定一个在在线用户列表的mapvar ch = make(chan Msg)                            //这是一个channeltype Cookie struct {                //设置cookie        Name  string        Value string        Path       string        Domain     string        Expires    time.Time        RawExpires string        MaxAge   int        Secure   bool        HttpOnly bool        Raw      string        Unparsed []string // Raw text of unparsed attribute-value pairs}func IndexHandle(w http.ResponseWriter, req * http.Request){        t,err := template.ParseFiles("./view/index.html")        if err != nil{                log.Printf("no find index page")        }else{                t.Execute(w, nil)        }        //w.Write([]byte("index"))        log.Println("index")}func LoginHandle(w http.ResponseWriter, req * http.Request){        req.ParseForm()        name := req.PostFormValue("name")        pwd := req.PostFormValue("password")        if name==""&&pwd=="" {                t,_ := template.ParseFiles("./view/login.html")                t.Execute(w,nil)                return        }        var User = User{Name:name,Password:pwd}        res := login(&User)        if res {                cookie := http.Cookie{Name: "Id", Value: User.Id, Path: "/", MaxAge: 86400}    //将id 存入cookie                http.SetCookie(w, &cookie)                OnlineMap[User.Id] = &User                urlStr := "/chat?id="+User.Id                http.Redirect(w,req,urlStr,301)    //301 重定向跳转                return        }else{                t,_ := template.ParseFiles("./view/login.html")                t.Execute(w,nil)        }}func RegisterHandle(w http.ResponseWriter, req * http.Request){        err := req.ParseForm()        if err != nil {                log.Println(err)                return        }        name := req.PostFormValue("name")        password := req.PostFormValue("password")        nickname := req.PostFormValue("nickname")        res := false        if name!=""&&password!=""{                var Register = User{Name:name,Password:password,Nickname:nickname}                res = register(&Register)        }        if res {                urlStr := "/login"                http.Redirect(w,req,urlStr,301)    //301 重定向跳转                return        }else{                r,_ := template.ParseFiles("./view/register.html")                r.Execute(w, nil)        }        if err != nil{                log.Printf("no find register page")        }}type IdMsg struct{        Id string} func ChatHandle(w http.ResponseWriter, req * http.Request){        t, err := template.ParseFiles("./view/chat.html")        req.ParseForm()        Id := IdMsg{}        if len(req.Form["id"]) > 0 {                id := req.Form["id"][0]                Id.Id = id                _,isset := OnlineMap[id]                if !isset{                        http.Redirect(w,req,"/login",301)    //301 重定向跳转                }        }else{                http.Redirect(w,req,"/login",301)    //301 重定向跳转                return;        }        if err != nil {                return;        }else{                t.Execute(w, Id)        }}func Echo (ws *websocket.Conn) {        var err error        for {                var reply Msg                //user := new(OnlineUsers)                if err = websocket.JSON.Receive(ws,&reply); err != nil {                        log.Println(err)                        break                }                client_id := reply.Id                if reply.MsgType == "login"{                        OnlineMap[client_id].Conn = ws                        OnClinetJson,_ := json.Marshal(OnlineMap)                        reply.ClientList = string(OnClinetJson)                        reply.MsgContent = OnlineMap[client_id].Name+"上线了!"                        ch <- reply                }                if reply.MsgType == "say"{                        if reply.ToId == "all"{                                sendMsg := OnlineMap[client_id].Nickname + " 说：" + reply.MsgContent                                reply.MsgContent = sendMsg                                ch <- reply                        }else{                                toClientId := reply.ToId                                toClientWs := OnlineMap[toClientId].Conn                                sendMsg := OnlineMap[client_id].Nickname + " 说：" + reply.MsgContent                                reply.MsgContent = sendMsg                                SendMsg,_ := json.Marshal(reply)                                websocket.JSON.Send(toClientWs,string(SendMsg))                                        websocket.JSON.Send(ws,string(SendMsg))                                }                }        }} //mian.go中 go run handler.SendTo()func SendTO(){        for{                select{                case a := <-ch:                        for _,reg := range OnlineMap{                                SendMsg,_ := json.Marshal(a)                                websocket.JSON.Send(reg.Conn,string(SendMsg))                        }                }        }}func SuccessHandle(w http.ResponseWriter, req * http.Request){        w.Write([]byte("success"))        log.Println("success")}func ErrorHandle(w http.ResponseWriter, req * http.Request){        t, err := template.ParseFiles("./view/error.html")        if err != nil {                log.Printf("no find page")        }else{                t.Execute(w, nil)                log.Printf("find page")        }}func register(register *User) (register_res bool) {        db, err := sql.Open("mysql","go_test:jacky@/go_test?charset=utf8")        if err != nil {                return false;        }        name := register.Name        password := register.Password        nickname := register.Nickname        stmt, err := db.Prepare("INSERT user SET username = ?,pwd = ?,nickname = ?")        if err != nil{                return false;        }        _, err2 := stmt.Exec(name,password,nickname)        if err2 != nil {                register_res = false;        }else{                register_res = true;        }        return register_res}func login(user *User) (res bool){        db, err := sql.Open("mysql","go_test:jacky@/go_test?charset=utf8")        if err != nil{                log.Fatal(err)        }        name := user.Name        password := user.Password        stmtOut, err := db.Prepare("select id,nickname from user where username=? and pwd=?")    //卧槽卧槽卧槽卧槽  【我这里写的是* 所以查出来的是一条所有的字段，】        err = stmtOut.QueryRow(name,password).Scan(&user.Id,&user.Nickname)        //这里为查出来的数据赋给这个结构体,因为查出来的数据有三个字段，所以三个字段全都要在这里对应上。        if err != nil {                return false;        }        return true;}