未捕获的TypeError：signalR.httpConnection不是构造函数

Question

我正在尝试使所有已连接的用户都具有身份，但它显示的错误标题为：Uncaught TypeError: signalR.httpConnection is not a constructor

对于此行：

let hubUrl = '/chatHub'
let httpConnection = new signalR.httpConnection(hubUrl);
let hubConnection = new signalR.hubConnection(httpConnection);

hubConnection.on('SetUsersOnline', usersOnline => {
    if (usersOnline.length > 0) {
        $('#onlineUsers').innerText = '';
        $.each(usersOnline, function (i, user) {

            addUserOnline(user);

        });

    }

});

hubConnection.start();

Answer 1

SignalR的语法经常更改，因此很难说出哪个版本正确和不正确。只需更新到最新的SignalR，然后尝试以下操作即可：

const connection = new signalR.HubConnectionBuilder()
                    .withUrl("/chatHub")
                    .configureLogging(signalR.LogLevel.Information)
                    .build();

connection.on('SetUsersOnline', usersOnline => {
    if (usersOnline.length > 0) {
        $('#onlineUsers').innerText = '';
        $.each(usersOnline, function (i, user) {
            addUserOnline(user);
        });
    }
});

connection.start().catch(err => console.error(err.toString()));