Question

我正在尝试使用typescript创建从服务器到客户端的socket.io连接，我需要在构造函数中定义“socket”对象，以便对象可以使用套接字向客户端发送数据。但是，当编译为javascript时，套接字对象不会被定义为该类的变量，这会阻止它被调用。

这是打字稿。

导出类上传{

directory = "./data";
socket: Socket;

constructor(socket:Socket) {
    this.socket = socket;
}

public upload(req:express.Request, res) {
                this.socket.emit('fileReceivedConfirmation', {
                    successful:true,
                    filePath: filePath,
                    originalName: originalFileName
                });
    }

这是相应的javascript

function Upload(socket) {
    this.directory = "./data";
    this.socket = socket;
}

Upload.prototype.upload = function (req, res) {
      this.socket.emit('fileReceivedConfirmation', {
                successful: true,
                filePath: filePath,
                originalName: originalFileName
            });
}

套接字变量未在编译的Javascript中的任何位置定义 - 当函数调用socket时会产生此错误。

C:\Users\Me\WebstormProjects\Core\lib\Upload.js:43
            this.socket.emit('fileReceivedConfirmation', {
                        ^
TypeError: Cannot call method 'emit' of undefined

Answer 1

尝试更改以下代码

io.sockets.on('connection', function (socket) {
    this.socket = socket;
});

到此

io.sockets.on('connection', (socket:any):void => {
        this.socket = socket;
    });

Answer 2

我将变量转换为静态并且有效：

directory = "./data";
static socket:Socket;

constructor(socket:Socket) {
    console.log("Creating socket");
    Upload.socket = socket;
}

全局变量未在Typescript中定义

2 个答案: