node.js - Nodejs : Path must be a string. 收到空

Question

我试图实现以下代码，但在运行时遇到了 TypeError 错误。

app.js

var app = module.exports = require('express').createServer();
var io = require('socket.io').listen(app);
var path = require('path');

app.listen(3000);

app.get('/',function(req,res){
    res.sendfile(__dirname + '/index.html');
});

io.sockets.on('connection', function(socket){
    socket.emit('welcome', {text: 'Welcome!!!'});
});

错误输出:

TypeError: Path must be a string. Received null
    at assertPath (path.js:8:11)
    at posix.join (path.js:479:5)
    at exports.send (/Users/rluo/Desktop/learn/learnNode/socket.io_epxress/node_modules/express/node_modules/connect/lib/middleware/static.js:129:20)
    at ServerResponse.res.sendfile (/Users/rluo/Desktop/learn/learnNode/socket.io_epxress/node_modules/express/lib/response.js:186:3)
    at /Users/rluo/Desktop/learn/learnNode/socket.io_epxress/app.js:8:6
    at callbacks (/Users/rluo/Desktop/learn/learnNode/socket.io_epxress/node_modules/express/lib/router/index.js:272:11)
    at param (/Users/rluo/Desktop/learn/learnNode/socket.io_epxress/node_modules/express/lib/router/index.js:246:11)
    at pass (/Users/rluo/Desktop/learn/learnNode/socket.io_epxress/node_modules/express/lib/router/index.js:253:5)
    at Router._dispatch (/Users/rluo/Desktop/learn/learnNode/socket.io_epxress/node_modules/express/lib/router/index.js:280:5)
    at Object.Router.middleware [as handle] (/Users/rluo/Desktop/learn/learnNode/socket.io_epxress/node_modules/express/lib/router/index.js:45:10)

package.json:

{
    "name":"socketio_express-example",
    "version":"0.0.1",
    "private":true,
    "dependencies":{
        "socket.io":"0.8.7",
        "express":"2.5.4"
    }
}

提前致谢。

Answer 1

• 错误很明显，你需要指定一个绝对(而不是相对)路径

例子:

//假设 index.html 与该脚本位于同一目录中

res.sendFile(__dirname + '/index.html');

• 你根本不需要路径全局对象

__目录名添加于:v0.1.27

当前正在执行的脚本所在的目录的名称。有关更多详细信息 https://nodejs.org/docs/latest/api/globals.html

• 检查此线程 TypeError: Path must be a string

• 创建套接字

  var app = require('express')();
  

  var http = require('http').Server(app);

  Express 将应用程序初始化为一个函数处理程序，您可以将其提供给 HTTP 服务器(如第 2 行所示)。 socket.io

__dirname vs path