Question

我试图实现以下代码并在运行时遇到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)

的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

请使用＆＃39;路径＆＃39;您需要的模块。试试这个：

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

Answer 2

错误很明显，您需要指定绝对路径（而不是相对路径）

示例：

// assuming index.html is in the same directory as this script

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

你根本不需要路径 全球对象

<强> __dirname 添加于：v0.1.27

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

检查此帖子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可以提供给HTTP服务器的函数处理程序（如第2行所示）。 socket.io

__dirname vs path

Answer 3

在使用res.sendFile（）之前，您需要设置如下的静态文件目录。

var express = require('express');
var app = express();
app.use(express.static(path.join(__dirname+'your index or static files location'));
app.get('/',function(req,res){
   res.sendFile(__dirname+'index.html');
});

Nodejs：Path必须是一个字符串。收到null

3 个答案: