使用路径。加入http://nodejs.org/docs/v0.4.10/api/path.html path.join

var path = require("path"),
    fs = require("fs");

fs.readFile(path.join(__dirname, '..', '..', 'foo.bar'));

Path.join()将为你处理开头/结尾斜杠，只是做正确的事情，你不必试图记住什么时候结尾斜杠存在，什么时候不存在。

使用路径。加入http://nodejs.org/docs/v0.4.10/api/path.html path.join

var path = require("path"),
    fs = require("fs");

fs.readFile(path.join(__dirname, '..', '..', 'foo.bar'));

Path.join()将为你处理开头/结尾斜杠，只是做正确的事情，你不必试图记住什么时候结尾斜杠存在，什么时候不存在。

你可以用不同的方法定位父文件夹下的文件，

const path = require('path');
const fs = require('fs');

// reads foo.bar file which is located in immediate parent folder.
fs.readFile(path.join(__dirname, '..', 'foo.bar'); 

// Method 1: reads foo.bar file which is located in 2 level back of the current folder.
path.join(__dirname, '..','..');


// Method 2: reads foo.bar file which is located in 2 level back of the current folder.
fs.readFile(path.normalize(__dirname + "/../../foo.bar"));

// Method 3: reads foo.bar file which is located in 2 level back of the current folder.
fs.readFile(__dirname + '/../../foo.bar');

// Method 4: reads foo.bar file which is located in 2 level back of the current folder.
fs.readFile(path.resolve(__dirname, '..', '..','foo.bar'));

如果你不确定父结点在哪里，这个会给你路径;

var path = require('path'),
    __parentDir = path.dirname(module.parent.filename);

fs.readFile(__parentDir + '/foo.bar');

如果另一个模块调用你的，你仍然想知道正在运行的主文件的位置，你可以使用@Jason的代码修改:

var path = require('path'),
    __parentDir = path.dirname(process.mainModule.filename);

fs.readFile(__parentDir + '/foo.bar');

通过这种方式，您将获得实际运行的脚本的位置。

这很好

path.join(__dirname + '/../client/index.html')

const path = require('path')
const fs = require('fs')
    fs.readFile(path.join(__dirname + '/../client/index.html'))