掌握Node.js的文件系统[File System 基础]

引用文件

// 使用 `path.join()` 而不是 `+` 确保Windows也能正常工作
const path = require('path')

// 找到基于调用点的相对路径，对于命令行程序(CLI applications)非常实用
path.join(process.cwd(), 'my-dynamic-file')
// 或者
path.resolve('my-dynamic-file')

// 基于一个文件找到另外一个文件
path.join(__dirname, 'my-package-file')

读取文件

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

// read a file and pipe it to the console
fs.createReadStream(path.join(__dirname, 'my-file'))
  .pipe(process.stdout)

创建文件

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

// cat ./my-file > ./my-other-file
fs.createReadStream(path.join(__dirname, 'my-file'))
  .pipe(fs.createWriteStream(path.join(__dirname, './my-other-file')))

删除文件

const rimraf = require('rimraf')
const path = require('path')

rimraf(path.join(__dirname, './my-directory'), err => {
  if (err) throw err
})

创建目录

const mkdirp = require('mkdirp')
const path = require('path')

mkdirp(path.join(__dirname, 'foo/bar'), err => {
  if (err) throw err
})

查找文件

const readdirp = require('readdirp')
const json = require('JSONStream')
const path = require('path')

// recursively print out all files in all subdirectories
// to the command line. The object stream must be
// stringified before being passed to `stdout`.
readdirp({ root: path.join(__dirname) })
  .pipe(json.stringify())
  .pipe(process.stdout)

const findup = require('findup')
const path = require('path')

// recurse up all files relative to __dirname and find
// all `package.json` files.
findup(path.join(__dirname), 'package.json', (err, res) => {
  if (err) throw err
  console.log('dir is: ' + res)
})

const pump = require('pump')
const fs = require('fs')

// oh no, no errors are handled!
fs.createReadStream('./in.file').pipe(fs.createWriteStream('./out.file'))

// that's better, we're handing errors now
const rs = fs.createReadStream('./in.file')
const ws = fs.createWriteStream('./out.file')
pump(rs, ws, err => {
  if (err) throw err
})