使用nodejs实现JSON文件自动转Excel的工具(推荐)

const program = require('commander')

// 定义当前的版本
program
 .version(require('../package').version)

// 定义命令方法
program
 .usage('<command> [inPath] [toPath]')
 
program
 .command('start [paths...]')
 .description('Conversion from JSON to csv')
 .alias('-s')
 .action(paths => require('./command/j2c')(paths))
 
program.parse(process.argv)

if (!program.args.length) {
 program.help()
}

module.exports = (paths) => {
 // 这样就得到了输入、输出的路径了
 let [inPath, outPath] = paths
}

const co = require('co')
const prompt = require('co-prompt')

module.exports = (paths) => {
 co(function* () {
 let [inPath, outPath] = paths
 // 处理用户输入
 inPath = inPath ? inPath : yield prompt('Input file directory: ')
 outPath = outPath ? outPath : (yield prompt('Output file directory: ')) || inPath
 })
}

const Json2csvParser = require('json2csv').Parser

for(let filename in files) {
 // 同步读取文件
 let jsonData = fs.readFileSync(files[filename])
 jsonData = JSON.parse(jsonData)

 // json2csv转换
 const fields = Object.keys(jsonData[0])
 const json2csvParser = new Json2csvParser({fields})
 const csvData = json2csvParser.parse(jsonData)

 // 写入的文件名
 const outputFileName = `${outPath}/${filename}.csv`

 // 写入文件
 const err = fs.writeFileSync(outputFileName, csvData)
 if(err) {
 return console.log(err)
 } else {
 console.log(`- ${filename}.json Conversion successful！`)
 }
}

// office Excel需要 BOM 头来定义 UTF-8编码格式
const BOM = Buffer.from('\uFEFF')
const csvData = Buffer.concat([BOM, Buffer.from(csvData)])

// 不存在文件夹就创建
if(!fs.existsSync(outPath)) {
 fs.mkdirSync(outPath)
}

// 如果是对象，把对象的每一个键值对，转化成'key', 'value'的数组项
let jsonData, fields
if(Object.prototype.toString.call(jsonData) === '[object Object]') {
 jsonData = Object.keys(jsonData).map(key => ({
 key: key,
 value: jsonData[key]
 }))
 fields = ['key', 'value']
}
if(Object.prototype.toString.call(jsonData) === '[object Array]') {
 jsonData = jsonData
 fields = Object.keys(jsonData[0])
}

// 提示输出的文件目录,并退出
console.log(chalk.blue(`- Please go to check the file: ${chalk.underline(path.join(process.cwd(), outPath))}`))
process.exit()

// 使用一个非常方便的工具chalk
const chalk = require('chalk')

console.log(chalk.green('Start Conversion: '))

'use strict'
const fs = require('fs')
const path = require('path')
const chalk = require('chalk')
const glob = require('glob')
const co = require('co')
const prompt = require('co-prompt')
const Json2csvParser = require('json2csv').Parser

// 获取多文件的方法
const getMultiEntry = function (globPath) {
 let entries = {}

 glob.sync(globPath).forEach(function (entry) {
 const basename = path.basename(entry, path.extname(entry))
 entries[basename] = entry
 })

 return entries
}

module.exports = (paths) => {
 co(function* () {
 let [inPath, outPath] = paths
 // 处理用户输入
 inPath = inPath ? inPath : yield prompt('Input file directory: ')
 outPath = outPath ? outPath : (yield prompt('Output file directory: ')) || inPath

 // 遍历获取json文件
 const files = getMultiEntry(`${inPath}/*.json`)

 // 如果指定目录下没有json文件输出提示信息并退出进程
 if (!Object.keys(files).length) {
  console.log(chalk.red('\n x There is no JSON file in the specified folder'))
  process.exit()
 }

 // 开始转换文件
 console.log('\n ')
 console.log(chalk.green('Start Conversion: '))

 for(let filename in files) {
  // 同步读取文件
  let jsonData = fs.readFileSync(files[filename])
  jsonData = JSON.parse(jsonData)

  /*
  * 判断csv能接受的数据结构
  * 如果是json对象,则取key, value作为列
  * 如果是json数组，则读取第一行的所有key
  * */
  let jData, fields
  if(Object.prototype.toString.call(jsonData) === '[object Object]') {
  jData = Object.keys(jsonData).map(key => ({
   key: key,
   value: jsonData[key]
  }))
  fields = ['key', 'value']
  }
  if(Object.prototype.toString.call(jsonData) === '[object Array]') {
  jData = jsonData
  fields = Object.keys(jsonData[0])
  }

  // json格式 => csv格式
  const json2csvParser = new Json2csvParser({fields})
  const csvData = json2csvParser.parse(jData)

  // office Excel需要 BOM 头来定义 UTF-8编码格式
  const BOM = Buffer.from('\uFEFF')
  const bomCsv = Buffer.concat([BOM, Buffer.from(csvData)])

  // 写入的文件名
  const outputFileName = `${outPath}/${filename}.csv`

  // 不存在文件夹就创建
  if(!fs.existsSync(outPath)) {
  fs.mkdirSync(outPath)
  }

  // 写入文件
  const err = fs.writeFileSync(outputFileName, bomCsv)
  if(err) {
  return console.log(err)
  } else {
  console.log(chalk.green(`- ${filename}.json Conversion successful！`))
  }
 }

 // 提示输出的文件目录
 console.log('\n ')
 console.log(chalk.blue(`- Please go to check the file: ${chalk.underline(path.join(process.cwd(), outPath))}`))
 process.exit()
 })
}