nodejs 文本逐行讀寫功能的實現

利用nodejs實現：逐行讀寫（從一個文件逐行復制到另外一個文件）；逐行讀取、處理和寫入（讀取一行，處理后，寫入另一個文件）

1.所需要的模塊： fs，os，readline

2.具體實現：

　a. 功能的實現：readWriteFileByLine.js

var fs = require('fs-extra'); var os = require('os'); var rl =  require('readline'); /** * 按行讀寫，無讀取內容的處理，類似單純的復制功能 * @param {string} readName * @param {string} writeName */
var readWriteFileByLine = function(readName, writeName){ var readStream = fs.createReadStream(readName); var writeStream = fs.createWriteStream(writeName); var readLine = rl.createInterface({ input: readStream, output: writeStream, terminal: true }) } /** * 按行讀寫，中間包涵對讀取的行內容的處理 * @param {string} readName * @param {string} writeName * @param {Function} callback */
var readWriteFileByLineWithProcess = function(readName,writeName,callback){ var readStream = fs.createReadStream(readName); var writeStream = fs.createWriteStream(writeName); var readLine = rl.createInterface({ input: readStream }) readLine.on('line',function(line){ var rs = callback(line); writeStream.write(rs + os.EOL); }) } exports.readWriteFileByLine = readWriteFileByLine; exports.readWriteFileByLineWithProcess = readWriteFileByLineWithProcess

　　b. 功能的調用：index.js

var rwByLine = require('./lib/readWriteFileByLine.js') //按行讀寫，對行做字符替換處理
var readName = './obj.txt'; var writeName = './rt.txt'; rwByLine.readWriteFileByLineWithProcess(readName,writeName,function(line){ var rs = line.toString().replace("\\",'\/'); return rs; }) //按行讀寫，無處理
readName = './obj.txt'; writeName = './rt1.txt'; rwByLine.readWriteFileByLine(readName,writeName);