3-fs

const fs = require('fs');

let ws = fs.createWriteStream('./data1.txt')            // 流式写入，频繁写入的

ws.write('床前明月光\n')

ws.write('凝是地上霜\n')

ws.write('举头望明月\n')

ws.write('低头思故乡\n')

ws.close()