文件流

var fs = require("fs");

var readstream = fs.createReadStream(__dirname + "\stuff\readMe.txt");
var writestream = fs.createWriteStream(__dirname + "\stuff\writeMe.txt")

readstream.setEncoding("utf-8");

var str = "";
readstream.on("data", function (data) {
    str += data;
    writestream.write(data);  //写入
});

readstream.on("end", function () {
    console.log(str);
});


 /* 
var readstream = fs.createReadStream(__dirname + "\stuff\readMe.txt");
var writestream = fs.createWriteStream(__dirname + "\stuff\writeMe.txt")
readstream.pipe(writestream);
*/