Note.js的stream用法一例

 

Note.js，用stream读取文件的内容，注意decoder的用法

const fs = require('fs');

 

var rr = fs.createReadStream('data\foo.txt');

 

// Pull off a header delimited by

// use unshift() if we get too much

// Call the callback with (error, header, stream)

const StringDecoder = require('string_decoder').StringDecoder;

function parseText(stream, callback) {

stream.on('error', callback);

stream.on('readable', onReadable);

var decoder = new StringDecoder('utf8');

var header = '';

function onReadable() {

var chunk;

while (null !== (chunk = stream.read())) {

var str = decoder.write(chunk);

console.log(str);

}

}

}

 

parseText(rr,

    function(source, header, stream )

    {

        console.write(header);

    }

 

);