fs模塊利诺，用于讀寫文件.
異步讀取代碼為：
var fs = require('fs');
fs.readFile('sample.txt','utf-8',function(err,data){
if(err){
console.log('出錯(cuò)了');
} else{
console.log(data);
}
});
同步讀取代碼為：
var fs = require('fs');
try {
var data = fs.readFileSync('sample.txt','utf-8);
console.log(data);
} catch {
console.log('出錯(cuò)了');
}
異步寫入代碼為：
var fs = require('fs');
var data = 'hello,node.js';
fs.writeFile('output.txt',data,function(err){
if(err){
console.log('出錯(cuò)了');
} else {
console.log('ok.');
}
});
同步寫入代碼為：
var fs = require('fs');
var data = 'hello,node.js';
fs.writeFileSync('output.txt',data);
注：執(zhí)行寫入代碼時(shí)，若輸出文件不存在胖缤，則會(huì)創(chuàng)建尚镰。若存在，則會(huì)覆蓋原文件內(nèi)容哪廓。
異步讀取文件信息：
var fs = require('fs');
fs.stat('samplt.txt',functon(err,stat) {
if(err) {
console.log(err);
} else {
console.log('isFile: ' + stat.isFile());
console.log('isDirectory: ' + stat.isDirectory());
if(stat.isFile()) {
console.log('size: '+ stat.size);
console.log('birth time: ' + stat.birthtime);
console.log('modified time: ' + stat.mtime);
}
});
同步讀取文件信息：
var fs = require('fs');
try {
var stat=fs.statSync('fileRead.txt');
// 是否是文件:
console.log('isFile: ' + stat.isFile());
// 是否是目錄:
console.log('isDirectory: ' + stat.isDirectory());
if (stat.isFile()) {
// 文件大小:
console.log('size: ' + stat.size);
// 創(chuàng)建時(shí)間, Date對(duì)象:
console.log('birth time: ' + stat.birthtime);
// 修改時(shí)間, Date對(duì)象:
console.log('modified time: ' + stat.mtime);
}
} catch (err) {
// 出錯(cuò)了
console.log(err);
}
流讀取文件：
var fs = require('fs');
var rs = fs.createReadStream('sample.txt','utf-8');
rs.on('data',function(chunk) {
console.log('DATA: ');
console.log(chunk);
});
rs.on('end',function() {
console.log('END');
});
rs.on('err',function(err) {
console.log('ERROR: ' + err);
});
流寫入文件：
var fs = require('fs');
var ws1 = fs.createWriteStream('output1.txt,'utf-8');
ws1.write('使用Stream寫入文本數(shù)據(jù)...\n');
ws1.write('END.');
ws1.end();
var ws2 = fs.createWriteStream('output2.txt');
ws2.write(new Buffer('使用Stream寫入二進(jìn)制數(shù)據(jù)...\n','utf-8');
ws2.write(new Buffer('END',"utf-8');
ws2.end();
流復(fù)制文件：
var fs = require('fs');
var rs = fs.createReadStream('sample.txt');
var ws = fs.createWriteStream('copied.txt');
rs.pipe(ws);
默認(rèn)情況下狗唉，當(dāng)Readable流的數(shù)據(jù)讀取完畢，end事件觸發(fā)后涡真，將自動(dòng)關(guān)閉Writable流敞曹。如果我們不希望自動(dòng)關(guān)閉Writable流，需要傳入?yún)?shù)：
readable.pipe(writable,{end:false});
建立一個(gè)http服務(wù)器：
var http = require('http');
//創(chuàng)建http server 傳入回調(diào)函數(shù)综膀，該函數(shù)接收request 和 response對(duì)象
var server = http.createServer(function(request,response){
//獲得http請(qǐng)求的method 和 url
console.log(request.method + ':' + request.url);
//將響應(yīng)200寫入response澳迫，同時(shí)設(shè)置Content-Type：text/html
response.writeHead(200,{'Content-Type' : 'text/html'});
//將http響應(yīng)的html內(nèi)容寫入response
response.end('<h1>hello world!</h1>');
});
//服務(wù)器監(jiān)聽8080端口
server.listen(8080);
//服務(wù)器啟動(dòng)成功，則打印以下內(nèi)容
console.log('Server is running at http://127.0.0.1:8080/')
建立一個(gè)http文件服務(wù)器
var fs = require('fs'),
http = require('http'),
url = require('url'),
path = require('path');
//命令行參數(shù)獲取root目錄剧劝，默認(rèn)當(dāng)前目錄
var root = path.resolve(process.argv[2] || '.');
var server = http.createServer(function(request,response){
//解析請(qǐng)求url 獲取路徑
var pathname = url.parse(request.url).pathname;
//合并路徑橄登，獲取文件真實(shí)路徑
var filepath = path.join(root,pathname);
//讀取文件信息
fs.stat(filepath,function(err,stat) {
//如果出錯(cuò)
if(!err) {
console.log('404' + request.url);
//返回404
response.writeHead(404);
//如果路徑是文件
} else if(stat.isFile()) {
console.log('200' + request.url);
//返回200
response.writeHead(200);
//文件內(nèi)容發(fā)送到 response
fs.createReadStream(filepath).pipe(response);
//如果路徑是目錄
} else if (stat.isDirectory()) {
//創(chuàng)建一個(gè)默認(rèn)文件名數(shù)組
var defpath = ['index.html','defaule.html'];
//遍歷數(shù)組
for(var i = 0; i < defpath.length; i++) {
//獲取新的文件路徑
var deffile = path.join(root,deffile[i]);
//如果路徑存在
if (fs.existsSync(deffile)) {
console.log('200' + request.url);
//返回200
response.writeHead(200);
//文件內(nèi)容發(fā)送到response
fs.createReadStream(deffile).pipe(response);
}
}
}
});
});
server.listen(8080);
console.log('Server is running at http://127.0.0.1:8080');
