nodejs入门程序
console.log("hello world nodejs");
var http = require("http");
var port = 8888;
http.createServer(function (request, response) {
response.writeHead(200, {
'Content-Type': 'text/plain'
});
response.end('Hello World\n');
}).listen(port);
var fs = require("fs");
var fileName = "1.txt";
var data = fs.readFileSync(fileName);
console.log(data.toString());
console.log("同步方式读取文件完毕");
fs.readFile(fileName, function (err, data) {
if (err) {
console.log(err.message);
} else {
console.log(data.toString());
}
});
console.log("异步方式读取文件完毕");
var helloModule = require("./hello");
helloModule.hello("Nick");
console.log(helloModule.add(1, 2));
var person1 = new helloModule.Person("1", "张三");
console.log(person1);
person1.sayHello();
console.log("准备打开文件");
fileName = "1.txt";
fs.open(fileName, "r+", function (err, fd) {
if (err) {
console.log(err.message);
} else {
console.log("文件打开成功");
}
});
fs.stat(fileName, function (err, stats) {
if (err) {
console.log(err.message);
} else {
console.log("读取文件信息成功!");
console.log("该路径是否是文件:" + stats.isFile());
console.log("该路径是否是目录:" + stats.isDirectory());
console.log("该路径是否是块设备:" + stats.isBlockDevice());
console.log("该路径是否是字符设备:" + stats.isCharacterDevice());
console.log("该路径是否是Socket:" + stats.isSocket());
}
});
fs.writeFile("2.txt", "我是要写入的文字", function (err) {
if (err) {
console.log(err.message);
} else {
console.log("文件写入成功");
fs.readFile("2.txt", function (err, data) {
if (err) {
console.log(err.message);
} else {
console.log("文件读取完毕");
console.log(data.toString());
}
});
}
});
fileName = "2.txt";
fs.open(fileName, "r+", function (err, fd) {
if (err) {
console.log(err.message);
} else {
console.log("文件打开成功");
console.log("准备读文件");
var buf = new Buffer.alloc(1024);
fs.read(fd, buf, 0, buf.length, 0, function (err, bytes) {
let wholeData = "";
if (err) {
console.log(err);
}
if (bytes > 0) {
console.log(buf.slice(0, bytes).toString());
}
});
}
});
fs.unlink('1.txt', function (err) {
if (err) {
return console.error(err);
}
console.log("文件删除成功!");
});
console.log("我是hello.js模块,我被执行了");
function hello(msg){
console.log("hello world:" + msg);
}
function add(a,b){
return a + b;
}
function Person(id,age){
this.id = id;
this.age = age;
}
Person.prototype.sayHello = function(){
console.log("大家好,我是"+this.age + "我的id是"+this.id);
}
module.exports.hello = hello;
module.exports.add = add;
module.exports.Person = Person;