工具类

/** * Created by admin on 2017/11/8. *///util 是一个Node.js 核心模块，提供常用函数的集合//util.inherits实现对象"原型"继承var util = require('util');function Base() {    this.name = 'base';    this.base = 1991;    this.sayHello = function () {        console.log('Hello  ' + this.name);    };}Base.prototype.showName = function () {    console.log(this.name);};function Sub() {    this.name = 'sub';}util.inherits(Sub,Base);var objBase = new Base();objBase.showName();objBase.sayHello();console.log(objBase);var objSub = new Sub();objSub.showName();//objSub.sayHello();//注意：Sub 仅仅继承了Base 在原型中定义的函数，而构造函数内部创造的 base 属 性和 sayHello 函数都没有被 Sub 继承。console.log(objSub);console.log();//util.inspect(object,showHidden/false,depth/2,color) 将任意对象转换为字符串的方法function Person(){    this.name = 'byvoid';    this.toString = function () {        return this.name;    };}var obj = new Person();console.log(util.inspect(obj));console.log(util.inspect(obj,true));console.log();//util.isArray(object) 判断object是否为数组console.log(util.isArray([]));console.log(util.isArray(new Array));console.log(util.isArray({}));console.log();//util.isRegExp(object) 判断object是否为正则表达式console.log(util.isRegExp(/some regexp/));console.log(util.isRegExp(new RegExp('another regexp')));console.log(util.isRegExp({}));console.log();//util.isDate(object):判断object是否为日期var util = require('util');console.log(util.isDate(new Date()));console.log(util.isDate(Date()));console.log(util.isDate({}));console.log();//util.isError(onject) 判断object是否为一个错误对象console.log(util.isError(new Error()));console.log(util.isError(new TypeError()));console.log(util.isError({name:'Error',message:'an error occurred'}));//这不是一个错误对象