9、TypeScript中的命名空间

命名空间：

　　在代码量较大的情况下，为了避免各种变量名相冲突，可以将相识的功能的函数、类、接口等放置在命名空间中。

　　同java的包、.net的命名空间一样，Typescript的命名空间可以将代码包裹起来，只对外暴露需要访问的对象，命名空间内的对象通过export暴露。

命名空间和模块的区别：

　　命名空间：内部模块，主要用于组织代码，避免命名冲突。

　　模块：ts的外部模块的简称，侧重代码的复用，一个模块里可能会有多个命名空间。

在modules中定义一个文件name.ts

export namespace A{
  interface Animal{
    name:string;
    eat():void;
  }
  export class Dog implements Animal{
    name:string;
    constructor(theName:string){
      this.name = theName
    }
    eat(){
      console.log(`${this.name}在吃狗粮`);
    }
  }

  export class Cat implements Animal{
    name:string;
    constructor(theName:string){
      this.name = theName
    }
    eat(){
      console.log(`${this.name}在吃猫粮`);
    }
  }
}


export namespace B{
  interface Animal{
    name:string;
    eat():void;
  }
  export class Dog implements Animal{
    name:string;
    constructor(theName:string){
      this.name = theName
    }
    eat(){
      console.log(`${this.name}在吃狗粮`);
    }
  }

  export class Cat implements Animal{
    name:string;
    constructor(theName:string){
      this.name = theName
    }
    eat(){
      console.log(`${this.name}在吃猫粮`);
    }
  }
}

namespace.js中引入并使用

import {A,B} from './modules/name'

var d = new A.Dog('哈士奇小黑');
d.eat()

var c = new B.Cat('小花');
c.eat()

export namespace A{

interface Animal{

name:string;

eat():void;

}

export class Dog implements Animal{

name:string;

constructor(theName:string){

this.name = theName

}

eat(){

console.log(`${this.name}在吃狗粮`);

}

}

export class Cat implements Animal{

name:string;

constructor(theName:string){

this.name = theName

}

eat(){

console.log(`${this.name}在吃猫粮`);

}

}

}

export namespace B{

interface Animal{

name:string;

eat():void;

}

export class Dog implements Animal{

name:string;

constructor(theName:string){

this.name = theName

}

eat(){

console.log(`${this.name}在吃狗粮`);

}

}

export class Cat implements Animal{

name:string;

constructor(theName:string){

this.name = theName

}

eat(){

console.log(`${this.name}在吃猫粮`);

}

}

}