InversifyJS輕量級(jí)反轉(zhuǎn)控件容器

InversifyJS 一個(gè)強(qiáng)大而輕量級(jí)的反轉(zhuǎn)控件 (IoC) 容器，適用于由TypeScript編寫(xiě)的JavaScript和Node.js應(yīng)用。它使用類構(gòu)造函數(shù)去定義和注入它的依賴。InversifyJS API友好易懂，鼓勵(lì)對(duì)OOP和IoC最佳實(shí)踐的應(yīng)用。

InversifyJS有4個(gè)主要目標(biāo):

1. 允許JavaScript開(kāi)發(fā)人員編寫(xiě)遵循 SOLID 原則的代碼。

2. 促進(jìn)并鼓勵(lì)遵守最佳的面向?qū)ο缶幊毯鸵蕾囎⑷雽?shí)踐。

3. 盡可能少的運(yùn)行時(shí)開(kāi)銷。

4. 提供藝術(shù)編程體驗(yàn)和生態(tài)。

使用

步驟 1：定義接口

// file interfaces.ts

export interface Warrior {
    fight(): string;
    sneak(): string;
}

export interface Weapon {
    hit(): string;
}

export interface ThrowableWeapon {
    throw(): string;
}

步驟 2：定義依賴

// file entities.ts

import { injectable, inject } from "inversify";
import "reflect-metadata";
import { Weapon, ThrowableWeapon, Warrior } from "./interfaces";
import { TYPES } from "./types";

@injectable()
class Katana implements Weapon {
    public hit() {
        return "cut!";
    }
}

@injectable()
class Shuriken implements ThrowableWeapon {
    public throw() {
        return "hit!";
    }
}

@injectable()
class Ninja implements Warrior {

    private _katana: Weapon;
    private _shuriken: ThrowableWeapon;

    public constructor(
	    @inject(TYPES.Weapon) katana: Weapon,
	    @inject(TYPES.ThrowableWeapon) shuriken: ThrowableWeapon
    ) {
        this._katana = katana;
        this._shuriken = shuriken;
    }

    public fight() { return this._katana.hit(); }
    public sneak() { return this._shuriken.throw(); }

}

export { Ninja, Katana, Shuriken };

步驟 3：創(chuàng)建并配置 IOC 容器

// file inversify.config.ts

import { Container } from "inversify";
import { TYPES } from "./types";
import { Warrior, Weapon, ThrowableWeapon } from "./interfaces";
import { Ninja, Katana, Shuriken } from "./entities";

const myContainer = new Container();
myContainer.bind<Warrior>(TYPES.Warrior).to(Ninja);
myContainer.bind<Weapon>(TYPES.Weapon).to(Katana);
myContainer.bind<ThrowableWeapon>(TYPES.ThrowableWeapon).to(Shuriken);

export { myContainer };

步驟4：依賴解析

import { myContainer } from "./inversify.config";
import { TYPES } from "./types";
import { Warrior } from "./interfaces";

const ninja = myContainer.get<Warrior>(TYPES.Warrior);

expect(ninja.fight()).eql("cut!"); // true
expect(ninja.sneak()).eql("hit!"); // true