Dependency Injection

Introduction

• What is Dependency Injection?
• Dependency and Injection
• Requirement of the pattern and intent - Decouple Objects
• Inversion of control

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Problems Solved using Dependency Injection

• problems due to dependencies and they being reduced
• testing easy

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Code Snippet

Without DI

public engine: Engine;
public tires: Tires;
public description = 'No DI';

constructor() {
 this.engine = new Engine();
 this.tires = new Tires();
}

With DI

public description = 'DI';
constructor(public engine: Engine, public tires: Tires) { }

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