Angular to React Migration – Complete Guide

If you landed on this blog, chances are you must have either one of these queries:

• Is it easy to move from Angular to React?
• Should I move from Angular to React?
• Why should I migrate from Angular to React?
• What are some good reasons to migrate from Angular to React?

No, it is not easy to move from Angular to React. Yes, there are many provisions for making the Angular to React migration seamless. However, it still requires detailed precision and focused attention. Changing the frontend technology of your project is a monumental decision, and it should not be treated lightly. Before getting into how to migrate Angular to React, we should look at the why.

Why switching from Angular to React is beneficial?

Both Angular and React are leading frontend JavaScript technologies. While Angular is a complete out-of-the-box JavaScript framework, React mainly deals with the View element and is a JavaScript library.

Pain Points of using Angular

Angular is a great framework, don’t get us wrong. Many of our clients still prefer Angular. It works great for them. However, there are certain limitations of Angular that could be better for certain kinds of projects. And React proves to be a great alternative for such use cases. Here are some limitations you might be facing with Angular:

Steep Learning Curve

Even if the developer is professionally skilled in JavaScript, learning Angular can still pose a challenge and take considerable time. Angular has an ecosystem with modules, dependency injections, templates, components, and other elements. Moreover, TypeScript, with all its benefits, is still difficult to grasp versus the ease of using React with a basic understanding of JavaScript, CSS, and HTML. Hence, if your project is based on React, you could quickly replace/find developers versus that in Angular.

Abundance of Boilerplate Code

Even building the most basic simple app in Angular, you will see excessive boilerplate code needed to run the app. You will need to install many tools on your system to build a basic “Hello World” program in Angular.

DOM Dependency

Angular supports two-way data binding, which works well on modern devices. However, it can lead to serious performance lags on older devices since the browsers on such devices aren’t accustomed to doing heavy-lifting tasks of manipulating the DOM elements. Hence, they will use many of the device’s resources, making apps built on Angular perform poorly on older devices.

Benefits of shifting from Angular to React

Although more effort is required to work with React, it also provides considerable benefits such as:

Better Flexibility

Since Angular is a JavaScript framework, it defines most aspects of your web app for you. While some developers prefer such an opinionated approach, many find it limiting. Since React is a JavaScript library, it is an open playground for developers to carve out the best solution for their clients. There is more freedom in structuring your app, choosing the ideal React design pattern for the project, and using React developer tools.

Also Read: React Design Patterns: You Should Know in 2024

Component-Based UI

React follows a component-based user interface development method. You can separate the concerns for each component and create controlled tests for individual components, which makes the development and testing process easier and more efficient.

Building Blocks Approach

If you’re moving from Angular to React, you will find a cultural difference in how these technologies treat you. Angular is more of a fixed meal option, whereas React is more à la carte. You can choose the building blocks and exchange them where and when you see fit. This approach helps developers develop innovative and customized solutions for any particular problem or aspect of a client’s project.

Angular to React Migration Strategy – Best Practices

Now that we understand the benefits and challenges of migrating from Angular to React, we should focus on how to migrate Angular to React most efficiently to ensure seamless and timely migration of your existing Angular project. Here is an effective Angular-to-React Migration guide that we generally follow for our clients:

Understand the limitations of your existing Angular project

As obvious as this may sound, this is the foundation for any successful Angular to React migration project. Before shifting technologies, evaluate the shortcomings of your existing Angular project. Is there a particular aspect of your Angular app that needs to be fixed or serves your needs?

Are you sure React has a better alternative to solve this problem without adding new issues? Critical analysis is important before committing to such a change since it’s a big company decision. You should consult with a reliable ReactJS development company that can guide you about your project migration decisions.

Set Goals and Define the Scope

Now that you have made up your mind to migrate Angular to React, the next thing to do is to use the audit you carried out in the first step as a reference to what changes are needed to improvise your existing Angular app solution. If there are multiple issues or scope for improvements, you should invest some time to prioritize the changes and their urgency.

Define the scope and purpose of the migration project. Do you want to add React components to your existing Angular project? Are you planning to rewrite your Angular project in React entirely? Such questions and their answers will make a monumental difference and impact your Angular to React migration journey.

Pick the right Angular to React Migration Strategy

Depending on your project scope and goals, your chosen development agency will choose the right Angular to React migration approach after consulting with you. Having a basic understanding of these methods will help you stay on course when switching from Angular to React.

Angular to React Migration Method #1 – Rewrite Strategy

Building your Angular app from the ground up in React can be one of the most effective migration methods if you need a massive makeover and aren’t on a tight deadline. You won’t have to go through the hassle of converting Angular to React. Instead, you can start your project from scratch, defining the architecture as per your new framework and tech stack you want to use. This is ideal if the quality is your number one priority and you have a massive capital budget.

Angular to React Migration To-Do App: Plan of Action using Rewrite Method

Here are the steps you would need to take to convert your Angular-based to-do app to React:

1. Begin by learning the React ecosystem
2. Determine which Angular components or functionality should be migrated to React. You may also rewrite everything entirely
3. Begin converting Angular and template components to React components. You’ll need to rewrite the Angular HTML templates into JSX and the Angular controllers into React component classes
4. Locate and select the best Angular to React developer tool to make the conversion process easier. Before you commit to a tool, be sure you fully comprehend it. We discovered that the Angular-to-React conversion works the best most of the time
5. Next, integrate the new React components in your Angular repository using popular and reliable tools such as React2Angular or ngReact. These apps will allow you to use React components in Angular as if they were native Angular components, to begin with.  
6. Test these new components properly before committing them to the live project.

Angular to React Migration To-Do App:  Rewrite Method Step-by-Step Code Tutorial

Here’s how you’d use the rewrite method to rewrite the components of your to-do app from Angular to React:

This is the Angular component:

import { Component } from '@angular/core';
@Component({
  selector: 'app-todo-list',
  template: `
    <h1>My To-Do List</h1>
    <ul>
      <li *ngFor="let todo of todos">
        <input type="checkbox" [(ngModel)]="todo.done" (change)="markDone(todo)">
        {{ todo.title }}
      </li>
    </ul>
  `,
  styleUrls: ['./todo-list.component.css']
})
export class TodoListComponent {
  todos = [
    { title: 'Take out trash', done: false },
    { title: 'Do laundry', done: false },                                                                                         
    { title: 'Buy groceries', done: true }
  ];
  markDone(todo) {
    todo.done = !todo.done;
  }
}

Now we will create the new React service to replace this Angular component:

import React, { useState } from 'react';
function TodoList() {
  const [todos, setTodos] = useState([
    { title: 'Take out trash', done: false },
    { title: 'Do laundry', done: false },
    { title: 'Buy groceries', done: true }
  ]);
  const toggleTodo = todo => {
    setTodos(
      todos.map(item => (item.title === todo.title ? { ...item, done: !item.done } : item))
    );
  };
  return (
    <div>
      <h1>My To-Do List</h1>
      <ul>
        {todos.map(todo => (
          <li key={todo.title}>
            <input type="checkbox" checked={todo.done} onChange={() => toggleTodo(todo)} />
            {todo.title}
          </li>
        ))}
      </ul>
    </div>
  );
}

We used React hooks and JSX to rewrite the template and logic for Angular components. Also, because we are not using the Angular decorator, we will replace the Angular directives with React and JSX code.

First, let’s see how we utilized the Angular template to create an Angular component with a list of to-do items. All list items have an assigned checkbox input alongside their title. The checkbox uses a two-way data binding for the done property of each to-do item. We use the change event handler that calls the markDone() method when the user clicks the checkbox. The markDone() method is used to modify the done property’s values.

To rewrite this component from Angular to React, we will substitute the Angular template with JSX. The JSX for the React component will display an unordered list of to-do list items, just as the Angular template did for the Angular component. The only difference is we aren’t using Angular’s two-way binding. Instead, we are using a checked attribute to provide the checkbox input and the onChange method.

Also Read: React Vs React Native

Benefits and Limitations of Angular to React Rewrite Strategy

There are upsides and downsides to any Angular React Migration method. Here are some of the pros and cons of the Rewrite migration method you should know about:

When is Rewriting an ideal Angular to React Migration Technique?

Rewriting your app from scratch only makes sense when:

• You don’t need to introduce new features immediately
• When you need massive changes that require a rewrite
• When your client wants to try a different approach

Angular to React Migration Method #2 – Strangler Strategy

React, and Angular follow component-based development, which is a major benefit when shifting from Angular to React. This allows you to break your monolithic legacy Angular app into manageable components and migrate them gradually to the React frontend library. This gives you more control over the pace and focus of the entire migration strategy.

Different components can be worked upon simultaneously, which means different teams can be deployed to work on different components. Breaking down the mammoth task of migrating Angular to React can help enterprise-grade projects stagger releases and deploy migration of individual components while focusing on releasing new features.

Angular to React Migration To-Do App: Plan of Action using Strangler Method

Let’s begin by developing a strategy for converting an Angular to React To-Do App utilizing the Strangler Method:

1. Begin by identifying the sections of your Angular project that you wish to transfer to React first. Begin with a single feature or a group of features
2. Design React services to replace the nominated functionalities in your Angular app
3. Modify your Angular app’s route requests to the new React services for the specified features
4. Verify that the new React services are working properly
5. Repeat this approach for the remaining Angular components to complete the step-by-step Angular to React migration

Angular to React Migration To-Do App:  Strangler Method Step-by-Step Code Tutorial

You will need to modify the routing in your existing Angular-based to-do app to create a redirection toward new React services. To get started, you need to add the following code in the Angular router:

import { Router } from '@angular/router';
@Injectable()
export class ToDoService {
  constructor(private router: Router) {}
  addToDo(toDo: string) {
    // Redirect to the React to-do service
    this.router.navigate(['/todo/add'], { skipLocationChange: true, state: { toDo } });
  }
}

We’ve set up the redirection of the Angular components that we wish to migrate to React. We must develop the new React services to which this rerouting will point. For this project, we may utilize Express.js or any other React framework. The coding for this would look like this:

const express = require('express');
const app = express();
app.post('/todo/add', (req, res) => {
  // Create a new to-do item and store it in the database
  const toDo = req.body.toDo;
  const newToDo = new ToDo({ text: toDo });
  newToDo.save((err) => {
    if (err) {
      res.send(err);
    } else {
      // Redirect to the Angular to-do application
      res.redirect('/');
    }
  });
});
app.listen(3000, () => console.log('To-do service listening on port 3000'));

React can handle numerous requests from your Angular to-do app, allowing you to strategize and prioritize which components/features to transfer first from Angular to React. This enables you to progressively and securely transition your complete to-do app from Angular to React without risking app failure.

Also Read: Best React UI Framework You Should Know In 2024

Benefits and Limitations of Strangler Strategy

Before deciding on using the Strangler strategy for your requirements, do consider the following benefits and limitations:

When is Strangler an ideal Angular to React Migration Technique?

You are most likely to benefit from going with the Strangler migration approach when:

• You have an enterprise-grade project where you can’t risk downtime
• You want a partial/complete update to your project
• You want to introduce new features while rebranding your project
• When your client wants to try a different approach

Both Rewrite and Strangler migration methods come with concerning limitations or commitments. Suppose you are still struggling to choose a method between the two to migrate from Angular to React. In that case, you should consult with a professional ReactJS Development Company to guide your migration roadmap.

Wrapping up!

This is your ultimate Angular to React migration guide to refer to if you have an existing Angular app that you plan to shift to React. Keep in mind that a complete rewrite is only needed when you need a massive makeover for your project, and you can always migrate your project using the Strangler method gradually. Each project is unique and has different requirements; hence you should be fully aware of all the possible options before you choose one.