ReactJs vs Angular: 8 Differences You Need to Know

Parameters

ReactJs

Angular

Learning Curve

If one has a strong command of JavaScript, then learning ReactJs is smooth sailing as there are no classic templates, complicated features or dependency injection. The framework is easy to understand and working in its ecosystem will be convenient as well. Furthermore, beginners and learners can find useful resources to hone their skills and create apps successfully. However, setting up a project can be a stumbling block initially as there is no predefined structure. Make sure that you learn Redux first which is used in React applications and keep pace with the updates. 

Learning Angular will be a tough row to hoe when compared to ReactJs as it comprises a huge library. There are numerous concepts that one needs to learn which is time-consuming and complex. It offers multiple ways to solve one problem with a lot of unnecessary components. Moreover, some of its features are combined with the framework, thus, making it unavoidable to learn and use them. You have to be familiar with TypeScript, RxJs, dependency injection, etc., and also need to keep the regular updates of the changes that are frequently introduced. 

Data Binding

ReactJs supports one-way binding which implies that any changes in the model will affect the view but it won’t be the other way round. When one introduces the updates in a model, it shows the changes in the UI but alterations in UI are not evident in the model state. This singular behavior minimizes the risk of error and controls complexity. 

Angular adopts a two-way binding approach which combines the Document Object Model (DOM) values with model data. In simple terms, any updates in the model will be evident in UI elements and vice-versa. The positive point is that Angular developers need not write the codes again, making the task easier for the developer. 

Language

It is based on JavaScript and combines with JSX which is an extended XML syntax. This makes the coding easier as it almost looks like HTML, protects the coding from any injections and detects the errors instantly. JSX performs the same functions as TypeScript and is used for browser compilation via babel which is a translation code to turn it into the format that the browser can read. However, some developers can find it too complicated to comprehend. 

Although Angular is a framework, it used TypeScript which is a superset of JavaScript, making it suitable for larger projects. It is more compact than JS and easily spots mistakes in tying and convenient to navigate. Adding more to its list of benefits, TypeScript includes faster code refactoring, autocompletion and is clean and scalable. 

App Structure

There is no specific right structure in React. Developers have the complete liberty to choose the structure for the app. However, the problem is that designing the structure at the beginning of the project consumes more time and makes it difficult to start. Also, React has only ‘V’ part, i.e., View of MVC as Model and Controller are parts of other libraries. 
React is just more of a 'V' in the MVC.

It has a fixed, fully-featured MVC framework which is an addon for complex projects and divides the apps into three interconnected components. So once you learn it, it is easier to manipulate. The three layers are Model, View and Controller, popularly known as MVC. 

Document Object Model (DOM)

As ReactJs uses virtual DOM, it makes the framework super fast. All the changes in elements can be done quickly without rendering the whole DOM. This eventually adds to the performance and takes it to the new level as there is no need to change 100 items. It was this feature of ReactJs that created a buzz when it was introduced as speed is always the selling point. 

On the contrary, Angular sticks to the traditional and real DOM where the complete structure needs to be modified even if the alterations are made in one element. The entire tree structure of HTML tags is updated to finally mark the one change. 

Dependencies

There is no concept of the built-in container in ReactJs, hence, it doesn’t support dependency injection. Therefore, one has to use certain tools to inject dependencies in the ReactJS applications, such as Browserify, RequireJS, ECMAScript 6 modules, etc., which are used via ReactJs-di, Babel and more. However, the crucial task is to pick the right tool to use. 

Dependency injection provides Angular with an edge over ReactJs. This is done through parameters like $routeParams, $filter, store, and $scope. The two primary tools that make injection possible are $inject and $provide. It uses Object Oriented Programming (OOP) which implies that dependencies are written in different files. 

Directives and Templates

There is no separate division for templates and directives, hence, they need to be explained in one place. This makes it easier for readers to comprehend the codes even when they don’t know the syntax. 

It has its own directives, such as ng-bind and ng-app or you can create your own as well. The latter option paves way for better work, however, making it can be complicated to understand. 

Performance

With virtual DOM, ReactJs’ performance only gets better as the structure tree is lightweight, reducing the load on the browser. Moreover, with one-way data binding, there are no watchers, unlike Angular. 

Bidirectional data binding adversely affects the performance of Angular as it assigns more watchers to track the changes which further makes the whole process cumbersome. However, the recent updates have boosted the overall performance of Angular apps which are comparatively smaller than ReactJs apps.