Conditional Rendering Based on States

Hello, students! In the previous topic, we learned about naming patterns for handling events. Today, let’s delve into conditional rendering based on states.

What is Conditional Rendering?

Conditional rendering is the ability to render elements or content conditionally, based on data or states.

Why Use Conditional Rendering?

Conditional rendering is an essential skill for creating reactive user interfaces. By learning to use conditional rendering, you can create components that respond to changes in data or states.

How to Use Conditional Rendering Based on States?

To use conditional rendering based on states, we can use the condition property of the component.

The condition property takes a boolean expression that determines whether the component should be rendered.

Example of Conditional Rendering Based on States

Let’s see an example of how to use conditional rendering based on states:

class App extends React.Component {
  state = {
    isLoggedIn: false,
  };

  render() {
    return (
      <div>
        {this.state.isLoggedIn ? (
          <h1>Welcome!</h1>
        ) : (
          <h1>You are not logged in.</h1>
        )}
      </div>
    );
  }
}

In this example, the App component has a state called isLoggedIn. It renders an h1 with the message “Welcome!” if the isLoggedIn state is true. It renders an h1 with the message “You are not logged in.” if the isLoggedIn state is false.

Other Methods for Conditional Rendering

In addition to the condition property, we can use other methods for conditional rendering in React components.

• The render() method: We can use the render() method to conditionally return an element or content.
• The ternary operator: We can use the ternary operator to conditionally render an element or content.

Conclusion

Conditional rendering is an essential skill for creating reactive user interfaces.

By learning to use conditional rendering, you can create components that respond to changes in data or states.