Please explain conditional rendering in React.

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Today’s content: Please explain conditional rendering in React.

Conditional rendering in React refers to the technology of deciding whether to render (or what content to render) based on specific conditions. This enables you to dynamically show or hide components, elements, or content based on your app’s state and logic.

Conditional rendering is usually implemented using one of the following methods:

  1. Use JavaScript expressions: In the render method of a React component, you can use JavaScript conditional statements (such as if statements or conditional operators) to decide what content to render. This allows you to choose what to render based on the component’s internal state or props.
render() {
  const isLoggedIn = this.state.isLoggedIn;
  
  return (
    <div>
      {isLoggedIn ? <UserGreeting /> : <GuestGreeting />}
    </div>
  );
}
  1. Use the logical AND operator & amp; & amp;: When you only need to determine whether to render content based on one condition, you can use the logical AND operator. If the condition is true, the following content will be rendered.
render() {
  const isUserLoggedIn = this.props.userLoggedIn;
  
  return (
    <div>
      {isUserLoggedIn & amp; & amp; <UserGreeting />}
    </div>
  );
}
  1. Use the conditional operator ?: This is a ternary conditional operator that returns different content depending on the condition.
render() {
  const userRole = this.props.userRole;
  
  return (
    <div>
      {userRole === 'admin' ? <AdminDashboard /> : <UserDashboard />}
    </div>
  );
}
  1. Use conditional rendering outside the if-else statement: Use the if-else statement outside the render method, then Insert the result into render. This is useful for complex conditional logic.
renderUserGreeting() {
  if (this.props.isLoggedIn) {
    return <UserGreeting />;
  } else {
    return <GuestGreeting />;
  }
}

render() {
  return (
    <div>
      {this.renderUserGreeting()}
    </div>
  );
}

React’s conditional rendering enables you to create interactive UIs with dynamic behavior. By dynamically selecting what to render based on your app’s state and data, you can build expressive and flexible user interfaces.

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