What Are Inline Conditional Expressions in React.js

Inline conditional expressions in React

Inline conditional expressions in React allow you to conditionally render elements based on certain conditions. They are used within JSX to dynamically include or exclude parts of the UI based on the evaluation of an expression. This is often achieved using the ternary operator (condition ? trueValue : falseValue) or logical && operator.

Here's how you can use inline conditional expressions in React:

Using the Ternary Operator

You can use the ternary operator to conditionally render elements based on a condition. For example.

function Greeting(props) {
  const isLoggedIn = props.isLoggedIn;
  return (
    <div>
      {isLoggedIn ? <UserGreeting /> : <GuestGreeting />}
    </div>
  );
}

In this example, if isLoggedIn is true, the <UserGreeting /> component will be rendered; otherwise, <GuestGreeting /> will be rendered.

Using Logical && Operator

You can also use the logical && operator to conditionally render elements. If the condition before && is true, the element after && will be rendered; otherwise, nothing will be rendered. For example.

function Greeting(props) {
  const isLoggedIn = props.isLoggedIn;
  return (
    <div>
      {isLoggedIn && <UserGreeting />}
    </div>
  );
}

In this example, if isLoggedIn is true, the <UserGreeting /> component will be rendered; otherwise, nothing will be rendered.

Using Conditional Statements

You can use regular JavaScript conditional statements outside of JSX to conditionally render elements. For example.

function Greeting(props) {
  const isLoggedIn = props.isLoggedIn;
  let greetingComponent;
  if (isLoggedIn) {
    greetingComponent = <UserGreeting />;
  } else {
    greetingComponent = <GuestGreeting />;
  }
  return (
    <div>
      {greetingComponent}
    </div>
  );
}

In this example, greetingComponent is assigned the appropriate component based on the value of isLoggedIn, and then it is rendered inside JSX.

These are some of the common ways to use inline conditional expressions in React to conditionally render elements based on certain conditions. Choose the method that fits best with your code structure and readability requirements.