In JSX, you are required to have only one top-level element in the component’s JSX code. This means that when you return JSX from a component, it must have a single outermost element encapsulating all the other elements.
Here’s an example to illustrate the requirement of a single top-level element:
import React from 'react';
function MyComponent() {
return (
<div>
<h1>Title</h1>
<p>Paragraph 1</p>
<p>Paragraph 2</p>
</div>
);
}
In this example, the <div>
element acts as the top-level element that contains the <h1>
and two <p>
elements.
However, if you try to return multiple elements without a common parent, it will result in a compilation error. For instance:
import React from 'react';
function MyComponent() {
return (
<h1>Title</h1>
<p>Paragraph 1</p>
<p>Paragraph 2</p>
);
}
The above code will generate a syntax error because there are multiple top-level elements (<h1>
, <p>
, and <p>
) without a common parent.
To address this issue, you can use a React Fragment (<>...</>
) or <React.Fragment>...</React.Fragment>
to wrap the multiple elements as a single parent element:
import React from 'react';
function MyComponent() {
return (
<>
<h1>Title</h1>
<p>Paragraph 1</p>
<p>Paragraph 2</p>
</>
);
}
In this updated code, the React Fragment acts as the single top-level element that encloses the <h1>
and two <p>
elements, allowing the code to be valid JSX.
Remember to ensure that you have only one top-level element or a single parent element when returning JSX from a component.