React函数组件的判定标准：接收props的函数就是函数组件吗？

Great question—this is a common point of confusion when learning React, especially when diving into HOCs! The short answer is no, not every function that accepts props as an argument qualifies as a React functional component.

Let’s break down what defines a React functional component clearly:

• It must return a React renderable output: The function’s return value has to be something React knows how to render. That includes:
  • A JSX element (like <div>, <CustomComponent />, etc.)
  • An element created via React.createElement()
  • null or undefined (which tells React to render nothing)
  • A fragment, portal, or even an array of valid React elements (supported since React 16+)

For example, this is not a React functional component—even though it takes props, it returns a raw string instead of a React element:

function BadGreeting(props) {
  return `Hey there, ${props.name}!`;
}

But this is a valid React functional component, because it returns a JSX element that React can render into the DOM:

function GoodGreeting(props) {
  return <h2>Hey there, {props.name}!</h2>;
}

To sum it up: A React functional component is a function that accepts props (and can use React Hooks for state management or side effects) and returns a React element (or renderable equivalent) that describes a piece of your application’s UI.

HOCs fit into this ecosystem as functions that take a component as input and return a new component—but the components they manipulate still follow the core rule above: they have to produce React-renderable content.

内容的提问来源于stack exchange，提问作者user9726696