Legacy React APIs

Legacy APIs

• Children lets you manipulate and transform the JSX received as thechildren prop.See alternatives.
• cloneElement lets you create a React element using another element as a starting point.See alternatives.
• Component lets you define a React component as a JavaScript class.See alternatives.
• createElement lets you create a React element. Typically, you’ll use JSX instead.
• createRef creates a ref object which can contain arbitrary value.See alternatives.
• forwardRef lets your component expose a DOM node to parent component with aref.
• isValidElement checks whether a value is a React element. Typically used withcloneElement.
• PureComponent is similar toComponent, but it skip re-renders with same props.See alternatives.

Removed APIs

These APIs were removed in React 19:

• createFactory: use JSX instead.
• Class Components:static contextTypes: usestatic contextType instead.
• Class Components:static childContextTypes: usestatic contextType instead.
• Class Components:static getChildContext: useContext instead.
• Class Components:static propTypes: use a type system likeTypeScript instead.
• Class Components:this.refs: usecreateRef instead.