React.PropTypes.shape is used in React to validate the shape of an object prop—that is, to specify what properties the object should have, and what types each property should be.

Note: PropTypes is no longer under React.PropTypes in newer React versions. Instead, you must import it from the prop-types package.

Example: Validating object shape with PropTypes.shape

import PropTypes from 'prop-types';

function UserProfile({ user }) {
  return (
    <div>
      <h2>{user.name}</h2>
      <p>Age: {user.age}</p>
    </div>
  );
}

UserProfile.propTypes = {
  user: PropTypes.shape({
    name: PropTypes.string.isRequired,
    age: PropTypes.number.isRequired
  }).isRequired
};

Explanation:

• PropTypes.shape({...}) specifies that user must be an object with:
  • a required name (string)
  • a required age (number)
• The .isRequired at the end of user itself means the user object must be passed.

Nested Shape Example:

UserProfile.propTypes = {
  user: PropTypes.shape({
    name: PropTypes.string.isRequired,
    age: PropTypes.number,
    address: PropTypes.shape({
      city: PropTypes.string,
      zip: PropTypes.string
    })
  })
};

This allows deep validation of object structures.

When to use shape:

• When a prop is an object and you want to validate its structure.
• It improves maintainability and development-time feedback.