shell
npm install --save prop-types

js
import PropTypes from 'prop-types'; // ES6
var PropTypes = require('prop-types'); // ES5 with npm

html
<!-- development version -->
<script src="https://unpkg.com/prop-types@15.6/prop-types.js"></script>

<!-- production version -->
<script src="https://unpkg.com/prop-types@15.6/prop-types.min.js"></script>

html
<!-- development version -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/prop-types/15.6.0/prop-types.js"></script>

<!-- production version -->
<script src="https://cdnjs.cloudflare.com/ajax/libs/prop-types/15.6.0/prop-types.min.js"></script>

js
import React from 'react';
import PropTypes from 'prop-types';

class MyComponent extends React.Component {
  render() {
    // ... do things with the props
  }
}

MyComponent.propTypes = {
  // You can declare that a prop is a specific JS primitive. By default, these
  // are all optional.
  optionalArray: PropTypes.array,
  optionalBigInt: PropTypes.bigint,
  optionalBool: PropTypes.bool,
  optionalFunc: PropTypes.func,
  optionalNumber: PropTypes.number,
  optionalObject: PropTypes.object,
  optionalString: PropTypes.string,
  optionalSymbol: PropTypes.symbol,

  // Anything that can be rendered: numbers, strings, elements or an array
  // (or fragment) containing these types.
  // see https://reactjs.org/docs/rendering-elements.html for more info
  optionalNode: PropTypes.node,

  // A React element (ie. <MyComponent />).
  optionalElement: PropTypes.element,

  // A React element type (eg. MyComponent).
  // a function, string, or "element-like" object (eg. React.Fragment, Suspense, etc.)
  // see https://github.com/facebook/react/blob/HEAD/packages/shared/isValidElementType.js
  optionalElementType: PropTypes.elementType,

  // You can also declare that a prop is an instance of a class. This uses
  // JS's instanceof operator.
  optionalMessage: PropTypes.instanceOf(Message),

  // You can ensure that your prop is limited to specific values by treating
  // it as an enum.
  optionalEnum: PropTypes.oneOf(['News', 'Photos']),

  // An object that could be one of many types
  optionalUnion: PropTypes.oneOfType([
    PropTypes.string,
    PropTypes.number,
    PropTypes.instanceOf(Message)
  ]),

  // An array of a certain type
  optionalArrayOf: PropTypes.arrayOf(PropTypes.number),

  // An object with property values of a certain type
  optionalObjectOf: PropTypes.objectOf(PropTypes.number),

  // You can chain any of the above with `isRequired` to make sure a warning
  // is shown if the prop isn't provided.

  // An object taking on a particular shape
  optionalObjectWithShape: PropTypes.shape({
    optionalProperty: PropTypes.string,
    requiredProperty: PropTypes.number.isRequired
  }),

  // An object with warnings on extra properties
  optionalObjectWithStrictShape: PropTypes.exact({
    optionalProperty: PropTypes.string,
    requiredProperty: PropTypes.number.isRequired
  }),

  requiredFunc: PropTypes.func.isRequired,

  // A value of any data type
  requiredAny: PropTypes.any.isRequired,

  // You can also specify a custom validator. It should return an Error
  // object if the validation fails. Don't `console.warn` or throw, as this
  // won't work inside `oneOfType`.
  customProp: function(props, propName, componentName) {
    if (!/matchme/.test(props[propName])) {
      return new Error(
        'Invalid prop `' + propName + '` supplied to' +
        ' `' + componentName + '`. Validation failed.'
      );
    }
  },

  // You can also supply a custom validator to `arrayOf` and `objectOf`.
  // It should return an Error object if the validation fails. The validator
  // will be called for each key in the array or object. The first two
  // arguments of the validator are the array or object itself, and the
  // current item's key.
  customArrayProp: PropTypes.arrayOf(function(propValue, key, componentName, location, propFullName) {
    if (!/matchme/.test(propValue[key])) {
      return new Error(
        'Invalid prop `' + propFullName + '` supplied to' +
        ' `' + componentName + '`. Validation failed.'
      );
    }
  })
};

js
  "dependencies": {
    "prop-types": "^15.5.7"
  }

js
  "dependencies": {
    "prop-types": "^15.5.7"
  },
  "peerDependencies": {
    "react": "^15.5.0"
  }

shell
# ATTENTION: Only run this if you still use React 0.14!
npm install --save react@^0.14.9 react-dom@^0.14.9

npm install --save react@^15.3.0 react-dom@^15.3.0

js
MyComponent.propTypes = {
  myProp: PropTypes.bool
};

js
// Will not work with `prop-types` package!
var errorOrNull = PropTypes.bool(42, 'myProp', 'MyComponent', 'prop');

Calling PropTypes validators directly is not supported by the `prop-types` package.
Use PropTypes.checkPropTypes() to call them.

js
// Works with standalone PropTypes
PropTypes.checkPropTypes(MyComponent.propTypes, props, 'prop', 'MyComponent');

js
const myPropTypes = {
  name: PropTypes.string,
  age: PropTypes.number,
  // ... define your prop validations
};

const props = {
  name: 'hello', // is valid
  age: 'world', // not valid
};

// Let's say your component is called 'MyComponent'

// Works with standalone PropTypes
PropTypes.checkPropTypes(myPropTypes, props, 'prop', 'MyComponent');
// This will warn as follows:
// Warning: Failed prop type: Invalid prop `age` of type `string` supplied to
// `MyComponent`, expected `number`.