import * as React from 'react'; import Cropper from 'react-cropper'; // If you choose not to use import, you need to assign Cropper to default // var Cropper = require('react-cropper').default class Demo extends React.Component { crop() { // image in dataUrl console.log((this.refs['cropper'] as any).getCroppedCanvas().toDataURL()); } render() { return ( ); } } function testCropperRef() { { // $ExpectError el can be null el.getCroppedCanvas(); if (el !== null) { // el is a cropperjs element el.getCroppedCanvas(); // el is also a React.Component instance el.props; } }} />; }