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reactjsreact-proptypes

React PropTypes File type

How do I check if passed prop is of type File using Proptypes?

using PropTypes.instanceOf(File) fails with ReferenceError: File is not defined

Note: new File() constructor and typeOf someVar === File do not throw the mentioned reference error

Solution

  • Stemming from this: https://www.w3.org/TR/FileAPI/#file-section So what you could do is checking if the object has a property that is name and that is a string: something like this:

    const isFile = function(props, propName, componentName) {
  const retVal = typeof props[propName].name == 'string';
  return new Error(
        `Invalid prop ${propFullName} supplied to ${componentName}. It is not a File.`
      );
}
Component.propTypes = {
   onClick: isFile(1) 
}