“SyntaxError: Unexpected token < in JSON at position 0”

Question

In a React app component which handles Facebook-like content feeds, I am running into an error:

Feed.js:94 undefined \"parsererror\" \"SyntaxError: Un

Answer 1

I had the same error message following a tutorial. Our issue seems to be 'url: this.props.url' in the ajax call. In React.DOM when you are creating your element, mine looks like this.

ReactDOM.render(
    ,
    document.getElementById('content')
);

Well, this CommentBox does not have a url in its props, just data. When I switched url: this.props.url -> url: this.props.data, it made the right call to the server and I got back the expected data.

I hope it helps.