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JavaScript React Basics Introducing Props Use Keys to Keep Track of Elements

can't connect to react

1)Access to script at 'https://unpkg.com/react-dom@16.7.0/umd/react-dom.development.js' (redirected from 'https://unpkg.com/react-dom@16/umd/react-dom.development.js') from origin 'http://localhost' has been blocked by CORS policy: No 'Access-Control-Allow-Origin' header is present on the requested resource. 2)GET https://unpkg.com/react-dom@16.7.0/umd/react-dom.development.js net::ERR_FAILED 3)app.js:75 Uncaught ReferenceError: ReactDOM is not defined at <anonymous>:92:1 at i (babel.min.js:24) at r (babel.min.js:24) at e.src.n.(anonymous function).l.content (https://unpkg.com/babel-standalone@6.26.0/babel.min.js:24:30503) at XMLHttpRequest.n.onreadystatechange (babel.min.js:24) (anonymous) @ app.js:75 i @ babel.min.js:24 r @ babel.min.js:24 e.src.n.(anonymous function).l.content @ babel.min.js:24 n.onreadystatechange @ babel.min.js:24 XMLHttpRequest.send (async) s @ babel.min.js:24 (anonymous) @ babel.min.js:24 o @ babel.min.js:24 u @ babel.min.js:24 f @ babel.min.js:1 (anonymous) @ babel.min.js:1

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when I open with wamp , these appears in console what is wrong with that

2 Answers

You are running into a Cross-Origin Resource Sharing issue. CORS. Here is an article that may shed some light on what is going on with your CORS. https://developer.mozilla.org/en-US/docs/Web/HTTP/CORS

thank you so much . I got it