Javascript:How to Read JSON specifically : i have used this :-

    var user = result.user;
      alert(JSON.stringify(user));


the above code has returned this data 

    {"uid":"Kbkd6QMsqIhJ4pe3QXyEUjoAohN2","displayName":"Prince Hamza","photoURL":"https://lh3.googleusercontent.com/-XdUIqdMkCWA/AAAAAAAAAAI/AAAAAAAAAAA/4252rscbv5M/photo.jpg","email":"princehamzi.mine@gmail.com","emailVerified":true,"phoneNumber":null,"isAnonymous":false,"providerData":[{"uid":"110862942226973616842","displayName":"Prince Hamza","photoURL":"https://lh3.googleusercontent.com/-XdUIqdMkCWA/AAAAAAAAAAI/AAAAAAAAAAA/4252rscbv5M/photo.jpg","email":"princehamzi.mine@gmail.com","phoneNumber":null,"providerId":"google.com"}]


but i am unable to Read this data specifically
i want it to return uid , photoURL , Name , Email ;: Particularly