Q: How to validate gmail access token on server side I want to validate gmail access token on sever 
   (ie. in action of a controller).
    I am able to get access token by below code:
now I want to validate this access_token (received by onSignIn  
function) by c# code on sever side.
I am sending email id & access_token to the sever by ajax call. 
i have no idea what to do next , please help me. Thanks in advance

function onSignIn(googleUser) {
        var profile = googleUser.getBasicProfile();  
        idToken = googleUser.Zi.access_token
        id = profile.getId();
        console.log('ID: ' + profile.getId()); 
        console.log('Name: ' + profile.getName());
        console.log('Image URL: ' + profile.getImageUrl());
        console.log('Email: ' + profile.getEmail()); 
        ValidateAccessToken(id, idToken);
    }

