gapi.client.load('plus', 'v1', function (){}) not working in Chrome,Firefox browsers

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Google

API

OAuth

I am implementing Google API Login: I am being able to login to my web app and now I am trying to fetch user details like Name, Email etc.

To fetch a user name I've a following code (got it from Google Developer's site)

gapi.client.load('plus', 'v1', function () { var request = gapi.client.plus.people.get({ 'userId': 'me' }); request.execute(function (resp) { document.getElementById('<%= hdnFldFaname.ClientID %>').value = resp.display Name; }); });

I'm trying to assign a user's name to a hiddenfiled control.. it's working only in IE(Internet Explorar) but not in Firefox, Chrome

Why this is so.. can anybody help??