FB 登入實作的部分,我想大家參考官方文件應該就可以很清楚了,有範例程式碼加上全中文,我想應該沒什麼困難!

這邊想記錄的主要是 FB 客製化登入按鈕實作 FB登入的個人資料串接。

PS. 囧,當初接FB登入的時候一直拿不到使用者 email !!


備註:在以下步驟之前,要先自己參考官方文件說明創建一個facebook的APP

  1. FB客製化按鈕實作
    首先我們先使用HTML及CSS製作一個客製化的按鈕

    <button onClick="fbLogin()">你自行客製化的按鈕</button>
    

    接下來我們必須寫javascript的部分,我們需要存取使用者公開資料與email

    // javascript document
    // This is called with the results from from FB.getLoginStatus().
    function statusChangeCallback(response) {
        console.log('statusChangeCallback');
        console.log(response);
        // The response object is returned with a status field that lets the
        // app know the current login status of the persopren.
        // Full docs on the response object can be found in the documentation
        // for FB.getLoginStatus().
        if (response.status === 'connected') {
            // Logged into your app and Facebook.
            login(response.authResponse.accessToken);
        } else if (response.status === 'not_authorized') {
            // The person is logged into Facebook, but not your app.
            console.log('The person is logged into Facebook, but not your app');
        } else {
            // The person is not logged into Facebook, so we're not sure if
            // they are logged into this app or not.
            console.log("The person is not logged into Facebook");
        }
    }
    // This function is called when someone finishes with the Login
    // Button.  See the onlogin handler attached to it in the sample
    // code below.
    function checkLoginState() {
        FB.getLoginStatus(function(response) {
            statusChangeCallback(response);
        });
    }
    window.fbAsyncInit = function() {
        FB.init({
            appId      : "{{your-app-id}}",
            cookie     : true,  // enable cookies to allow the server to access 
                                // the session
            xfbml      : true,  // parse social plugins on this page
            version    : 'v2.2' // use version 2.2
        });
    };
    // Now that we've initialized the JavaScript SDK, we call
    // FB.getLoginStatus().  This function gets the state of the
    // person visiting this page and can return one of three states to
    // the callback you provide.  They can be:
    //
    // 1. Logged into your app ('connected')
    // 2. Logged into Facebook, but not your app ('not_authorized')
    // 3. Not logged into Facebook and can't tell if they are logged into
    //    your app or not.
    //
    // These three cases are handled in the callback function.
    // Load the SDK asynchronously
    (function(d, s, id) {
    var js, fjs = d.getElementsByTagName(s)[0];
    if (d.getElementById(id)) return;
    js = d.createElement(s); js.id = id;
    js.src = "//connect.facebook.net/en_US/sdk.js";
    fjs.parentNode.insertBefore(js, fjs);
    }(document, "script", "facebook-jssdk"));
    // Here we run a very simple test of the Graph API after login is
    // successful.  See statusChangeCallback() for when this call is made.
    function loginNEMI(token) {
        // 把 access_token 傳至後端再做資料拿取
        console.log("Welcome!  Fetching your information.... ");
        var xhr=new XMLHttpRequest();
        xhr.open("POST", "/login", true);
        xhr.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
        xhr.onreadystatechange=function()
        {
          if(xhr.readyState === 4 && xhr.status === 200)
          {
              if(JSON.parse(xhr.responseText).status === "ok")
                location.href="/index";
              else
                alert("something wrong!");
          }  
        };
        xhr.send("token="+token);
    }
    // custom fb login button
    function fb_login()
    {
        // FB 第三方登入,要求公開資料與email
        FB.login(function(response)
        {
            statusChangeCallback(response);
            console.log(response);
        }, {scope: 'public_profile,email'});
    }
    

    這樣就可以完成一個客製化的FB登入按鈕囉!

  2. FB登入個人資料串接
    接下來我們進一步的在後端嘗試拿取使用者所授權的個人資料
    我們可以透過上面編寫的程式碼,在後端得到使用者的 access token
    透過 graph api 去存取使用者的個人資料
    例如:
    GET  https://graph.facebook.com/me?fields=id,name,email&access_token=’+token
    graph api 會回傳:

    {
      id“: xxx”,
      name“: “xxx,
      email“: [email protected]
    }
    這樣就可以成功地拿取到使用者的資訊囉。
    另外,也可以透過 Graph API 測試工具做測試

    PS. 記得 fields 一定要填上你所要拿取的欄位,不然只能拿到基本的ID與名字。

參考資料:

https://developers.facebook.com/docs/facebook-login/web

 

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