從函數的函數調用javascript中

Question

function getSenderName(senderId) { 
     var __name; 
     // Get user's first name from the User Profile API 
     // and include it in the greeting 
     request({ 
     url: "https://graph.facebook.com/v2.6/" + senderId, 
     qs: { 
      access_token: process.env.PAGE_ACCESS_TOKEN, 
      fields: "first_name" 
     }, 
     method: "GET" 
     }, function(error, response, body) { 
     if (error) { 
      console.log("Error getting user's name: " + error); 
     } else { 
      var bodyObj = JSON.parse(body); 
      __name = bodyObj.first_name; 
      console.log("1.SenderId : " + senderId + " Name : " + __name); 
     } 
     }); 
     console.log("2.SenderId : " + senderId + " Name : " + __name); 
     return __name; 
    } 

與上面的代碼中，我得到

1.SenderId : 1234 Name : Vinay 
2.SenderId : 1234 Name : Undefined 

任何人可以幫助我如何訪問變量，它是這樣的嵌套函數內部

Answer 1

只爲你裏面怎麼訪問變量要知道，

function getSenderName(senderId, callback) { 
    function(){ 
    var variable ; 
    //some stuff 
    callback(variable, otherArgs ...); 
    } 
} 

回調做的完全相同的工作..