最好的c#语法/习语，从Facebook读取好友数组

本文关键字：Facebook 读取 好友 数组 习语 语法 | 更新日期: 2023-09-27 18:01:26

在c#中，我只是从FB api中抓取"/me/friends"，

private void FacebookFriends()
    {
    FB.API("/me/friends", HttpMethod.GET, FBAPIFriendsCallback);
    }
private void FBAPIFriendsCallback(FBResult response)
    {
    // (error handling here - no problem)
    // ugly code...
    var dict = Json.Deserialize(response.Text)
        as Dictionary<string,object>;
    var friendList = new List<object>();
    friendList = (List<object>)(dict["data"]);
    int _friendCount = friendList.Count;
    // ugly code...
    // (example shows getting one item, would loop through all)
    string id = getDataValueForKey(
          (Dictionary<string,object>)(friendList[0]), "id" );
    string name = getDataValueForKey(
          (Dictionary<string,object>)(friendList[0]), "name" );
    }

注意这段非常非常丑陋的代码——还有什么更优雅的方式来写呢?欢呼声

事实上，根据swazza下面的评论，这里是完整的代码段落:

using UnityEngine;
using System.Collections;
using System.Collections.Generic;
using Parse;
using System;
using Facebook;
using System.Threading.Tasks;
using System.IO;
using System.Linq;
using Facebook.MiniJSON;

public class ParseLinkOps : MonoBehaviour
  {
  ...
  public void GetFriendsFromFBThenMatch()
    {
    FB.API("/me/friends", HttpMethod.GET, _cbFriends);
    // FB calls at
    // https://developers.facebook.com/docs/unity/reference/current
    }
  private void _cbFriends(FBResult response)
    {
    // goal: given the json result from the cloud,
    // create a List<string> containing only the FacebookID "id" numbers
    if ( ! String.IsNullOrEmpty(response.Error) )
      { // .. error handling .. return; }
    var dict = Json.Deserialize(response.Text)
            as Dictionary<string,object>;
    var friendList = new List<object>();
    friendList = (List<object>)(dict["data"]);
    int _friendCount = friendList.Count;
    Debug.Log("Found friends on FB, _friendCount ... " +_friendCount);
    // so, convert that complex array of FB objects,
    // to simply an array of "id" strings
    // use very ugly code but assume someone on SO knows better later :-)
    List<string> friendIDsFromFB = new List<string>();
    for ( int k=0; k<_friendCount; ++k)
      {
      string friendFBID =
        getDataValueForKey( (Dictionary<string,object>)(friendList[k]), "id");
      string friendName =
        getDataValueForKey( (Dictionary<string,object>)(friendList[k]), "name");
      Debug.Log( k +"/" +_friendCount +" " +friendFBID +" " +friendName);
      friendIDsFromFB.Add( friendFBID );
      }
    // we're done, the list is in friendIDsFromFB
    StartCoroutine( _match( friendIDsFromFB ) );
    }
  ...
  }

最好的c#语法/习语，从Facebook读取好友数组

如何使用linq扩展?

var dict = new Dictionary<string, object>();
var friend = dict
            .Where(s => s.Key.Equals("data"))
            .Select(s => new { Id = s.Key, Name = s.Value })
            .First();
var friendId = friend.Id;
var friendName = friend.Name;

下面是一个linq扩展，用于迭代可枚举对象并对每个元素执行操作- 

public static void Execute<TSource>(this IEnumerable<TSource> source, Action<TSource> actionToExecute)
{
    if (source.Count() > 0)
    {
        foreach (var item in source)
        {
            actionToExecute(item);
        }
    }
}

编辑:所以我理解你在Unity游戏引擎中使用这个。我已经很久没有开发Unity了。很高兴知道他们现在支持Linq了。这是我写的获取好友id的代码。有一些代码是ASP特有的。但是linq部分应该在任何地方工作- 

// Use ASP.Net's Javascript serializer to desrialize the json response received from 
// call to graph.facebook.com/me/friends
var jsSerializer = new JavaScriptSerializer();
var jsonString = "{ '"data'": [ { '"name'": '"name1'", '"id'": '"id1'" }, { '"name'": '"name2'", '"id'": '"id2'" } ] }";
// Deserialize the json to type - Dictionary<string, object>
var dict = jsSerializer.Deserialize(jsonString, typeof(Dictionary<string, object>)) as Dictionary<string, object>;
/*Code upto here is specific to ASP.Net - At this point, be it ASP.Net or Unity, we have a dictionary that contains a key "data" which again contains a dictionaries of name value pairs*/
// The code from below is Linq and should work on Unity as well.
var friendIds = (dict["data"] as ArrayList)                     // Convert the "data" key of the dictionary into its underlying type (which is an ArrayList in this case)
                .Cast<Dictionary<string, object>>()             // ArrayList is not generic. Cast it to a generic enumerable where each element is of type Dictionary<string, object> 
               .Select(s =>
                            {
                                // Each element in the cast enumerable is of type dictionary.
                                // Each dictionary has two keys - "id" and "name" that correspond to the id and name properties 
                                // of the json response received when calling graph.facebook.com/me/friends.
                                // check - https://developers.facebook.com/tools/explorer/145634995501895/?method=GET&path=me%2Ffriends&version=v2.0
                                // Because we only want Ids, fetch the value corresponding to the "id" key
                                object id = null;
                                if (s.TryGetValue("id", out id))
                                {
                                    return id.ToString();
                                }
                                return string.Empty;
                            });

我添加了冗长的注释，使代码更容易解释。如果去掉注释，代码就会简洁。但是，这比普通的for循环性能差。

相关文章：