在c＃中驗證Json輸出

Question

我正在嘗試通過url驗證json的輸出，所以這是一個輸出的json

{
    "response": {
        "players": [
            {
                "steamid": "76561197960435530",
                "communityvisibilitystate": 3,
                "profilestate": 1,
                "personaname": "Robin",
                "lastlogoff": 1460271265,
                "profileurl": "http://steamcommunity.com/id/robinwalker/",
                "avatar": "https://steamcdn-a.akamaihd.net/steamcommunity/public/images/avatars/f1/f1dd60a188883caf82d0cbfccfe6aba0af1732d4.jpg",
                "avatarmedium": "https://steamcdn-a.akamaihd.net/steamcommunity/public/images/avatars/f1/f1dd60a188883caf82d0cbfccfe6aba0af1732d4_medium.jpg",
                "avatarfull": "https://steamcdn-a.akamaihd.net/steamcommunity/public/images/avatars/f1/f1dd60a188883caf82d0cbfccfe6aba0af1732d4_full.jpg",
                "personastate": 0,
                "realname": "Robin Walker",
                "primaryclanid": "103582791429521412",
                "timecreated": 1063407589,
                "personastateflags": 0,
                "loccountrycode": "US",
                "locstatecode": "WA",
                "loccityid": 3961
            }
        ]
    }
}

這是一個缺少對象，但仍然有一個輸出所以我的程序拋出一個錯誤，因為它找不到我正在嘗試使用的json輸出。

{
    "response": {
        "players": [
        ]   
    }
}

這是我正在使用的代碼。 我從用戶那里獲得了SteamID，如果它不正確，它會在播放器數組中輸出沒有對象的json，但問題是如果我的程序找不到json對象o [“personastate”]它會拋出一個錯誤。 想知道如何反擊這個？ 任何幫助贊賞

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Net;
using Newtonsoft.Json;
using Newtonsoft.Json.Linq;

namespace JSONTest
{
    class Program
    {
        static void Main(string[] args)
        {
            string SteamKey = "APIKEY";
            Console.WriteLine("Give SteamID Please");
            string SteamID = Console.ReadLine();

            WebClient c = new WebClient();
            var data = c.DownloadString("http://api.steampowered.com/ISteamUser/GetPlayerSummaries/v0002/" + "?key=" + SteamKey + "&steamids=" + SteamID);
            //Console.WriteLine(data);
            JObject o = JObject.Parse(data);
            int PrivacyLevel = (int)o["response"]["players"][0]["communityvisibilitystate"];
            string username = (string)o["response"]["players"][0]["personaname"];
            string ProUrl = (string)o["response"]["players"][0]["profileurl"];

            if (PrivacyLevel == 3)
            {
                Console.WriteLine("Profile Status: Public");
            }
            else if (PrivacyLevel == 1)
            {
                Console.WriteLine("Profile Status: Private");
            }
            else
            {
                Console.WriteLine("You have typed the Steam ID Incorrectly");
            }

            Console.ReadLine(); // Don't remove you idiot
        }
    }
}

Answer 1

您可以檢查["players"]數組中是否有任何對象（我沒有測試過這段代碼）：

JObject o = JObject.Parse(data);
JArray players = (JArray)o["response"]["players"];
if(players.Count > 0){
    int PrivacyLevel = (int)players[0]["communityvisibilitystate"];
    string username = (string)players[0]["personaname"];
    string ProUrl = (string)players[0]["profileurl"];

    if (PrivacyLevel == 3)
    {
        Console.WriteLine("Profile Status: Public");
    }
    else if (PrivacyLevel == 1)
    {
        Console.WriteLine("Profile Status: Private");
    }
}
else
{
    Console.WriteLine("You have typed the Steam ID Incorrectly");
}