Question

我试图用一些API数据填充组合框，但JSON出现问题。

API调用：

string URL = @"https://localhost:44306/api/user/68/all";
            Uri Urladdress = new Uri(URL);
            HttpWebRequest request = WebRequest.Create(Urladdress) as HttpWebRequest;
            request.Headers["X-AccessToken"] = AccessToken;
            request.Method = "GET";
            request.ContentType = "application/json";
            string results = string.Empty;
            HttpWebResponse response;
            using (response = request.GetResponse() as HttpWebResponse)
            {
                StreamReader reader = new StreamReader(response.GetResponseStream());
                results = reader.ReadToEnd();
            }

            List<Json> lsObj = JsonConvert.DeserializeObject<List<Json>>(results);

            foreach (Json obj in lsObj)
            {
                for (int i = 0; i < obj.Users.Count(); i++)
                {
                    friends.Items.Add(obj.Users[i].UserId);
                }
            }

JSON类：

    public class Json
    {
        public List<User> Users { get; set; }
    }

    public class User
    {
        public int UserId { get; set; }
        public string Username { get; set; }
        public string FullName { get; set; }
        public object Password { get; set; }
    }

API响应：

{"Users":[{"UserId":68,"Username":"Rob","FullName":"Rob test","Password":null},{"UserId":69,"Username":"Test","FullName":"TestRob","Password":null}]}

Visual Studio在UserId的obj.Users.UserId上返回错误

Screenshot error message

'User []'不包含'UserID'的定义，并且不可访问扩展方法'UserId'接受类型为'User []'的第一个参数可以找到（您是否缺少using指令或程序集参考？）

是否有解决此问题的简单方法？

Answer 1

您正试图从集合Users中访问User属性，请尝试

            foreach (Json obj in lsObj)
            {
               foreach (User user in lsObj.Users)
               {             
                   friends.Items.Add(user.UserId);
               }
            }

Answer 2

因为有一个数组..您需要一个索引

obj.Users[0].UserId  //will get you 68

obj.Users[1].UserId //will get you 69

考虑从更改模型

User[] Users {get; set;}

收件人

List<User> Users {get; set;}

OR

我建议您在第二个循环中使用for循环（如果采用此路线，则不要理会您的模型）

for(int i = 0; i < obj.Users.Count(); i++)
{
    friends.Items.Add(obj.Users[i].UserId);
}

如何用JSON API填充组合框

2 个答案: