转换从Resful Web服务返回的JSON响应

时间:2015-12-07 16:14:22

标签: c# asp.net json web-services

我的RESTFUL Web服务和我的Web应用程序中有这两个类

public class Service
{
    public int ID { get; set; }
    public int HCode { get; set; }
    public int HUserID { get; set; }
    public string PatientNID { get; set; }
    public List<Document> DocumentList { get; set; }
    public int ServiceTypeID { get; set; }
    public string TestName { get; set; }
    public string Comment { get; set; }
    public DateTime Date { get; set; }
}

public class Document
{
    public int ID { get; set; }
    public int ServiceID { get; set; }
    public string FileName { get; set; }
    public string Extension { get; set; }
    public byte[] ByteDocument { get; set; }
}

这是收发对象并在网络服务中发回列表

public List<Serivce> GetServiceByHUserID(Service service)
    {
        SqlCommand cmd = new SqlCommand(
              "SELECT *"
            + " FROM TransactionHistory"
            + " WHERE UserID = @HUserUserIDParam"
            , con);
        cmd.Parameters.Add(
        "@HUserUserIDParam", SqlDbType.NVarChar).Value = service.HUserID;

        return GetServiceResponse(cmd);
    }

private List<Service> GetServiceResponse(SqlCommand cmd)
    {
            List<Service> serviceList = new List<Service>();
        try
        {
            // Filling Data
              ....
        }
            return serviceList;
        }
        catch (Exception e) { return null; }
        finally { con.Close(); }
    }

这是Web应用程序中的发送对象和接收列表

private List<Service> GetServiceListResponse(HttpWebRequest request
        , Service service)
    {
        try
        {
            var json = new JavaScriptSerializer().Serialize(service);
            request.Method = "POST";
            request.ContentType = "application/json";
            request.ContentLength = json.Length;
            StreamWriter requestWriter = new StreamWriter(request.GetRequestStream(),
                System.Text.Encoding.ASCII);
            requestWriter.Write(json);
            requestWriter.Close();

            WebResponse webResponse = request.GetResponse();
            Stream webStream = webResponse.GetResponseStream();
            StreamReader responseReader = new StreamReader(webStream);
            string response = responseReader.ReadToEnd();
            JavaScriptSerializer serializer = new JavaScriptSerializer();
            // ERROR HERE
            dynamic item = serializer.Deserialize<List<Service>>(response);
            // ERROR HERE
            responseReader.Close();
            return item;
        }
        catch (Exception e) { return null; }
    }

当我尝试返回List&lt; .Service&gt;作为一个JSON对象并反序列化它我得到了该错误

这是例外

  

无法将'System.String'类型的对象转换为'System.Byte []'

1 个答案:

答案 0 :(得分:0)

我找到了解决方案

这只是改变我在序列化和反序列化中使用的类(在.NET中构建的类称为 JavaScriptSerializer

JavaScriptSerializer ()到 JsonConvert

在Github上发布:https://github.com/JamesNK/Newtonsoft.Json/releases

NuGut上的最新软件包:安装包Newtonsoft.Json

Newtonsoft网站:http://www.newtonsoft.com/json

在引用dll或下载软件包之后,引用代码中的dll(在.cs类中):

using Newtonsoft.Json;

其他参考资料:

using System.IO;
using System.Text;

在发送和使用 UTF8 编码之前序列化json对象:

string json = JsonConvert.SerializeObject(service);
request.Method = "POST";
request.Method = "POSt";
request.ContentType = "application/json";
request.ContentLength = Encoding.UTF8.GetByteCount(json);
StreamWriter requestWriter = new StreamWriter(request.GetRequestStream(), new UTF8Encoding(false));
requestWriter.Write(json);
requestWriter.Close();

在收到回复后反序列化json对象:

List<Service> serviceList = JsonConvert.DeserializeObject<List<Service>>(response);