Xamarin Forms Json 服务插入数据答案

【问题标题】：Xamarin Forms Json Service Insert DataXamarin Forms Json 服务插入数据
【发布时间】：2016-12-12 07:28:08
【问题描述】：

我想在我的应用程序中向 json 服务添加一条记录。我怎样才能通过服务网址做到这一点。这是我的代码。

CustomerModel customer = new CustomerModel();
                customer.Name = entryCompanyName.Text;
                customer.Title = entryCompanyTitle.Text;
                customer.PhoneNumber = entryTelephone.Text;
                customer.FaxNumber = entryFax.Text;
                customer.Email = entryEmail.Text;
                customer.CityId = 6444;

                string json = JsonConvert.SerializeObject(customer);
                string sContentType = "application/json";
                string path = "service url";
                HttpClient Client = new HttpClient();
                var task = Client.PostAsync(path, new StringContent(json.ToString(), Encoding.UTF8, sContentType));

我正在尝试 M. Wiśnicki 的解决方案，但我遇到了这个错误

我在添加 System.net 时没有收到错误 :( 我在哪里出错了？

【问题讨论】：

这段代码有什么问题？
找不到这些方法； GetRequestStreamAsync GetResponseAsync

标签： c# json post xamarin xamarin.forms

【解决方案1】：

这对我有用

public static async Task<string> PostEntityToApi<T>(string yourMethodUrl, T yourModel)
  {
    try
    {
        if (_httpClient == null)
        {
           _httpClient = new HttpClient { BaseAddress = new Uri(yourWebSiteUrl) };
        }

        var stringContentInput = new StringContent(JsonConvert.SerializeObject(dto), Encoding.UTF8, "application/json");

        var response = await _httpClient.PostAsync(new Uri(yourWebSiteUrl. + apiUrl), stringContentInput);

        if (!response.IsSuccessStatusCode)
        {
            throw new Exception(response.StatusCode.ToString());
        }

        var stringAsync = await response.Content.ReadAsStringAsync();

        LoggingManager.Error("Received error response: " + stringAsync);

        return stringAsync;
    }
    catch (Exception exception)
    {
        return null;
    }
 }

【讨论】：

【解决方案2】：

您可以使用WebRequest，此示例对我有用，我在我的应用程序中使用它。

这是 System.Net.WebRequest 类，在这里你可以找到doc。

 public async Task<string> PostSample(object data, string uri)
    {
        // Create an HTTP web request using the URL:  
        var request = (HttpWebRequest) WebRequest.Create(new Uri(uri));
        request.ContentType = "application/json";
        request.Method = "POST";
        var itemToSend = JsonConvert.SerializeObject(data);
        using (var streamWriter = new StreamWriter(await request.GetRequestStreamAsync()))
        {
            streamWriter.Write(itemToSend);
            streamWriter.Flush();
            streamWriter.Dispose();
        }

        // Send the request to the server and wait for the response:  
        using (var response = await request.GetResponseAsync())
        {
            // Get a stream representation of the HTTP web response:  
            using (var stream = response.GetResponseStream())
            {
                var reader = new StreamReader(stream);
                var message = JsonConvert.DeserializeObject<string>(reader.ReadToEnd());
                return message;
            }
        }
    }

【讨论】：