HttpClient 后调用

Question

我想使用 HttpClient 进行 REST POST 调用。我一直有错误 - 'RestCall.PostRestCall(string, string, string, string)'：并非所有代码路径都返回一个值'

下面是我的代码。 它的意思是接收 baseUrl、contentType、requestBody、httpMethod； 作为输入参数并返回响应状态码、状态描述和响应内容。

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Threading.Tasks;

namespace RestPostCall
{
    public class RestCall
    {
        public static string PostRestCall(string baseURL, string httpMethod, string contentType, string requestBody)
        {
            HttpClient client = new HttpClient();
            client.BaseAddress = new Uri(baseURL);

            // Add an Accept header for JSON format.
            client.DefaultRequestHeaders.Accept.Add(new 
            MediaTypeWithQualityHeaderValue(contentType));

            // List data response.
            HttpResponseMessage response = client.GetAsync(requestBody).Result;
            if (response.IsSuccessStatusCode)
            {
                // Parse the response body.
                var dataObjects = response.Content.ReadAsAsync<IEnumerable<IDataObject>>().Result;  
                //Make sure to add a reference to System.Net.Http.Formatting.dll

            }
            else
            {
                Console.WriteLine("{0} ({1})", (int)response.StatusCode, response.ReasonPhrase);
            }

            //Make any other calls using HttpClient here.

            //Dispose once all HttpClient calls are complete.
            client.Dispose();

         }
     }
 }

Answer 1

您的方法不返回任何值，因此更改签名以返回void类型：

public static void PostRestCall(string baseURL, string httpMethod, string contentType, 
string requestBody)

Answer 2

将您的方法返回类型更改为 void，或者如果您想返回任何值，请使用 return 语句。