C#后端调用WebApi地址

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

namespace Services
{
    public class HttpHelper<T> where T : class, new()
    {
        private Uri BaseUri
        {
            get
            {
                return new Uri(GlobalString.BaseUrl);
            }
        }

        private Uri RequestUri(string requestUrl)
        {

            return new Uri(BaseUri, requestUrl);
        }

       //用Post还是用Get，要与WebApi的请求方式一致
        public async Task<T> GetPostResult(string requestUrl, FormUrlEncodedContent content)
        {
            using (var client = new HttpClient())
            {
                client.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue(GlobalString.JsonHeader));
                using (var response = await client.PostAsync(RequestUri(requestUrl), content))
                {
                    if (response.IsSuccessStatusCode)
                    {
                        var productJsonString = await response.Content.ReadAsStringAsync();
                        return JsonConvert.DeserializeObject<T>(productJsonString);
                    }
                    return new T();
                }
            }
        }
    }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Services
{
    public class GlobalString
    {
        public static string JsonHeader
        {
            get
            {
                return "application/json";
            }
        }

        public static string BaseUrl
        {
            get
            {
                return "http://www.XXX.com";
            }
        }


        public static string GetApiUrl
        {
            get
            {
                return "apiUrl";
            }
        }

    }
}