h5调用第三方api时候经常遇到不允许跨域的问题，用webapi实现一个代理http接口，方便进行跨域请求。

using Newtonsoft.Json;
using Newtonsoft.Json.Linq;
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.Web.Http;
using YFAPICommon.Models;

namespace YFAPICommon.Controllers
{
public class HttpInput
{
public string url { set; get; }
public Dictionary param { set; get; }
}
public class HttpProxyController : ApiController
{
public object doPost(HttpInput input)
{
if (string.IsNullOrWhiteSpace(input.url))
return ReturnNode.ReturnError(“url不能为空”);
if (input.param == null)
input.param = new Dictionary();
string result = Post(input.url,input.param);
if (result != null)
{
try
{
JObject obj = JsonConvert.DeserializeObject(result);
return obj;
}
catch (Exception ex)
{
}
}
return result;
}

    public object doGet(HttpInput input){if (string.IsNullOrWhiteSpace(input.url))return ReturnNode.ReturnError("url不能为空");if (input.param == null)input.param = new Dictionary();string result = Get(input.url);if (result != null){try{JObject obj = JsonConvert.DeserializeObject(result);return obj;}catch (Exception ex){}}return result;}private static string Post(string url, Dictionary param){using (HttpClient client = new HttpClient()){//请求超时//client.Timeout = new TimeSpan(5000);var httpContent = new StringContent(JsonConvert.SerializeObject(param));httpContent.Headers.ContentType = new MediaTypeHeaderValue("application/json");var response = client.PostAsync(url, httpContent).Result;var responseValue = response.Content.ReadAsStringAsync().Result;if (response.StatusCode == System.Net.HttpStatusCode.OK){return responseValue;}return null;}}private static string Get(string url){var request = (HttpWebRequest)WebRequest.Create(url);var response = (HttpWebResponse)request.GetResponse();var responseString = new StreamReader(response.GetResponseStream()).ReadToEnd();if (response.StatusCode == System.Net.HttpStatusCode.OK){return responseString;}return null;}
}

}