ASP.NET模拟http进行GET/POST请求

备忘录：C#请求外部接口的两种POST方式。

1. 通过FormBody参数形式请求：

        /// 发送请求  
        /// </summary>  
        /// <param name="url">请求地址</param>  
        /// <param name="sendData">参数格式 “name=张三&pass=123456”</param>  
        /// <returns></returns>  
        public static string RequestWebAPI(string url, string sendData)
        {
            string backMsg = "";
            try
            {
                System.Net.WebRequest httpRquest = System.Net.HttpWebRequest.Create(url);
                httpRquest.Method = "POST";
                //这行代码很关键，不设置ContentType将导致后台参数获取不到值  
                httpRquest.ContentType = "application/x-www-form-urlencoded;charset=UTF-8";
                byte[] dataArray = System.Text.Encoding.UTF8.GetBytes(sendData);
                //httpRquest.ContentLength = dataArray.Length;  
                System.IO.Stream requestStream = null;
                if (string.IsNullOrWhiteSpace(sendData) == false)
                {
                    requestStream = httpRquest.GetRequestStream();
                    requestStream.Write(dataArray, 0, dataArray.Length);
                    requestStream.Close();
                }
                System.Net.WebResponse response = httpRquest.GetResponse();
                System.IO.Stream responseStream = response.GetResponseStream();
                System.IO.StreamReader reader = new System.IO.StreamReader(responseStream, System.Text.Encoding.UTF8);
                backMsg = reader.ReadToEnd();

                reader.Close();
                reader.Dispose();

                requestStream.Dispose();
                responseStream.Close();
                responseStream.Dispose();
            }
            catch (Exception)
            {
                throw;
            }
            return backMsg;
        }  

2. 通过json参数形式请求：

    public string GetPage(string posturl, string postData)
    {
        Stream outstream = null;
        Stream instream = null;
        StreamReader sr = null;
        HttpWebResponse response = null;
        HttpWebRequest request = null;
        Encoding encoding = Encoding.UTF8;
        byte[] data = encoding.GetBytes(postData);
        try
        {
            // 设置参数
            request = WebRequest.Create(posturl) as HttpWebRequest;
            CookieContainer cookieContainer = new CookieContainer();
            request.CookieContainer = cookieContainer;
            request.AllowAutoRedirect = true;
            request.Method = "POST";
            request.ContentType = "application/json";
            request.ContentLength = data.Length;
            outstream = request.GetRequestStream();
            outstream.Write(data, 0, data.Length);
            outstream.Close();
            //发送请求并获取相应回应数据
            response = request.GetResponse() as HttpWebResponse;
            //直到request.GetResponse()程序才开始向目标网页发送Post请求
            instream = response.GetResponseStream();
            sr = new StreamReader(instream, encoding);
            //返回结果网页（html）代码
            string content = sr.ReadToEnd();
            string err = string.Empty;
            //   Response.Write(content);
            return content;
        }
        catch (Exception ex)
        {
            string err = ex.Message;
            return string.Empty;
        }
    }