public class GetDataByWebApi

{

    /// <summary>

    /// 通过web api获取数据的方法

    /// </summary>

    /// <param name="url">api的url</param>

    /// <param name="method">请求类型,默认是get</param>

    /// <param name="postData">post请求所携带的数据</param>

    /// <returns></returns>

    public static string RequestData(string url, string method = "Get", string postData = null)

    {

        try

        {

            method = method.ToUpper();

            //设置安全通信协议   我方公司服务器有些强制使用tls1.2的安全通信协议,所以至少包含SecurityProtocolType.Tls12   如果沒有SecurityProtocolType.Tls12设置会报错:HttpWebRequest底层连接已关闭:传送时发生意外错误

            ServicePointManager.SecurityProtocol =

                SecurityProtocolType.Ssl3 | SecurityProtocolType.Tls |

                SecurityProtocolType.Tls11 | SecurityProtocolType.Tls12;

            //创建请求实例

            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(url);

            //设置请求类型

            request.Method = method;

            //设置请求消息主体的编码方法

            request.ContentType = "application/json";

            //POST方式處理

            if (method == "POST")

            {

                //test t = test.T;

                //t.gaga("哟西");

                //用UTF8字符集对post请求携带的数据进行编码,可防止中文乱码

                byte[] byteArray = Encoding.UTF8.GetBytes(postData);

                //指定客户端post请求携带的数据的长度

                request.ContentLength = byteArray.Length;

                //创建一个tream,用于写入post请求所携带的数据(该数据写入了请求体)

                Stream stream = request.GetRequestStream();

                stream.Write(byteArray, 0, byteArray.Length);

                stream.Close();

            }

            //获取请求的响应实例

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();

            //获取读取流实体,用来以UTF8字符集读取响应流中的数据

            StreamReader myStreamReader = new StreamReader(response.GetResponseStream(), /*Encoding.UTF8*/Encoding.Default);

            //进行数据读取

            string retString = myStreamReader.ReadToEnd();

            myStreamReader.Close();

            return retString;

        }

        catch (Exception ex)

        {

            //拋出異常

            //throw ex;

            return ex.Message;

        }

    }

}