/// <summary>

     /// 有道词典API

     /// </summary>

     internal class YouDaoApiService

     {

         const string AppKey = "131b76a4ee1ecd13";//AppKey和AppSecret是本人@Winter申请的账号，仅供测试使用

         const string LangEn = "en";

         const string AppSecret = "KX9hLrgSMhfKkvIqS6nhwtwMcRymJqEA";

         public static async Task<YouDaoTranslationResponse> GetTranslatioAsync(string queryText, string from = LangEn, string to = LangEn)

         {

             var requestUrl = GetRequestUrl(queryText, from, to);

             WebRequest translationWebRequest = WebRequest.Create(requestUrl);

             var response = await translationWebRequest.GetResponseAsync();

             using (Stream stream = response.GetResponseStream())

             {

                 using (StreamReader reader = new StreamReader(stream ?? throw new InvalidOperationException("有道Api查询出错！"), Encoding.GetEncoding("utf-8")))

                 {

                     string result = reader.ReadToEnd();

                     var youDaoTranslationResponse = JsonConvert.DeserializeObject<YouDaoTranslationResponse>(result);

                     return youDaoTranslationResponse;

                 }

             }

         }

         private static string GetRequestUrl(string queryText, string from, string to)

         {

             string salt = DateTime.Now.Millisecond.ToString();

             MD5 md5 = new MD5CryptoServiceProvider();

             string md5Str = AppKey + queryText + salt + AppSecret;

             byte[] output = md5.ComputeHash(Encoding.UTF8.GetBytes(md5Str));

             string sign = BitConverter.ToString(output).Replace("-", "");

             var requestUrl = string.Format(

                 "http://openapi.youdao.com/api?appKey={0}&q={1}&from={2}&to={3}&sign={4}&salt={5}",

                 AppKey,

                 HttpUtility.UrlDecode(queryText, System.Text.Encoding.GetEncoding("UTF-8")),

                 from, to, sign, salt);

             return requestUrl;

         }

     }