利用谷歌网站的翻译网站，实现谷歌翻译api

代码是之前网上找到的，地址为：http://www.crifan.com/teach_you_how_to_find_free_google_translate_api/

原先的代码有不足，如果翻译里包含两个句子，google会返回多句，代码只能获得第一句的翻译，所以这里做了一定的修改。

因为这个api是利用google自己网站的api，说不定哪天更新了就不能用了，所以要用趁早。

        static public string TranslateGoogleString(string strToTranslate, string fromLanguage, string toLanguage)
        {
            string translatedStr = "";
            string transRetHtml = "";

            string encodedStr = HttpUtility.UrlEncode(strToTranslate);
            string googleTransBaseUrl = "http://translate.google.cn/translate_a/t?";
            string googleTransUrl = googleTransBaseUrl;
            googleTransUrl += "&client=" + "t";
            googleTransUrl += "&text=" + encodedStr;
            googleTransUrl += "&hl=" + "zh-CN";
            googleTransUrl += "&sl=" + fromLanguage;// source   language
            googleTransUrl += "&tl=" + toLanguage;  // to       language
            googleTransUrl += "&ie=" + "UTF-8";     // input    encode
            googleTransUrl += "&oe=" + "UTF-8";     // output   encode

            try
            {
                var bytes = new WebClient().DownloadData(googleTransUrl);
                transRetHtml = Encoding.UTF8.GetString(bytes);

                var index = transRetHtml.IndexOf("]],");
                transRetHtml = transRetHtml.Substring(0, index+1).Replace("[[", "");
                
                foreach (Match m in new Regex(@"\[""(.+?)"","".+?"","".+?"",""\w*""\]").Matches(transRetHtml))
                {
                    var s = m.Value.TrimEnd(']') + ",";
                    var g2 = new Regex(@"""(.+?)"",").Match(s).Groups;
                    if (g2.Count >= 2)
                    {
                        translatedStr += g2[1].Value;
                    }
                }

            }
            catch(Exception ex)
            {
                Console.WriteLine(ex);
            }

            return translatedStr;
        }