Google 翻译API Demo

接上篇 Google翻译API(B/S调用和C/S调用)

     上篇里提到的接口调用方法是get方式，这样有个问题，每次请求翻译的内容不能超过url允许的长度。需要改成post方式才行，但是google没有提供post方式的API请求，怎么办呢？在通过网上一番资料的查找，在一位哥们的博客里看到了解决方案，不过他用的是java版的，对应post地址和参数，写出了.net版的。加上朗读的功能，程序界面如下：

        /// <summary>
        /// Post方式获取翻译
        /// </summary>
        /// <param name="sourceText"></param>
        /// <param name="langPair"></param>
        /// <returns></returns>
        private static string TranslatePostMethod(string sourceText, string langPair)
        {
            string fromLan = langPair; //原始语言
            string toLan = langPair.ToLower() == "zh" ? "en" : "zh"; //目标语言 这里只针对中英互转
            HttpWebRequest requestScore = (HttpWebRequest)WebRequest.Create("http://translate.google.com/translate_t#");
            StringBuilder postContent = new StringBuilder();
            Encoding myEncoding = Encoding.UTF8;
            postContent.Append(HttpUtility.UrlEncode("hl", myEncoding));
            postContent.Append("=");
            postContent.Append(HttpUtility.UrlEncode("en", myEncoding));
            postContent.Append("&");
            postContent.Append(HttpUtility.UrlEncode("ie", myEncoding));
            postContent.Append("=");
            postContent.Append(HttpUtility.UrlEncode("UTF-8", myEncoding));
            postContent.Append("&");
            postContent.Append(HttpUtility.UrlEncode("sl", myEncoding));
            postContent.Append("=");
            postContent.Append(HttpUtility.UrlEncode(fromLan, myEncoding));
            postContent.Append("&");
            postContent.Append(HttpUtility.UrlEncode("text", myEncoding));
            postContent.Append("=");
            postContent.Append(HttpUtility.UrlEncode(sourceText, myEncoding));
            postContent.Append("&");
            postContent.Append(HttpUtility.UrlEncode("tl", myEncoding));
            postContent.Append("=");
            postContent.Append(HttpUtility.UrlEncode(toLan, myEncoding));

            byte[] data = Encoding.ASCII.GetBytes(postContent.ToString());
            requestScore.UserAgent = "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.2; SV1; .NET CLR 1.1.4322; .NET CLR 2.0.50727)";
            requestScore.Method = "Post";
            //requestScore.ContentType = "application/x-www-form-urlencoded;charset=gb2312";
            requestScore.ContentLength = data.Length;
            requestScore.KeepAlive = true;
            requestScore.Timeout = (6 * 60 * 1000);
            requestScore.ProtocolVersion = HttpVersion.Version10;

            Stream stream = requestScore.GetRequestStream();
            stream.Write(data, 0, data.Length);
            stream.Close();
            string content = string.Empty;
            try
            {
                System.Net.ServicePointManager.Expect100Continue = false;
                HttpWebResponse responseSorce = (HttpWebResponse)requestScore.GetResponse();
                StreamReader reader = new StreamReader(responseSorce.GetResponseStream());
                content = reader.ReadToEnd();
                responseSorce.Close();
                reader.Dispose();
                stream.Dispose();
            }
            catch (WebException ex)
            {
                HttpWebResponse responseSorce = (HttpWebResponse)ex.Response;//得到请求网站的详细错误提示
                StreamReader reader = new StreamReader(responseSorce.GetResponseStream());
                content = reader.ReadToEnd();
                responseSorce.Close();
                reader.Dispose();
                stream.Dispose();
            }
            finally
            {
                requestScore.Abort();
            }
            string reg = @"<(?<HtmlTag>[\w]+)[^>]*\s[iI][dD]=(?<Quote>[""']?)result_box(?(Quote)\k<Quote>)[""']?[^>]*>((?<Nested><\k<HtmlTag>[^>]*>)|</\k<HtmlTag>>(?<-Nested>)|.*?)*</\k<HtmlTag>>"; //返回的是一个html页面，需匹配出翻译内容
            Regex r = new Regex(reg);
            MatchCollection mcItem = r.Matches(content);
            string result = ConvertHtmlToText(mcItem[0].Value);
            return "post:" + result;
        }

可执行程序下载：http://download.csdn.net/source/3499399

源代码下载：http://download.csdn.net/source/3499392

参考资料：

1.Google翻译post提交无长度限制的在线翻译例子

2.使用正则表达式匹配嵌套Html标签

3.使用正则表达式将Html转换为纯文本