Google翻譯V2不能包含來自C＃的大文本翻譯

Question

我已經使用Google翻譯V2 API與GET方法實現了C＃代碼。 它成功地翻譯了小文本，但是當增加文本長度並且需要1800個字符（包括URI參數）時，我得到了「URI太大」的錯誤。

好吧，我燒掉了所有的路徑，並調查了在互聯網上發佈的多個頁面的問題。他們都清楚地說GET方法應該被覆蓋以模擬POST方法（它旨在提供對5,000個字符的URI的支持），但是沒有辦法找到它的代碼示例。

有沒有人有任何例子或可以提供一些信息？

[編輯]這是我使用的代碼：

String apiUrl = "https://www.googleapis.com/language/translate/v2?key={0}&source={1}&target={2}&q={3}"; 
      String url = String.Format(apiUrl, Constants.apiKey, sourceLanguage, targetLanguage, text); 
      Stream outputStream = null; 

     byte[] bytes = Encoding.ASCII.GetBytes(url); 

     // create the http web request 
     HttpWebRequest webRequest = (HttpWebRequest)WebRequest.Create(url); 
     webRequest.KeepAlive = true; 
     webRequest.Method = "POST"; 
     // Overrride the GET method as documented on Google's docu. 
     webRequest.Headers.Add("X-HTTP-Method-Override: GET"); 
     webRequest.ContentType = "application/x-www-form-urlencoded"; 

     // send POST 
     try 
     { 
      webRequest.ContentLength = bytes.Length; 
      outputStream = webRequest.GetRequestStream(); 
      outputStream.Write(bytes, 0, bytes.Length); 
      outputStream.Close(); 
     } 
     catch (HttpException e) 
     { 
      /*...*/ 
     } 

     try 
     { 
      // get the response 
      HttpWebResponse webResponse = (HttpWebResponse)webRequest.GetResponse(); 
      if (webResponse.StatusCode == HttpStatusCode.OK && webRequest != null) 
      { 
       // read response stream 
       using (StreamReader sr = new StreamReader(webResponse.GetResponseStream(), Encoding.UTF8)) 
       { 
        string lista = sr.ReadToEnd(); 

        DataContractJsonSerializer serializer = new DataContractJsonSerializer(typeof(TranslationRootObject)); 
        MemoryStream stream = new MemoryStream(Encoding.UTF8.GetBytes(lista)); 
        TranslationRootObject tRootObject = (TranslationRootObject)serializer.ReadObject(stream); 
        string previousTranslation = string.Empty; 

        //deserialize 
        for (int i = 0; i < tRootObject.Data.Detections.Count; i++) 
        { 
         string translatedText = tRootObject.Data.Detections[i].TranslatedText.ToString(); 
         if (i == 0) 
         { 
          text = translatedText; 
         } 
         else 
         { 
          if (!text.Contains(translatedText)) 
          { 
           text = text + " " + translatedText; 
          } 
         } 
        } 
        return text; 
       } 
      } 
     } 
     catch (HttpException e) 
     { 
      /*...*/ 
     } 

     return text; 
    } 

Answer 1

顯然使用WebClient根據需要將無法正常工作，因爲你不能改變標題，per the documentation：

Note: You can also use POST to invoke the API if you want to send more data in a single request. The q parameter in the POST body must be less than 5K characters. To use POST, you must use the X-HTTP-Method-Override header to tell the Translate API to treat the request as a GET (use X-HTTP-Method-Override: GET).

您可以使用WebRequest，但你需要添加X-HTTP-Method-Override頭：

var request = WebRequest.Create (uri); 
request.Method = "POST"; 
request.ContentType = "application/x-www-form-urlencoded"; 
request.Headers.Add("X-HTTP-Method-Override", "GET"); 

var body = new StringBuilder(); 
body.Append("key=SECRET"); 
body.AppendFormat("&source={0}", HttpUtility.UrlEncode(source)); 
body.AppendFormat("&target={0}", HttpUtility.UrlEncode(target)); 
//-- 
body.AppendFormat("&q={0}", HttpUtility.UrlEncode(text)); 

var bytes = Encoding.ASCII.GetBytes(body.ToString()); 
if (bytes.Length > 5120) throw new ArgumentOutOfRangeException("text"); 

request.ContentLength = bytes.Length; 
using (var output = request.GetRequestStream()) 
{ 
    output.Write(bytes, 0, bytes.Length); 
} 

Answer 2

？什麼？使用C＃發佈是微不足道的 - 它就在文檔中。

HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri); 
{ 
    // Set type to POST 
    request.Method = "POST"; 

從那裏你基本上把數據放到fom字段到內容流中。

這不是「模擬帖子的方法」，它完全按照規範做了一個帖子請求。

Btw。 JSON在哪裏進入？你說「用C＃」。沒有必要使用json？

Answer 3

接受的答案似乎已過時。您現在可以成功使用WebClient（.net 4.5）到POST，以確保設置X-HTTP-Method-Override標題的谷歌翻譯API。

這是一些代碼，告訴你如何。

using (var webClient = new WebClient()) 
{ 
    webClient.Headers.Add("X-HTTP-Method-Override", "GET"); 
    var data = new NameValueCollection() 
    { 
     { "key", GoogleTranslateApiKey }, 
     { "source", "en" }, 
     { "target", "fr"}, 
     { "q", "<p>Hello World</p>" } 
    }; 
    try 
    { 
     var responseBytes = webClient.UploadValues(GoogleTranslateApiUrl, "POST", data); 
     var json = Encoding.UTF8.GetString(responseBytes); 
     var result = JsonConvert.DeserializeObject<dynamic>(json); 
     var translation = result.data.translations[0].translatedText; 
    } 
    catch (Exception ex) 
    { 
     loggingService.Error(ex.Message); 
    } 
}