Google Translator

• Download source - 285.8 KB

Note:
GoogleTranslator was originally written when screen scraping was the only way to access Google's online translation tools. As has been rightly pointed out in this article's forum, a more modern approach would be to use Google's AJAX APIs. See this link for more information. This screen scraper version of GoogleTranslator continues to be maintained at the request of CP readers.

This latest version of GoogleTranslator utilizes Google Translate's AJAX APIs to translate text and retrieves the translation by parsing the returned JSON content. Thanks to CPians @Member 9899010 and @bgsjust for pointing me to these APIs. The latest version of the code also includes the ability to speak the translation from the demo app. Because Google limits the speech to common words in a few languages, don't be surprised if the demo plays dumb when you try to speak your translated text!

What is it?

GoogleTranslator is an object that allows you to translate text using the power of Google's online language tools. The demo app also allows you to easily perform a reverse translation. The app can be used as a poor man's resource translator for simple phrases, but you'd be wise to confirm the translation with a native speaker before using the results.

How do I use it?

You use GoogleTranslator by constructing it and calling its Translate() method.

Hide   Copy Code

 
    using RavSoft.GoogleTranslator;
    
    Translator t = new GoogleTranslator();
    string translation = t.Translate ("Hello, how are you?", "English", "French");
    Console.WriteLine (translation);
    Console.WriteLine ("Translated in " + t.TranslationTime.TotalMilliseconds + " mSec");
    Console.WriteLine ("Translated speech = " + t.TranslationSpeechUrl);

How it works

GoogleTranslator works by directly invoking Google's translation API called by its online translation form and parsing the results.

Hide   Shrink   Copy Code

 
    // Initialize
    this.Error = null;
    this.TranslationSpeechUrl = null;
    this.TranslationTime = TimeSpan.Zero;
    DateTime tmStart = DateTime.Now;
    string translation = string.Empty;

    try {
        // Download translation
        string url = string.Format ("https://translate.google.com/translate_a/single?client=t&sl={0}" +
                                    "&tl={1}&hl=en&dt=bd&dt=ex&dt=ld&dt=md&dt=qc&dt=rw&dt=rm&dt=ss&dt=t" +
                                    "&dt=at&ie=UTF-8&oe=UTF-8&source=btn&ssel=0&tsel=0&kc=0&q={2}",
                                    Translator.LanguageEnumToIdentifier (sourceLanguage),
                                    Translator.LanguageEnumToIdentifier (targetLanguage),
                                    HttpUtility.UrlEncode (sourceText));
        string outputFile = Path.GetTempFileName();
        using (WebClient wc = new WebClient ()) {
            wc.Headers.Add ("user-agent", "Mozilla/5.0 (Windows NT 6.1) AppleWebKit/537.36 " +
                                          "(KHTML, like Gecko) Chrome/41.0.2228.0 Safari/537.36");
            wc.DownloadFile(url, outputFile);
        }

        // Get translated text
        if (File.Exists (outputFile)) {

            // Get phrase collection
            string text = File.ReadAllText(outputFile);
            int index = text.IndexOf (string.Format(",,\"{0}\"", Translator.LanguageEnumToIdentifier (sourceLanguage)));
            if (index == -1) {
                // Translation of single word
                int startQuote = text.IndexOf('\"');
                if (startQuote != -1) {
                    int endQuote = text.IndexOf('\"', startQuote + 1);
                    if (endQuote != -1) {
                        translation = text.Substring(startQuote + 1, endQuote - startQuote - 1);
                    }
                }
            }
            else {
                // Translation of phrase
                text = text.Substring(0, index);
                text = text.Replace("],[", ",");
                text = text.Replace("]", string.Empty);
                text = text.Replace("[", string.Empty);
                text = text.Replace("\",\"", "\"");
            }

            // Get translated phrases
            string[] phrases = text.Split (new[] { '\"' }, StringSplitOptions.RemoveEmptyEntries);
            for (int i=0; (i < phrases.Count()); i += 2) {
                string translatedPhrase = phrases[i];
                if (translatedPhrase.StartsWith(",,")) {
                    i--;
                    continue;
                }
                translation += translatedPhrase + "  ";
            }

            // Fix up translation
            translation = translation.Trim();
            translation = translation.Replace(" ?", "?");
            translation = translation.Replace(" !", "!");
            translation = translation.Replace(" ,", ",");
            translation = translation.Replace(" .", ".");
            translation = translation.Replace(" ;", ";");

            // And translation speech URL
            this.TranslationSpeechUrl = string.Format ("https://translate.google.com/translate_tts?ie=UTF-8"+
                                                       "&q={0}&tl={1}&total=1&idx=0&textlen={2}&client=t",
                                                       HttpUtility.UrlEncode (translation),
                                                       Translator.LanguageEnumToIdentifier (targetLanguage),
                                                       translation.Length);
        }
    }
    catch (Exception ex) {
        this.Error = ex;
    }

    // Return result
    this.TranslationTime = DateTime.Now - tmStart;
    return translation;