Multilanguage applications with C# with database support

[5/3/2012: I updated this post with a new version of this library for WPF, keeping this post separated because for Winforms this library is still okay. Check it here]

Download the sample application: https://mesta-automation.com/Downloads/changeLanguage.rar

As i wrote in an earlier post, the best way to realize a multilanguage application is to get translated text from a database.

I think that one of the best database to use for translations is MS Access, because every translator has an office suite installed on his PC, and for him makes no difference translate on Excel or Access, but if you ask him to translate your sentences on “a random SQL data viewer”, it can be a pain.

To support multilanguage in my apps i use a method that, given the name of control, returns a string containing the translated text, like:

lblSample.Content = Translation.GetString("lblSample");

The reference to the culture is contained inside Settings, and that’s where i modify my language preferences, so when i load the program i know automatically what language i should use.

To realize a multilanguage selection you need:

– a listbox containing the list of languages,

– an “Apply” button

Features:

– The listbox should automatically detect the new languages

– The application should change not only the texts, but also date/time format, right to left writing and so on.

1#: Create a database file with access like in the sample and add it to the project:

2#: Download the translation class from

here

and paste it in your project,

or you can download the class with the working sample here:

https://mesta-automation.com/Downloads/changeLanguage.rar

3#: Add the current culture field on “Settings”: this field will be used on all the project to set the national preferences.

4#: Customize the translation class modifying the namespace and the table rererences, if you modified them.

using ChangeLanguage.Properties; // modify the namespace with your project name
[...]
//connection string
 private static DatabaseResourceManager databaseResourceManager = new DatabaseResourceManager(settings.translationsConnectionString);

[...]
OleDbCommand command = new OleDbCommand("Select * From Translations"); // Here there is the reference to table name
[...]
command.CommandText = "SELECT [key], [" + language + "] " + "FROM Translations"; // Here there is the reference to table name

5#: Create the GUI like in the example:

if you use xaml you can use this code:

 <label></label>
 <button name="btnApply"></button>
 <button name="btnButton"></button>
 <label></label>
 <label></label>
 <label></label>

6# Then in the main window you can write methods to fill the language comboBox

///
<summary> Detects languages in database and fill the listbox </summary>
private void LoadCmbItems()
{
    try
    {
        List cultureList = Translations.GetCultureList();
        listLanguages.ItemsSource = cultureList;
        listLanguages.SelectedItem = settings.currentCulture;
        Date = DateTime.Now;
    }
    catch (Exception exc)
    {
        MessageBox.Show(exc.Message, "Language Database error", MessageBoxButton.OK, MessageBoxImage.Error);
    }
}

and to load / change texts (but usually i do this only on the launch of application)

private void SetTextsInCurrentLanguage()
{
    this.Language = XmlLanguage.GetLanguage(CultureInfo.CurrentCulture.IetfLanguageTag);
    LoadCmbItems();
    lblLanguages.Content = Translations.GetString("lblLanguages");
    btnApply.Content = Translations.GetString("btnApply");
    btnButton.Content = Translations.GetString("btnButton");
    lblLabel.Content = Translations.GetString("lblLabel");
    lblDateTime.Content = Translations.GetString("lblDateTime");
}

You can see that it’s really simple to extract translation with this method, it’s just needed that you pass the name of the control to the method GetString to receice the translated Content.
7#: Once you wrote all translations, you can update the constructor of the main window to load the localized language and settings:

public MainWindow()
{
    Thread.CurrentThread.CurrentCulture = settings.currentCulture;
    Thread.CurrentThread.CurrentUICulture = settings.currentCulture;
    this.DataContext = this;
    InitializeComponent();
    SetTextsInCurrentLanguage();
}

and also create the button “Apply”, that basically changes the settings (and in the example refresh the GUI also) :

private void btnApply_Click(object sender, RoutedEventArgs e)
{
    settings.currentCulture = (CultureInfo)listLanguages.SelectedItem;
    Thread.CurrentThread.CurrentCulture = settings.currentCulture;  //not so good to see... just to explain how it works
    Thread.CurrentThread.CurrentUICulture = settings.currentCulture;//you should force the user to re-initialize the program
    SetTextsInCurrentLanguage();
}

You can download the full example here:

https://mesta-automation.com/Downloads/changeLanguage.rar

and read the full documentation here:

http://en.csharp-online.net/Localization_Like_the_Pros 

Disclaimer

The sample code described herein is provided on an “as is” basis, without warranty of any kind, to the fullest extent permitted by law.