Proper way to change language at runtime

Question

What is the proper way to change Form language at runtime?

1. Setting all controls manually using recursion like this
2. Save language choice to file > Rest

Answer 1

I believe the solution shown in Hans Passant's comment might be the only (general) solution.

Personally, I use this base class for all forms that need to be localized:

public class LocalizedForm : Form
{
    /// 

    /// Occurs when current UI culture is changed
    /// 
    [Browsable(true)]
    [Description("Occurs when current UI culture is changed")]
    [EditorBrowsable(EditorBrowsableState.Advanced)]
    [Category("Property Changed")]
    public event EventHandler CultureChanged;

    protected CultureInfo culture;
    protected ComponentResourceManager resManager;

    /// 

    /// Current culture of this form
    /// 
    [Browsable(false)]
    [Description("Current culture of this form")]
    [EditorBrowsable(EditorBrowsableState.Never)]
    public CultureInfo Culture
    {
        get { return this.culture; }
        set
        {
            if (this.culture != value)
            {
                this.ApplyResources(this, value);

                this.culture = value;
                this.OnCultureChanged();
            }
        }
    }

    public LocalizedForm()
    {
        this.resManager = new ComponentResourceManager(this.GetType());
        this.culture = CultureInfo.CurrentUICulture;
    }

    private void ApplyResources(Control parent, CultureInfo culture)
    {
        this.resManager.ApplyResources(parent, parent.Name, culture);

        foreach (Control ctl in parent.Controls)
        {
            this.ApplyResources(ctl, culture);
        }
    }

    protected void OnCultureChanged()
    {
        var temp = this.CultureChanged;
        if (temp != null)
            temp(this, EventArgs.Empty);
    }
}

Then instead of directly changing Thread.CurrentThread.CurrentUICulture, I use this property in static manager class to change UI culture:

public static CultureInfo GlobalUICulture
{
    get { return Thread.CurrentThread.CurrentUICulture; }
    set
    {
        if (GlobalUICulture.Equals(value) == false)
        {
            foreach (var form in Application.OpenForms.OfType())
            {
                form.Culture = value;
            }

            Thread.CurrentThread.CurrentUICulture = value;
        }
    }
}