为什么语言不会在回发时发生变化？

Question

My dropdownlist has a list of languages with values in the form of en-NZ, en-US etc but the page doesn't change the language on postback is my language codes wrong. Could someone have a look at my code and tell me what I'm doing wrong to change the language for my page

And my lbllanguage.Text changes on the second postback aswell so it's suppose to change on the ChangeLanguage_Click event first time it is clicked

Main Page:

protected void Page_PreRender(object sender, EventArgs e)
{
    string Culture = (HttpContext.Current.Profile as ProfileCommon).Preferences.Culture;
    if (ddlChangeLanguage.Items.FindByValue(Culture) != null)
    {
        ddlChangeLanguage.SelectedValue = (HttpContext.Current.Profile as ProfileCommon).Preferences.Culture; 
    }
}

protected void Page_Load(object sender, EventArgs e)
{
    if (!Page.IsPostBack)
    {
        List<CultureInfo> languages = CultureInfo.GetCultures(CultureTypes.SpecificCultures).OrderBy(x => x.Name).ToList();

        SortedDictionary<string, string> sortedLanguages = new SortedDictionary<string, string>();

        foreach (CultureInfo language in languages)
        {
            RegionInfo regionInfo = new RegionInfo(language.Name);
            if (!sortedLanguages.ContainsKey(regionInfo.EnglishName))
            {
                sortedLanguages.Add(regionInfo.EnglishName, language.Name);
            }
        }

        foreach (KeyValuePair<string, string> language in sortedLanguages)
        {
            ddlChangeLanguage.Items.Add(new ListItem { Value = language.Value, Text = language.Key });
        }
        ddlChangeLanguage.SelectedValue = (HttpContext.Current.Profile as ProfileCommon).Preferences.Culture;
    }
    lbllanguage.Text = this.UICulture;

}

protected void ChangeLanguage_Click(object sender, EventArgs e)
{
    (HttpContext.Current.Profile as ProfileCommon).Preferences.Culture = ddlChangeLanguage.SelectedValue;
}

and my BasePage which my main page inherits

public class BasePage : System.Web.UI.Page
{
    public BasePage()
    {
    }

    protected override void InitializeCulture()
    {            
        this.Culture = (HttpContext.Current.Profile as ProfileCommon).Preferences.Culture;
        this.UICulture = (HttpContext.Current.Profile as ProfileCommon).Preferences.Culture;
    }
}

Answer 1

You have to store your strings in a resource file or satellite assemblies for translations to happen:

ASP.NET Web Page Resources Overview

<asp:Button ID="Button1" runat="server" 
    Text="<%$ Resources:WebResources, Button1Caption %>" />

Answer 2

Configure the current thread too:

var culture = (HttpContext.Current.Profile as ProfileCommon).Preferences.Culture;
Thread.CurrentThread.CurrentCulture = culture;
Thread.CurrentThread.CurrentUICulture = culture;

Answer 3

尝试将Page_PreRender中的逻辑更改为DropDownList.SelectedIndexChanged的处理程序。