1,建幾個你需要的語言資原始檔，如圖：

2，

public class Localization3Attribute : ActionFilterAttribute
    {
        public override void OnActionExecuting(ActionExecutingContext filterContext)
        {
            var DefaultLg = string.Empty;
            var queryString = filterContext.HttpContext.Request.QueryString["lang"];
            if (queryString != null && !string.IsNullOrWhiteSpace(queryString.ToString()))
            {
                ///從路由資料(url)裡設定語言
                DefaultLg = queryString.ToString();
                Thread.CurrentThread.CurrentUICulture = CultureInfo.CreateSpecificCulture(DefaultLg);
            }
            else
            {
                //從Cookie裡面讀取語言
                var tc = filterContext.HttpContext.Request.Cookies["LG"];
                if (tc == null)
                {
                    //從Session裡讀取語言設定
                    var Sessionlang = filterContext.HttpContext.Session["LG"];
                    if (Sessionlang == null)
                    {
                        //如果Session為空，則從Cokkie裡面讀取客戶端語言首選項已排序陣列
                        DefaultLg = filterContext.HttpContext.Request.UserLanguages[0];
                        //設定預設語言
                        Thread.CurrentThread.CurrentUICulture = CultureInfo.CreateSpecificCulture(DefaultLg);
                    }
                    else
                    {
                        DefaultLg = Sessionlang.ToString();
                        Thread.CurrentThread.CurrentUICulture = CultureInfo.CreateSpecificCulture(DefaultLg);
                    }
                }
                else
                {
                    DefaultLg = tc.Value;
                    Thread.CurrentThread.CurrentUICulture = CultureInfo.CreateSpecificCulture(DefaultLg);
                }
            }
            //設定Session語言值
            filterContext.HttpContext.Session["LG"] = DefaultLg;
            //設定Cookie語言值
            HttpCookie _cookie = new HttpCookie("LG", Thread.CurrentThread.CurrentUICulture.Name);
            _cookie.Expires = DateTime.Now.AddYears(1);
            filterContext.HttpContext.Response.SetCookie(_cookie);

            base.OnActionExecuting(filterContext);
        }
    }

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