客户端多语技术

定义一个类继承自IhttpModule,在Init方法中注册preRequestHandlerExecute事件，
通过实例化HttpApplication获取http请求内容，然后根据这些请求内容
从资源文件中取得客户端提示，
并且以js变量串的形式输出到当前页面

 

/ <summary>
/// ClientTipMultiLanguageHandler 的摘要说明
/// </summary>
public class ClientTipHandler : IHttpModule
{
    public void Init(HttpApplication app)
    {
        app.PreRequestHandlerExecute += new EventHandler(PreRequestHandlerExecuteHandler);
    }
  
    void PreRequestHandlerExecuteHandler(object sender, EventArgs e)
    {
        HttpApplication app = (HttpApplication)sender;
        HttpContext currentContext = app.Context;
        IHttpHandler currentHandler=app.Context.Handler;
        if (currentHandler != null && currentHandler is Page)
        {
            Page currentPage = (Page)currentHandler;
            //从当前线程中获取使用的语言
            string lang = Thread.CurrentThread.CurrentUICulture.Name; //ConfigurationManager.AppSettings["lang"];
            string currentURL = currentContext.Request.Url.ToString();
            //当前请求的页的名字，不包含后缀
            string currentPageName = null;
            if (currentURL != null)
            {
                string[] temp = currentURL.Split('/');
                //当前请求页的名字，不包括后缀，如为InventoryEdit
                currentPageName = temp[temp.Length - 1].Split('.')[0];
            }

            #region 向业务模块的页面中输出自己页面所需要的js变量(也就是客户端提示语)

            //由当前请求的URL来获取当前页所属模块对应的资源文件的名字，不包含后缀和文化信息，如当文件名为"AA.en-US.resx"时，此处得到的是"AA"
            string resFileName = GetResouceFileNameOfModule(HttpContext.Current.Request.AppRelativeCurrentExecutionFilePath);
            string cacheKey =resFileName+"."+lang+"."+currentPageName;
            //如果缓存为空，则从资源文件中取得客户端提示，并且以js变量串的形式输出到当前页面,且缓存起来。
            object cachedContent = currentContext.Cache[cacheKey];
            if (cachedContent == null)
            {
                #region

                #region 获取当前模块对应的资源文件的路径和名称

                string directory = GetResourceDirectory();              
                string fileName = HttpContext.Current.Server.MapPath(@"~/" + directory + "//" + resFileName + "." + lang + ".resx");
                if (!File.Exists(fileName))
                {
                    fileName = HttpContext.Current.Server.MapPath(@"~/" + directory + "//" + resFileName + ".resx");
                    if (!File.Exists(fileName))
                    {
                        return;
                    }
                }
                #endregion
                #region 按规则读取资源文件中的条目，并以javascript变量的形式输出到页面中
                string key = null;
                string value = null;
                StringBuilder clientTipsVars = new StringBuilder();
                ResXResourceReader reader = new ResXResourceReader(fileName);
                IDictionaryEnumerator id = reader.GetEnumerator();
                clientTipsVars.Append("<script type=/"text/javascript/">" + "/n");
                foreach (DictionaryEntry entry in reader)
                {
                    key = entry.Key.ToString();
                    //当是模块的客户端提示的公共变量时（当前模块的所有页都可以用的JS变量）提取出来
                    //或为当前页需要的变量时，提取出来　
                    //由于用户输入的URL不区分大小写，所以把currentPageName转换为小写，key也转换为小写，来比较
                    if (key.StartsWith("ClientTip_Common_")||key.ToLower().StartsWith("clienttip_"+currentPageName.ToLower()+"_"))
                    {
                        value = entry.Value.ToString();
                        clientTipsVars.Append("var " + key + " = /"" + value + "/";" + "/n");
                    }
                   
                }
                clientTipsVars.Append("</script>/n");
                #endregion
                currentContext.Cache.Add(cacheKey, clientTipsVars.ToString(), null, DateTime.Now.AddHours(24), Cache.NoSlidingExpiration, CacheItemPriority.Normal, null);
                currentPage.RegisterStartupScript("ClientTip", clientTipsVars.ToString());
                #endregion
            }
            else
            {               
                currentPage.RegisterStartupScript("ClientTip", cachedContent.ToString());
            }
            #endregion

            #region 向业务模块的页面中输出公共的js变量（也就是客户端提示语）

            string relativeURL = HttpContext.Current.Request.AppRelativeCurrentExecutionFilePath;           
            string isBizPage = GetResouceFileNameOfModule(relativeURL);
            //如果当前请求的页面是业务做的页面（而不是平台做的页面），则向页面中输出公共提示
            if (isBizPage != "IsNotBizPage")
            {
                string uaCachKey = "UA_Common_ClientTip."+lang;
                //如果缓存中没有，则产生，并加入到缓存中
                if (HttpContext.Current.Cache[uaCachKey] == null)
                {
                    #region

                    #region 获取"UA"资源文件的路径和名称
                    string resDirctory = GetResourceDirectory();
                    string uaFileName = HttpContext.Current.Server.MapPath(@"~/" + resDirctory + "//" + "UA" + "." + lang + ".resx");
                    if (!File.Exists(uaFileName))
                    {
                        uaFileName = HttpContext.Current.Server.MapPath(@"~/" + resDirctory + "//" + "UA" + ".resx");
                        if (!File.Exists(uaFileName))
                        {
                            return;
                        }
                    }
                    #endregion
                    #region 按规则读取UA资源文件中的条目，并以javascript变量的形式输出到页面中
                    string key = null;
                    string value = null;
                    StringBuilder clientTipsVars = new StringBuilder();
                    ResXResourceReader reader = new ResXResourceReader(uaFileName);
                    IDictionaryEnumerator id = reader.GetEnumerator();
                    clientTipsVars.Append("<script type=/"text/javascript/">" + "/n");
                    foreach (DictionaryEntry entry in reader)
                    {
                        key = entry.Key.ToString();
                        //UA中的以“UA_Common_ClientTip_”开头的串输出到页面
                        if (key.StartsWith("UA_Common_ClientTip_"))
                        {
                            value = entry.Value.ToString();
                            clientTipsVars.Append("var " + key + " = /"" + value + "/";" + "/n");
                        }

                    }
                    clientTipsVars.Append("</script>/n");
                    #endregion

                    currentContext.Cache.Add(uaCachKey, clientTipsVars.ToString(), null, DateTime.Now.AddHours(24), Cache.NoSlidingExpiration, CacheItemPriority.Normal, null);
                    currentPage.RegisterStartupScript("ClientTip_Common", clientTipsVars.ToString());
                    #endregion
                }
                else
                {
                    currentPage.RegisterStartupScript("ClientTip_Common", HttpContext.Current.Cache[uaCachKey].ToString());
                }
            }

            #endregion

        }
    }

    public void Dispose()
    {

    }
    //获取资源文件所在目录
    string GetResourceDirectory()
    {
        string directory = "";

        if (ConfigurationManager.AppSettings["released"] == null)
        {
            directory = "App_GlobalResources";
        }
        else
        {
            if (ConfigurationManager.AppSettings["released"].ToLower() == "true")
            {
                directory = "ClientTipResources";
            }
            else
            {
                directory = "App_GlobalResources";
            }

        }
        return directory;

    }

    //根据模块页面的基路径，获取它对应的资源文件的名字，如果不是业务模块的页面（而是平台的），则返回串“IsNotBizPage”
    string GetResouceFileNameOfModule(string relativeURL)
    {

        SortedList<string, string> moduleURLBaseNameAndResourceNamePairs = new SortedList<string, string>();
        moduleURLBaseNameAndResourceNamePairs.Add("BaseInfo", "AA");
        moduleURLBaseNameAndResourceNamePairs.Add("SA", "SA");
        moduleURLBaseNameAndResourceNamePairs.Add("CS", "CS");
        moduleURLBaseNameAndResourceNamePairs.Add("ARAP", "ARAP");
        moduleURLBaseNameAndResourceNamePairs.Add("Stock", "ST");
        moduleURLBaseNameAndResourceNamePairs.Add("UA", "UA");
        moduleURLBaseNameAndResourceNamePairs.Add("CommonPage", "UA");
        moduleURLBaseNameAndResourceNamePairs.Add("Purchase", "PU");
        moduleURLBaseNameAndResourceNamePairs.Add("RT", "UA");
        foreach (string key in moduleURLBaseNameAndResourceNamePairs.Keys)
        {
            string relativeURLUpperCase=relativeURL.ToUpper();
            string moduleURLBaseUpperCase = key.ToUpper();
            //由于用户输入的URL不区分大小写，所以统一转换为大写
            if (relativeURLUpperCase.StartsWith("~/" + moduleURLBaseUpperCase + "/"))
            {
                return moduleURLBaseNameAndResourceNamePairs[key];
            }
        }
        return "IsNotBizPage";
       
    }
}