Question

我正在尝试在类文件中提供警告消息，即.cs文件，而不是在页面的代码后面。但任何常规方法都无法实现同样的目标！

ClientScript或ScriptManager.RegisterStartupScript都要求 Control作为第一个参数，我不明白该怎么做提供！

真的有可能吗？：|如果是，那么......
有什么方法可以从类文件中提供警报？

Answer 1

在.net 1.1中工作，所以应该在更新的.net框架中工作

public class MessageBox
{
    private static Hashtable m_executingPages = new Hashtable();
    private MessageBox(){}
    /// <summary>
    /// Show Event for the Messagebox
    /// </summary>
    /// <param name="sMessage">Pass String to Display</param>
    public static void Show( string sMessage )
    {
        // If this is the first time a page has called this method then
        if( !m_executingPages.Contains( HttpContext.Current.Handler ) )
        {
            // Attempt to cast HttpHandler as a Page.
            Page executingPage = HttpContext.Current.Handler as Page;
            if( executingPage != null )
            {
                // Create a Queue to hold one or more messages.
                Queue messageQueue = new Queue();
                // Add our message to the Queue
                messageQueue.Enqueue( sMessage );
                // Add our message queue to the hash table. Use our page reference
                // (IHttpHandler) as the key.
                m_executingPages.Add( HttpContext.Current.Handler, messageQueue );
                // Wire up Unload event so that we can inject 
                // some JavaScript for the alerts.
                executingPage.Unload += new EventHandler( ExecutingPage_Unload );
            }  
        }
        else
        {
            // If were here then the method has allready been 
            // called from the executing Page.
            // We have allready created a message queue and stored a
            // reference to it in our hastable. 
            Queue queue = (Queue) m_executingPages[ HttpContext.Current.Handler ];
            // Add our message to the Queue
            queue.Enqueue( sMessage );
        }
    }

    // Our page has finished rendering so lets output the
    // JavaScript to produce the alert's
    private static void ExecutingPage_Unload(object sender, EventArgs e)
    {
        // Get our message queue from the hashtable
        Queue queue = (Queue) m_executingPages[ HttpContext.Current.Handler ];
        if( queue != null )
        {
            StringBuilder sb = new StringBuilder();
            // How many messages have been registered?
            int iMsgCount = queue.Count;
            // Use StringBuilder to build up our client slide JavaScript.
            sb.Append( "<script language='javascript'>" );
            // Loop round registered messages
            string sMsg;
            while( iMsgCount-- > 0 )
            {
                sMsg = (string) queue.Dequeue();
                sMsg = sMsg.Replace( "\n", "\\n" );
                sMsg = sMsg.Replace( "\"", "'" );
                sb.Append( @"alert( """ + sMsg + @""" );" );
            }
            // Close our JS
            sb.Append( @"</script>" );
            // Were done, so remove our page reference from the hashtable
            m_executingPages.Remove( HttpContext.Current.Handler );
            // Write the JavaScript to the end of the response stream.
            HttpContext.Current.Response.Write( sb.ToString() );
        }
    }
}

ASP.NET的类文件中的警报不在Code Behind上

1 个答案: