ScriptManager.AsyncPostBackError Evento

Definizione

Si verifica in presenza di un errore della pagina durante un postback asincrono.

public:
 event EventHandler<System::Web::UI::AsyncPostBackErrorEventArgs ^> ^ AsyncPostBackError;
public event EventHandler<System.Web.UI.AsyncPostBackErrorEventArgs> AsyncPostBackError;
member this.AsyncPostBackError : EventHandler<System.Web.UI.AsyncPostBackErrorEventArgs> 
Public Custom Event AsyncPostBackError As EventHandler(Of AsyncPostBackErrorEventArgs) 

Tipo evento

Esempio

Nell'esempio seguente viene illustrato come gestire l'evento AsyncPostBackError per impostare la AsyncPostBackErrorMessage proprietà (inviata al client) al messaggio di errore dell'eccezione del server.

<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    protected void ErrorProcessClick_Handler(object sender, EventArgs e)
    {
        // This handler demonstrates an error condition. In this example
        // the server error gets intercepted on the client and an alert is shown. 
        throw new ArgumentException();
    }
    protected void SuccessProcessClick_Handler(object sender, EventArgs e)
    {
        // This handler demonstrates no server side exception.
        UpdatePanelMessage.Text = "The asynchronous postback completed successfully.";
    }

    // <Snippet3>
    protected void ScriptManager1_AsyncPostBackError(object sender, AsyncPostBackErrorEventArgs e)
    {
        ScriptManager1.AsyncPostBackErrorMessage = e.Exception.Message;
    }
    // </Snippet3>

</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>PageRequestManager endRequestEventArgs Example</title>
    <style type="text/css">
    body {
        font-family: Tahoma;
    }
    #AlertDiv{
    left: 40%; top: 40%;
    position: absolute; width: 200px;
    padding: 12px; 
    border: #000000 1px solid;
    background-color: white; 
    text-align: left;
    visibility: hidden;
    z-index: 99;
    }
    #AlertButtons{
    position: absolute;
    right: 5%;
    bottom: 5%;
    }
    </style>
</head>
<body id="bodytag">
    <form id="form1" runat="server">
        <div>
            <asp:ScriptManager ID="ScriptManager1" runat="server" 
            OnAsyncPostBackError="ScriptManager1_AsyncPostBackError">
            </asp:ScriptManager>

            <script type="text/javascript" language="javascript">
                var divElem = 'AlertDiv';
                var messageElem = 'AlertMessage';
                var errorMessageAdditional = 'Please try again.';
                var bodyTag = 'bodytag';
                Sys.WebForms.PageRequestManager.getInstance().add_endRequest(EndRequestHandler);
                function ToggleAlertDiv(visString)
                {
                     if (visString == 'hidden')
                     {
                         $get(bodyTag).style.backgroundColor = 'white';                         
                     }
                     else
                     {
                         $get(bodyTag).style.backgroundColor = 'gray';                         
                        
                     }
                     var adiv = $get(divElem);
                     adiv.style.visibility = visString;
                     
                }
                function ClearErrorState() {
                     $get(messageElem).innerHTML = '';
                     ToggleAlertDiv('hidden');                     
                }
                function EndRequestHandler(sender, args)
                {
                   if (args.get_error() != undefined && args.get_error().httpStatusCode == '500')
                   {
                       var errorMessage = args.get_error().message
                       args.set_errorHandled(true);
                       ToggleAlertDiv('visible');
                       $get(messageElem).innerHTML = '"' + 
                                errorMessage + '" ' + errorMessageAdditional;
                   }
                   
                }
            </script>
            <asp:UpdatePanel runat="Server" UpdateMode="Conditional" ID="UpdatePanel1">
                <ContentTemplate>
                    <asp:Panel ID="Panel1" runat="server" GroupingText="Update Panel">
                        <asp:Label ID="UpdatePanelMessage" runat="server" />
                        <br />
                        Last update:
                        <%= DateTime.Now.ToString() %>
                        .
                        <br />
                        <asp:Button runat="server" ID="Button1" Text="Submit Successful Async Postback"
                            OnClick="SuccessProcessClick_Handler" OnClientClick="ClearErrorState()" />
                        <asp:Button runat="server" ID="Button2" Text="Submit Async Postback With Error"
                            OnClick="ErrorProcessClick_Handler" OnClientClick="ClearErrorState()" />
                        <br />
                    </asp:Panel>
                </ContentTemplate>
            </asp:UpdatePanel>
            <div id="AlertDiv">
                <div id="AlertMessage">
                </div>
                <br />
                <div id="AlertButtons" >
                    <input id="OKButton" type="button" value="OK" 
                           runat="server" onclick="ClearErrorState()" />
                </div>
           </div>
    </form>
</body>
</html>
<%@ Page Language="VB" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" 
  "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<script runat="server">

    Protected Sub ErrorProcessClick_Handler(ByVal sender As Object, ByVal e As EventArgs)
        'This handler demonstrates an error condition. In this example
        ' the server error gets intercepted on the client and an alert is shown. 
        Throw New ArgumentException()
        
    End Sub
    
    Protected Sub SuccessProcessClick_Handler(ByVal sender As Object, ByVal e As EventArgs)
        'This handler demonstrates no server side exception.
        UpdatePanelMessage.Text = "The asynchronous postback completed successfully."        
    End Sub
    
    ' <Snippet3>
    Protected Sub ScriptManager1_AsyncPostBackError(ByVal sender As Object, ByVal e As System.Web.UI.AsyncPostBackErrorEventArgs)
        ScriptManager1.AsyncPostBackErrorMessage = e.Exception.Message
    End Sub
    ' </Snippet3>

</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>PageRequestManager endRequestEventArgs Example</title>
    <style type="text/css">
    body {
        font-family: Tahoma;
    }
    #AlertDiv{
    left: 40%; top: 40%;
    position: absolute; width: 200px;
    padding: 12px; 
    border: #000000 1px solid;
    background-color: white; 
    text-align: left;
    visibility: hidden;
    z-index: 99;
    }
    #AlertButtons{
    position: absolute;
    right: 5%;
    bottom: 5%;
    }
    </style>
</head>
<body id="bodytag">
    <form id="form1" runat="server">
        <div>
            <asp:ScriptManager runat="server" ID="ScriptManager1" 
            OnAsyncPostBackError="ScriptManager1_AsyncPostBackError">
            </asp:ScriptManager>

            <script type="text/javascript" language="javascript">
                var divElem = 'AlertDiv';
                var messageElem = 'AlertMessage';
                var errorMessageAdditional = 'Please try again.';
                var bodyTag = 'bodytag';
                Sys.WebForms.PageRequestManager.getInstance().add_endRequest(EndRequestHandler);
                function ToggleAlertDiv(visString)
                {
                     if (visString == 'hidden')
                     {
                         $get(bodyTag).style.backgroundColor = 'white';                         
                     }
                     else
                     {
                         $get(bodyTag).style.backgroundColor = 'gray';                         
                        
                     }
                     var adiv = $get(divElem);
                     adiv.style.visibility = visString;
                     
                }
                function ClearErrorState() {
                     $get(messageElem).innerHTML = '';
                     ToggleAlertDiv('hidden');                     
                }
                function EndRequestHandler(sender, args)
                {
                   if (args.get_error() != undefined && args.get_error().httpStatusCode == '500')
                   {
                       var errorMessage = args.get_error().message
                       args.set_errorHandled(true);
                       ToggleAlertDiv('visible');
                       $get(messageElem).innerHTML = '"' + 
                                errorMessage + '" ' + errorMessageAdditional;
                   }
                   
                }
            </script>
            <asp:UpdatePanel runat="Server" UpdateMode="Conditional" ID="UpdatePanel1">
                <ContentTemplate>
                    <asp:Panel ID="Panel1" runat="server" GroupingText="Update Panel">
                        <asp:Label ID="UpdatePanelMessage" runat="server" />
                        <br />
                        Last update:
                        <%= DateTime.Now.ToString() %>
                        .
                        <br />
                        <asp:Button runat="server" ID="Button1" Text="Submit Successful Async Postback"
                            OnClick="SuccessProcessClick_Handler" OnClientClick="ClearErrorState()" />
                        <asp:Button runat="server" ID="Button2" Text="Submit Async Postback With Error"
                            OnClick="ErrorProcessClick_Handler" OnClientClick="ClearErrorState()" />
                        <br />
                    </asp:Panel>
                </ContentTemplate>
            </asp:UpdatePanel>
            <div id="AlertDiv">
                <div id="AlertMessage">
                </div>
                <br />
                <div id="AlertButtons" >
                    <input id="OKButton" type="button" value="OK" 
                           runat="server" onclick="ClearErrorState()" />
                </div>
           </div>
    </form>
</body>
</html>

Commenti

L'evento AsyncPostBackError viene generato quando si verifica un errore di pagina durante i postback asincroni. La modalità di invio degli errori nel server al client dipende AllowCustomErrorsRedirect dalla proprietà, dalla AsyncPostBackErrorMessage proprietà e dalla sezione errori personalizzati del file di Web.config.

Si applica a

Vedi anche