错误处理

转载 于 2008-10-09 21:33:00 发布 · 511 阅读 · 0
文章标签：

#server #button #javascript #asp #c#

本文演示了如何在ASP.NET AJAX中处理异步回传时发生的错误。通过客户端JavaScript和服务器端C#代码相结合的方式，实现了异常捕获及友好的错误提示。

在页面回传时如果发生了异常AsyncPostBackError事件将被触发，错误信息的处理依赖于AllowCustomErrors属性、AsyncPostBackErrorMessage属性和Web.config中的<customErrors>配置区。下面看一个简单的错误处理例子，在AsyncPostBackError事件中捕获到异常信息并设置AsyncPostBackErrorMessage属性。

<%@ Page Language="C#" %>

<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.";

    }

    protected void ScriptManager1_AsyncPostBackError(object sender, AsyncPostBackErrorEventArgs e)

    {
        ScriptManager1.AsyncPostBackErrorMessage = "异常信息为：" + e.Exception.Message;

    }

</script>


<html xmlns="http://www.w3.org/1999/xhtml">

<head id="Head1" 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>

运行后时界面：

发生异常信息：

评论
成就一亿技术人!
拼手气红包6.0元
还能输入1000个字符
 
红包 添加红包
表情包 插入表情
表情包 代码片
 条评论被折叠 查看
添加红包

请填写红包祝福语或标题

个

红包个数最小为10个

元

红包金额最低5元

当前余额3.43元 前往充值 >
需支付：10.00元
成就一亿技术人!
领取后你会自动成为博主和红包主的粉丝 规则
hope_wisdom
发出的红包
实付元
使用余额支付
点击重新获取
扫码支付
钱包余额 0

抵扣说明：

1.余额是钱包充值的虚拟货币，按照1:1的比例进行支付金额的抵扣。
2.余额无法直接购买下载，可以购买VIP、付费专栏及课程。

余额充值