如何处理“超出最大长度”错误好不好？

Question

当我尝试上传 9MB 大小的文档时，遇到“超出最大长度”错误。我知道如果 web.config 中的 httpRuntime maxRequestLength 和 requestLengthDiskThreshold 增加，问题就会得到解决，但我正在寻找的是如何能够很好地处理错误并向用户显示消息。我确实尝试在全局 ascx 中使用 Application_Error 事件，但该事件未触发。原因可能来自于 DNN PageBase 类的 OnError 方法中的 Server.Transfer。
规格：

• NET 3.5 SP1 (ASP.NET)
• IIS 6
• DotNetNuke 5.4.4(2)

非常紧急，非常感谢您的建议。 谢谢

Answer 1

几个月前我遇到了类似的问题，这篇文章非常有帮助： http://www.velocityreviews.com/forums/showpost.php?p=3794467&postcount=8

基本上，您将代码添加到 global.asax 代码隐藏中以嗅探每个页面请求。如果附加了文件，它会在上传到实际页面之前检查文件大小。工作起来就像冠军一样。

我在 VB 中需要它，所以以防万一你也这样做......我会为你保存转换；）

Sub Application_BeginRequest(ByVal sender As Object, ByVal e As EventArgs)

    Dim runtime As System.Web.Configuration.HttpRuntimeSection = System.Web.Configuration.WebConfigurationManager.GetSection("system.web/httpRuntime")
    Dim maxRequestLength As Integer = (runtime.MaxRequestLength - 100) * 1024

    Dim context As HttpContext = CType(sender, HttpApplication).Context

    If context.Request.ContentLength > maxRequestLength Then
        Dim pro As IServiceProvider = CType(context, IServiceProvider)
        Dim workerRequest As HttpWorkerRequest = DirectCast(pro.GetService(GetType(HttpWorkerRequest)), HttpWorkerRequest)

        If workerRequest.HasEntityBody Then
            Dim requestLength As Integer = workerRequest.GetTotalEntityBodyLength

            Dim initialBytes As Integer = 0

            If workerRequest.GetPreloadedEntityBody IsNot Nothing Then initialBytes = workerRequest.GetPreloadedEntityBody.Length

            If Not workerRequest.IsEntireEntityBodyIsPreloaded Then
                Dim buffer As Byte() = New Byte(511999) {}
                Dim receivedBytes As Integer = initialBytes

                While (requestLength - receivedBytes) >= initialBytes
                    initialBytes = workerRequest.ReadEntityBody(buffer, buffer.Length)
                    receivedBytes += initialBytes

                End While
                initialBytes = workerRequest.ReadEntityBody(buffer, requestLength - receivedBytes)
            End If

            Response.Redirect("~/errorPages/MaxLength.htm")

        End If
    End If



End Sub