Question

我正在构建一个带有vb.net代码的asp.net网页。

我的网页旨在当用户点击按钮而不填写相关文本框时显示错误;下面的代码显示了它的工作原理：

If txtOrderNumber.Text = "" Then
        lblStatus.Text = orderNoWarning
        lblStatus.CssClass = "error"
    ElseIf txtPhaseNumber.Text = "" Then
        lblStatus.Text = phaseNoWarning
        lblStatus.CssClass = "error"
    ElseIf txtOrderNumber.Text.Length > 0 AndAlso txtPhaseNumber.Text.Length > 0 Then
        Try
            Dim intOrderNumber As Integer = CInt(txtOrderNumber.Text)
            Try
                Dim intPhaseNumber As Integer = CInt(txtPhaseNumber.Text)
                Dim objWIP_Tracking As New wsWIP_Tracking.WIP_TrackingSoapClient
                Dim myResults As wsWIP_Tracking.TicketType2 = objWIP_Tracking.GetTicketType2(intOrderNumber, intPhaseNumber)
                If myResults = wsWIP_Tracking.TicketType2.AME Or _
                   myResults = wsWIP_Tracking.TicketType2.Orion Then
                    lblStatus.Text = ""
                    Response.Redirect("http://ligrptsvr2/default.aspx?Report=JoinerySummarybyComponent.rpt&username=imservices&FOLDER=Analytics&OrderNo=" & intOrderNumber.ToString & "&PhaseNo=" & intPhaseNumber.ToString & "&ParameterPrompt=yes")
                ElseIf myResults = wsWIP_Tracking.TicketType2.GS Then
                    lblStatus.Text = ""
                    Response.Redirect("http://ligrptsvr2/default.aspx?Report=JoinerySummary_GreenScreen.rpt&username=wip&FOLDER=Analytics&JobNo=" & intOrderNumber.ToString & "&PhaseNo=" & intPhaseNumber.ToString & "&ParameterPrompt=yes")
                ElseIf myResults <> wsWIP_Tracking.TicketType2.AME Or _
                   myResults <> wsWIP_Tracking.TicketType2.Orion Or _
                   myResults = wsWIP_Tracking.TicketType2.GS Then
                    lblStatus.Text = warning
                    lblStatus.CssClass = "warning"
                Else
                    Response.End()
                End If
            Catch ex As Exception
            End Try
        Catch ex As Exception
        End Try
    Else
        lblStatus.Text = ""
    End If

但是，当response.redirect（重定向到新页面）发生时，我想清除标签（lblstatus）。代码'lblstatus.text =“”'不起作用。当用户被重定向到新页面然后返回（使用浏览器后退按钮）时，标签仍然显示错误。我试过禁用和启用viewstate;没有任何区别。我该怎么做才能清除这个标签？

Answer 1

请参阅：What happens when I press browser BACK button?

当您在浏览器中按下后退按钮时，大多数浏览器只会在重定向发生之前以最新状态显示html页面的缓存副本。该功能完全取决于浏览器。因此，您的VB代码或视图状态几乎无法执行任何操作。

一个选项是在页面加载时使用java-script来动态切换错误信息（这就是我遇到这种问题时所做的事情）。

响应重定向后的aspnet / vbnet clear标签

1 个答案: