Question

我使用ASP.NET 4.0路由并从数据库中读取路由信息并添加如下路由。简而言之，我的自定义对象＆＃34; RouteLookup＆＃34;包含路由信息，包括可能重定向或不重定向到的另一个RouteLookup的ID。这是db中两个RouteLookup条目的示例：

    RouteLookupID   RouteName       RelativePath    RequestHandler  RouteHandler    IsSecure    RedirectedToRoute
    13              PrivacyRoute    about/privacy   privacy.aspx    NULL               0             0
    14              PrivacyRoute1   privacy         privacy.aspx    NULL               0             13

RouteLookupID 14是一个需要永久重定向到RouteLookupID 13的传统路由。我遇到的问题是我请求＆＃34; http://mydomain.com/privacy＆＃34;从浏览器和观看Fiddler结果，它实际上重定向TWICE并添加＆＃34; count = 0＆＃34;作为查询字符串参数！我没有IDEA这个参数的来源，因为我没有明确添加的进程，httphandler等。

这里到底发生了什么？任何想法都非常感谢，其余的相关代码如下。

我有一个继承自Route的类BaseRoute，所以我可以传递我的自定义RouteLookup对象，以便在我自己命名为BaseRouteHandler的自定义RouteHandler中进行检查。

Public Class PageRouter

Private Shared db As New QADBDataContext

''''''' Is called from Global Application_Start
Public Shared Sub MapRoutes(routeColl As RouteCollection)

    Dim routeLookups As IEnumerable(Of RouteLookup) = From rt In db.RouteLookups Select rt

    For Each rtLookUp As RouteLookup In routeLookups
        Dim parameterizedURL As String = BuildParameterizedVirtualPath(rtLookUp)

            ' Determine handler and route values
            If rtLookUp.RouteHandler Is Nothing Then
                RouteTable.Routes.Add(rtLookUp.RouteName, New BaseRoute(parameterizedURL, New BaseRouteHandler(), rtLookUp))
            Else
                RouteTable.Routes.Add(rtLookUp.RouteName, New BaseRoute(parameterizedURL, Activator.CreateInstance(Type.GetType("QA." + rtLookUp.RouteHandler)), rtLookUp))
            End If            
    Next
End Sub

Protected Shared Function BuildParameterizedVirtualPath(rtLookUp As RouteLookup) As String

    Dim parameterizedURL As String = rtLookUp.RelativePath
    For Each param As RouteParameter In rtLookUp.RouteParameters
        parameterizedURL &= "/{" + param.Name + "}"
    Next
    Return parameterizedURL

End Function

Public Shared Sub RedirectToRoutePermanent(rtData As RouteData)

    Dim route As BaseRoute = DirectCast(rtData.Route, BaseRoute)
    Dim rtLookup As RouteLookup = route.RouteLookup
    Dim newRtLookupID As Integer = rtLookup.RedirectedToRoute
    Dim newRtLookup As RouteLookup = (From rt In db.RouteLookups Where rt.RouteLookupID = newRtLookupID).SingleOrDefault
    HttpContext.Current.Response.RedirectToRoutePermanent(newRtLookup.RouteName, rtData.Values.Values)

End Sub
End Class

自定义路线类：

Public Class BaseRoute
Inherits Route

Private _routeLookup As RouteLookup = Nothing

Public Sub New(url As String, routeHandler As IRouteHandler, routeLookup As RouteLookup)
    MyBase.New(url, routeHandler)
    _routeLookup = routeLookup

End Sub

Public ReadOnly Property RouteLookup As RouteLookup
    Get
        Return _routeLookup
    End Get
End Property
End Class

自定义RouteHandler：

Public Class BaseRouteHandler
Implements IRouteHandler

Protected _baseRoute As BaseRoute = Nothing
Protected _rtLookup As RouteLookup = Nothing

Protected Overridable Sub InitializeContext(ByVal requestContext As System.Web.Routing.RequestContext)

    _baseRoute = DirectCast(requestContext.RouteData.Route, BaseRoute)
    _rtLookup = _baseRoute.RouteLookup

End Sub


Public Function GetHttpHandler(ByVal requestContext As System.Web.Routing.RequestContext) _
                        As System.Web.IHttpHandler Implements System.Web.Routing.IRouteHandler.GetHttpHandler

    InitializeContext(requestContext)
    EnforceURLStandard(requestContext)
    PerformRedirectIfNeeded(requestContext)
    Return GetPageHandler(requestContext)

End Function


Protected Overridable Sub PerformRedirectIfNeeded(ByVal requestContext As System.Web.Routing.RequestContext)

    If _rtLookup.RedirectedToRoute > 0 Then
        PageRouter.RedirectToRoutePermanent(requestContext.RouteData)
    End If

End Sub


Protected Sub EnforceURLStandard(ByVal requestContext As System.Web.Routing.RequestContext)

    ' Test for:
    '   * Proper protocol
    '   * www. exists
    '   * must be all lowercase

    Dim scheme As String = HttpContext.Current.Request.Url.GetComponents(UriComponents.Scheme, UriFormat.UriEscaped)
    Dim rightSide As String = HttpContext.Current.Request.Url.GetComponents(UriComponents.HostAndPort Or UriComponents.PathAndQuery, UriFormat.UriEscaped)
    Dim newURL As String = Nothing

    If Not rightSide.ToLower().StartsWith("www.") AndAlso Not rightSide.ToLower().StartsWith("localhost") _
        AndAlso Not rightSide.ToLower().StartsWith("uat") AndAlso Not rightSide.ToLower().StartsWith("ux") Then
        newURL = scheme & "://www." & rightSide
    End If

    If _rtLookup.IsSecure <> requestContext.HttpContext.Request.IsSecureConnection Then
        Dim newScheme As String = If(_rtLookup.IsSecure, "https", "http")
        newURL = newScheme & rightSide
    End If

    Dim pattern As String = "[A-Z]"
    If Not String.IsNullOrWhiteSpace(newURL) Then
        If Regex.IsMatch(newURL, pattern) Then
            newURL = newURL.ToLower()
        End If
    Else
        If Regex.IsMatch(HttpContext.Current.Request.Url.ToString(), pattern) Then
            newURL = HttpContext.Current.Request.Url.ToString().ToLower()
        End If
    End If

    If Not newURL Is Nothing Then
        HttpContext.Current.Response.RedirectPermanent(newURL, True)
    End If

End Sub

Protected Overridable Function GetPageHandler(ByVal requestContext As System.Web.Routing.RequestContext) As System.Web.IHttpHandler

    Return TryCast(BuildManager.CreateInstanceFromVirtualPath("/" & _rtLookup.RequestHandler, GetType(Page)), Page)

End Function

End Class

Answer 1

好吧，弄清楚这里发生了什么。 RedirectToRoutePermanent不会像RedirectPermanent（url，true）那样终止请求。我重写了PageRouter.RedirectToRoutePermanent，解决了这个问题：

 Public Shared Sub RedirectToRoutePermanent(rtData As RouteData)

    Dim route As BaseRoute = DirectCast(rtData.Route, BaseRoute)
    Dim rtLookup As RouteLookup = route.RouteLookup
    Dim newRtLookupID As Integer = rtLookup.RedirectedToRoute
    Dim newRtLookup As RouteLookup = (From rt In db.RouteLookups Where rt.RouteLookupID = newRtLookupID).SingleOrDefault

    Dim hostAndPort As String = HttpContext.Current.Request.Url.GetComponents(UriComponents.HostAndPort, UriFormat.UriEscaped)
    Dim newURL As String = Nothing

    Dim scheme As String = If(rtLookup.IsSecure, "https", "http")
    newURL = scheme & "://" & hostAndPort
    newURL &= "/" & newRtLookup.RelativePath

    If rtData.Values.Count > 1 Then
        For i As Integer = 1 To rtData.Values.Count - 1
            newURL &= "/" & rtData.Values(i)
        Next
    End If

    HttpContext.Current.Response.RedirectPermanent(newURL, True)

End Sub

为什么RedirectToRoutePermanent将“count = 0”添加到查询字符串？

1 个答案: