Problem in ASP.NET to throw an error and catch it in the global.asax

In an aspx web page I'm doing this:

Try

    Throw new IndexOutOfRangeException

Catch ex As Exception

    Dim myException As New bizException(ex)

    Throw myException

End Try

In the global.asax I'm doing this:

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

    Dim myException As bizException = DirectCast(Server.GetLastError().GetBaseException(), bizException)


End Sub

An this error is occuring during the cast:

InvalidCastException: Unable to cast object of type 'System.IndexOutOfRangeException' 开发者_JS百科to type 'bizException'.

The GetLastError's type is IndexOutOfRangeException and not bizException... Why ?

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In the "Application_Error" routine, Server.GetLastError() returns exceptions of type 'System.Web.HttpUnhandledException' because you did not handle the error earlier - i.e. at method or page level.

You need to examine the contents of "InnerException" from the exception returned by Server.GetLastError().

The "InnerException" will contain your "bizException".

Dim myException As bizException = DirectCast(Server.GetLastError().InnerException, bizException)

Not sure of the VB.NET syntax here - more of a C# person myself.

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Try this instead:

Dim myException As bizException = DirectCast(Server.GetLastError(), bizException)

(Removed "GetBaseException" call.)