Validating XML using DTD

Question

User-1895243249 posted

Howdy all,

Got myself a bit of a problem. I'm trying to validate an XML file using a DTD using the following code from http://msdn.microsoft.com/en-us/library/z2adhb2f.aspx?cs-save-lang=1&cs-lang=vb#code-snippet-1

    Private Sub BTN_ValidateXMLdoc_Click(sender As Object, e As EventArgs) Handles BTN_ValidateXMLdoc.Click

        Dim JobNumber As String = Me.HNF_JobName.Value
        Dim XMLPath As String = "N:\" & JobNumber & "\" & JobNumber & ".xml"


        ' Set the validation settings.
        Dim settings As XmlReaderSettings = New XmlReaderSettings()
        settings.DtdProcessing = DtdProcessing.Parse
        settings.ValidationType = ValidationType.DTD
        settings.ValidationFlags = XmlSchemaValidationFlags.ReportValidationWarnings
        settings.ValidationFlags = XmlSchemaValidationFlags.ProcessInlineSchema
        AddHandler settings.ValidationEventHandler, AddressOf ValidationCallBack

        ' Create the XmlReader object.
        Dim reader As XmlReader = XmlReader.Create(XMLPath, settings)

        ' Parse the file. 
        While reader.Read()
        End While

    End Sub

  ' Display any validation errors.
    Private Shared Sub ValidationCallBack(sender As Object, e As ValidationEventArgs)
        MsgBox(String.Format("Validation Error: {0}", e.Message), MsgBoxStyle.OkOnly)
    End Sub

Now, for some reason, and I have no idea what the reason is (hence me posting here) if an error occurs while reader.Read(), instead of the ValidationCallBack sub being called, it throws an exception error. Now I could be wrong but if there is a validation error while the reader.read() is executing, shouldn't the ValidationEventHandler be fired?