Why would Guid.NewGuid() be generating an empty guid?

Question

I have a Guid.NewGuid() call that is creating an Empty Guid.

What would cause such a problem and how can I fix it?

Edit: The code:

<WebMethod()> _
Public Function CreateRow(rowValue As String) as String
    Dim rowPointer As Guid = System.Guid.NewGuid()
    Dim rowPointerValue As String = rowPointer.ToString()

    Try
        Dim result as Integer = SqlHelper.ExecuteNonQuery(ConnectionString, "Sproc_Name", rowValue, rowPointer)

        Return result
    Catch ex as Exception
        Throw ex
    End Try
End Function

Edit: Turns out that rowPointer was originally being passed to the SqlHelper and not rowPointerValue - This of course is passed as empty, as pointed out in the answers. Changing it to rowPointerValue/rowPointer.ToString() fixed the problem.

Answer 1

This is an old problem in VB.NET. It is only the debug visualizer that is broken.

http://www.thesoftwaredevotional.com/2008/12/guid-visualizer-broken-in-vbnet.html

Answer 2

I had the same thing. Debugging of Guid.NeGuid() was showing that it's empty. Calling .ToString() fixed the situation.

Answer 3

I tested this code in VS2008 and the results are not what I expected. It seems that the new guid is not created until the toString method is called. After stepping through the code rowPointerValue does hold a string representation of the guid.

It seems to be using defferred execution?

Answer 4

I've only experiened this problem in VB.NET and only while debugging. Thanks 48494, for that info.

Answer 5

Try this

Dim g As New Guid();

Dim whereDoYouWantToSeeIt As String = g.ToString();