TypeDataTable dt = dv.Table as TypeDataTable; DataSet ds = new DataSet(); ds.Merge(dt, true,MissingSchemaAction.Add); return ds;
Gary Davidson
From: Kirk Allen Evans <[EMAIL PROTECTED]> Reply-To: "Moderated discussion of advanced .NET topics." <[EMAIL PROTECTED]> To: [EMAIL PROTECTED] Subject: [ADVANCED-DOTNET] DataTable.Clone and NullReferenceException Date: Thu, 22 Jan 2004 18:30:25 -0500
I am using an API that exposes a DataView of a typed DataTable, I have no control over this API. The DataTable that I am trying to use already belongs to a typed DataSet. I need to import the DataTable to another DataSet to be able to work with it.
Tried using ds.Merge(table). Internally, .Merge calls the .Clone method on the table being merged in. For some reason, .Clone throws a NullReferenceException when .Clone is called. I verified that the table has both rows and columns, and the code decompile for System.Data.DataTable in Reflector didn't show anything obvious that would cause the exception.
//Calling code private DataSet GetDS(DataView dv) { DataTable dt = dv.Table; DataSet ds = new DataSet(); ds.Merge(dt); return ds; }
'Pseudo class Public Class fooTable Inherits DataTable
Public Overrides Function ToString() As String Return Me.TableName & "foo" End Function
Public Overrides Function Clone() As DataTable 'Following line throws the exception Dim dt As DataTable = MyBase.Clone()
Dim cln As fooTable = CType(dt, fooTable) cln.TableName = Me.ToString() Return cln End Function End Class
So, has anyone see a case where an inherited DataTable could throw a NullReferenceException in the .Clone method?
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=================================== This list is hosted by DevelopMentor� http://www.develop.com Some .NET courses you may be interested in:
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