Is there a way to change the original value in the DataRow?
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Is there any way to change the original value in the DataRow? DataRow.Item(0) may have modified/current value and its original value. I need to change its original value like row.Item("ColumnName", DataRowVersion.Original) = "NewValue". But this property is for read only any. Ideas? I have found the way but I don't like it and it looks like a hack. Here's the code:
Public Function SetRowOriginalItemValue(ByVal primaryKeyColumn As DataColumn, ByVal key As Object, ByVal editColumn As DataColumn, ByVal value As Object) As Boolean 'Utils.Assert.ArgumentCheckForNullReference(primaryKeyColumn, "primaryKeyColumn") 'Utils.Assert.ArgumentCheckForNullReference(key, "key") 'Utils.Assert.ArgumentCheckForNullReference(editColumn, "editColumn") 'Utils.Assert.ArgumentCheckExpectedType(key, primaryKeyColumn.DataType) 'Utils.Assert.ArgumentCheckExpectedType(value, editColumn.DataType) Dim t As DataTable = editColumn.Table Dim d As DataSet = t.DataSet Dim s As New IO.MemoryStream d.WriteXml(s, XmlWriteMode.DiffGram) s.Seek(0, IO.SeekOrigin.Begin) Dim doc As New Xml.XmlDocument doc.Load(s) Dim nsmgr As Xml.XmlNamespaceManager = New Xml.XmlNamespaceManager(doc.NameTable) nsmgr.AddNamespace("diffgr", "urn:schemas-microsoft-com:xml-diffgram-v1") nsmgr.AddNamespace("my", d.Namespace) Dim xp As String = String.Format(New Globalization.CultureInfo("en-US"), _ "/diffgr:diffgram/diffgr:before/my:{0}[starts-with(@diffgr:id, '{0}')]/my:{1}[text()='{2}']/../my:{3}/node()", _ t.TableName, primaryKeyColumn.ColumnName, key, editColumn.ColumnName) Dim n As Xml.XmlNode = doc.DocumentElement.SelectSingleNode(xp, nsmgr) If Not n Is Nothing Then n.Value = value d.Clear() d.ReadXml(New IO.StringReader(doc.InnerXml), XmlReadMode.DiffGram) Return True End If Return False End Function '''''''''''''''''''' Sub SetRowOriginalItemValueTest() Dim d As New DistrictSet Dim row As DistrictSet.DistrictsRow row = d.Districts.NewDistrictsRow row.DistrictId = 109901 row.DistrictName = "Orange County" d.Districts.AddDistrictsRow(row) d.AcceptChanges() d.Districts(0).DistrictName = "West Coast" Diagnostics.Trace.WriteLine("Current: " & d.Districts.Item(0)("DistrictName")) Diagnostics.Trace.WriteLine("Original before SetRowOriginalItemValue(): " & d.Districts.Item(0)("DistrictName", DataRowVersion.Original)) SetRowOriginalItemValue(d.Districts.DistrictIdColumn, 109901, d.Districts.DistrictNameColumn, "Northeast") -
Is there any way to change the original value in the DataRow? DataRow.Item(0) may have modified/current value and its original value. I need to change its original value like row.Item("ColumnName", DataRowVersion.Original) = "NewValue". But this property is for read only any. Ideas? I have found the way but I don't like it and it looks like a hack. Here's the code:
Public Function SetRowOriginalItemValue(ByVal primaryKeyColumn As DataColumn, ByVal key As Object, ByVal editColumn As DataColumn, ByVal value As Object) As Boolean 'Utils.Assert.ArgumentCheckForNullReference(primaryKeyColumn, "primaryKeyColumn") 'Utils.Assert.ArgumentCheckForNullReference(key, "key") 'Utils.Assert.ArgumentCheckForNullReference(editColumn, "editColumn") 'Utils.Assert.ArgumentCheckExpectedType(key, primaryKeyColumn.DataType) 'Utils.Assert.ArgumentCheckExpectedType(value, editColumn.DataType) Dim t As DataTable = editColumn.Table Dim d As DataSet = t.DataSet Dim s As New IO.MemoryStream d.WriteXml(s, XmlWriteMode.DiffGram) s.Seek(0, IO.SeekOrigin.Begin) Dim doc As New Xml.XmlDocument doc.Load(s) Dim nsmgr As Xml.XmlNamespaceManager = New Xml.XmlNamespaceManager(doc.NameTable) nsmgr.AddNamespace("diffgr", "urn:schemas-microsoft-com:xml-diffgram-v1") nsmgr.AddNamespace("my", d.Namespace) Dim xp As String = String.Format(New Globalization.CultureInfo("en-US"), _ "/diffgr:diffgram/diffgr:before/my:{0}[starts-with(@diffgr:id, '{0}')]/my:{1}[text()='{2}']/../my:{3}/node()", _ t.TableName, primaryKeyColumn.ColumnName, key, editColumn.ColumnName) Dim n As Xml.XmlNode = doc.DocumentElement.SelectSingleNode(xp, nsmgr) If Not n Is Nothing Then n.Value = value d.Clear() d.ReadXml(New IO.StringReader(doc.InnerXml), XmlReadMode.DiffGram) Return True End If Return False End Function '''''''''''''''''''' Sub SetRowOriginalItemValueTest() Dim d As New DistrictSet Dim row As DistrictSet.DistrictsRow row = d.Districts.NewDistrictsRow row.DistrictId = 109901 row.DistrictName = "Orange County" d.Districts.AddDistrictsRow(row) d.AcceptChanges() d.Districts(0).DistrictName = "West Coast" Diagnostics.Trace.WriteLine("Current: " & d.Districts.Item(0)("DistrictName")) Diagnostics.Trace.WriteLine("Original before SetRowOriginalItemValue(): " & d.Districts.Item(0)("DistrictName", DataRowVersion.Original)) SetRowOriginalItemValue(d.Districts.DistrictIdColumn, 109901, d.Districts.DistrictNameColumn, "Northeast")Apply DataTable.Rows[0].AcceptChanges()