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DataSet.GetChanges Method (DataRowState)

Gets a copy of the DataSet containing all changes made to it since it was last loaded, or since AcceptChanges was called, filtered by DataRowState.

Namespace:  System.Data
Assembly:  System.Data (in System.Data.dll)

'Declaration
Public Function GetChanges ( _
	rowStates As DataRowState _
) As DataSet

Parameters

rowStates
Type: System.Data.DataRowState

One of the DataRowState values.

Return Value

Type: System.Data.DataSet
A filtered copy of the DataSet that can have actions performed on it, and subsequently be merged back in using Merge. If no rows of the desired DataRowState are found, the method returns Nothing.

The GetChanges method is used to produce a second DataSet object that contains only the changes introduced into the original. Use the rowStates argument to specify the type of changes the new object should include.

This returned copy is designed to be merged back in to this original DataSet. Relationship constraints may cause parent rows marked Unchanged to be included. If no rows of the desired DataRowState are found, the GetChanges method returns Nothing.

The following example uses the GetChanges method to create a second DataSet object, which is then used to update a data source.

Private Sub UpdateDataSet(ByVal dataSet As DataSet)
   ' Check for changes with the HasChanges method first. 
   If Not dataSet.HasChanges(DataRowState.Modified) Then  
       Exit Sub 
   End If 

   ' Create temporary DataSet variable and 
   ' GetChanges for modified rows only. 
   Dim tempDataSet As DataSet = _
       dataSet.GetChanges(DataRowState.Modified)

   ' Check the DataSet for errors. 
   If tempDataSet.HasErrors Then 
      ' Insert code to resolve errors. 
   End If 

   ' After fixing errors, update the data source with    
   ' the DataAdapter used to create the DataSet.
   adapter.Update(tempDataSet)
End Sub

.NET Framework

Supported in: 4.6, 4.5, 4, 3.5, 3.0, 2.0, 1.1

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

XNA Framework

Supported in: 3.0, 2.0, 1.0
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