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.
Assembly: System.Data (in System.Data.dll)
Parameters
- rowStates
-
Type:
System.Data.DataRowState
One of the DataRowState values.
Return Value
Type: System.Data.DataSetA 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 null.
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 null.
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
Available since 1.1