DataSet.HasChanges Method

System.Data Namespace DataSet Class

Checks whether the DataSet has changes, including new, deleted, or modified rows.

1. Checks whether the DataSet has changes, including new, deleted, or modified rows.

[ VB ] Overloads Public Function HasChanges ( ) As Boolean

[ C# ] public bool HasChanges ( );

[ C++ ] public: bool HasChanges ( );

[ JScript ] public function HasChanges ( ) : Boolean;

2. Checks whether the DataSet has changes, including new, deleted, or modified rows, filtered by DataRowState.

[ VB ] Overloads Public Function HasChanges ( DataRowState ) As Boolean

[ C# ] public bool HasChanges ( DataRowState );

[ C++ ] public: bool HasChanges ( DataRowState );

[ JScript ] public function HasChanges ( DataRowState ) : Boolean;

The following example uses the GetChanges method to create a second DataSet object that is then used to update a DBMS.

NOTE: This example uses one of the overloaded versions of HasChanges. For other examples that may be available, see the individual overload topics.

private void UpdateDataSet ( DataSet myDataSet ) {
   // check for changes with the HasChanges method first.
   if ( !myDataSet.HasChanges ( DataRowState.Modified ) return;
   // create temporary DataSet variable.
   DataSet xDataSet;
   // getChanges for modified rows only.
   xDataSet = myDataSet.GetChanges ( DataRowState.Modified );
   // check the DataSet for errors.
   if ( xDataSet.HasErrors ) {
      // ... insert code to resolve errors here ...
  }
   // after fixing errors, update db with the DataAdapter used to fill the DataSet.
   myDataAdapter.Update ( xDataSet );
}

Private Sub UpdateDataSet ( ByVal myDataSet As DataSet )
   ' check for changes with the HasChanges method first.
   If Not myDataSet.HasChanges ( DataRowState.Modified ) Then Exit Sub
   ' create temporary DataSet variable.
   Dim xDataSet As DataSet
   ' getChanges for modified rows only.
   xDataSet = myDataSet.GetChanges ( DataRowState.Modified )
   ' check the DataSet for errors.
   If xDataSet.HasErrors Then
      ' ... insert code to resolve errors here ...
   End If
   ' after fixing errors, update db with the DataAdapter used to fill the DataSet.
   myDataAdapter.Update ( xDataSet )
End Sub

DataSet Members GetChanges HasErrors

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DataSet.HasChanges Method

Overload List

Example

See Also