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BindingManagerBase.CancelCurrentEdit Method

  • Reference

Definition

Namespace:
System.Windows.Forms
Assembly:
System.Windows.Forms.dll

When overridden in a derived class, cancels the current edit.

public:
 abstract void CancelCurrentEdit();
public abstract void CancelCurrentEdit ();
abstract member CancelCurrentEdit : unit -> unit
Public MustOverride Sub CancelCurrentEdit ()

Examples

The following code example demonstrates both the CancelCurrentEdit and the EndCurrentEdit methods. When you call the CancelCurrentEdit methods, changes made to the data are discarded. When you call the EndCurrentEdit method, the changes are kept.

private:
   void CancelEdit()
   {
      // Gets the CurrencyManager which is returned when the
      // data source is a DataView.
      BindingManagerBase^ myMgr = dynamic_cast<CurrencyManager^>(BindingContext[ myDataView ]);

      // Gets the current row and changes a value. Then cancels the
      // edit and thereby discards the changes.
      DataRowView^ tempRowView = dynamic_cast<DataRowView^>(myMgr->Current);
      Console::WriteLine( "Original: {0}", tempRowView[ "myCol" ] );
      tempRowView[ "myCol" ] = "These changes will be discarded";
      Console::WriteLine( "Edit: {0}", tempRowView[ "myCol" ] );
      myMgr->CancelCurrentEdit();
      Console::WriteLine( "After CanceCurrentlEdit: {0}", tempRowView[ "myCol" ] );
   }

   void EndEdit()
   {
      // Gets the CurrencyManager which is returned when the
      // data source is a DataView.
      BindingManagerBase^ myMgr = dynamic_cast<CurrencyManager^>(BindingContext[ myDataView ]);
      
      // Gets the current row and changes a value. Then ends the
      // edit and thereby keeps the changes.
      DataRowView^ tempRowView = dynamic_cast<DataRowView^>(myMgr->Current);
      Console::WriteLine( "Original: {0}", tempRowView[ "myCol" ] );
      tempRowView[ "myCol" ] = "These changes will be kept";
      Console::WriteLine( "Edit: {0}", tempRowView[ "myCol" ] );
      myMgr->EndCurrentEdit();
      Console::WriteLine( "After EndCurrentEdit: {0}", tempRowView[ "myCol" ] );
   }

private void CancelEdit()
{
    // Gets the CurrencyManager which is returned when the
    // data source is a DataView.
    BindingManagerBase myMgr =
        (CurrencyManager) BindingContext[myDataView];

    // Gets the current row and changes a value. Then cancels the
    // edit and thereby discards the changes.
    DataRowView tempRowView = (DataRowView) myMgr.Current;
    Console.WriteLine("Original: {0}", tempRowView["myCol"]);
    tempRowView["myCol"] = "These changes will be discarded";
    Console.WriteLine("Edit: {0}", tempRowView["myCol"]);
    myMgr.CancelCurrentEdit();
    Console.WriteLine("After CanceCurrentlEdit: {0}",
        tempRowView["myCol"]);
}

private void EndEdit()
{
    // Gets the CurrencyManager which is returned when the
    // data source is a DataView.
    BindingManagerBase myMgr =
        (CurrencyManager) BindingContext[myDataView];

    // Gets the current row and changes a value. Then ends the
    // edit and thereby keeps the changes.
    DataRowView tempRowView = (DataRowView) myMgr.Current;
    Console.WriteLine("Original: {0}", tempRowView["myCol"]);
    tempRowView["myCol"] = "These changes will be kept";
    Console.WriteLine("Edit: {0}", tempRowView["myCol"]);
    myMgr.EndCurrentEdit();
    Console.WriteLine("After EndCurrentEdit: {0}",
        tempRowView["myCol"]);
}

Private Sub CancelEdit()
    ' Gets the CurrencyManager which is returned when the 
    ' data source is a DataView.
    Dim myMgr As BindingManagerBase = _
    CType(BindingContext(myDataView), CurrencyManager)

    ' Gets the current row and changes a value. Then cancels the 
    ' edit and thereby discards the changes.
    Dim tempRowView As DataRowView = _
    CType(myMgr.Current, DataRowView)
    Console.WriteLine("Original: {0}", tempRowView("myCol"))
    tempRowView("myCol") = "These changes will be discarded"
    Console.WriteLine("Edit: {0}", tempRowView("myCol"))
    myMgr.CancelCurrentEdit()
    Console.WriteLine("After CanceCurrentlEdit: {0}", _
    tempRowView("myCol"))
End Sub

Private Sub EndEdit()
    ' Gets the CurrencyManager which is returned when the 
    ' data source is a DataView.
    Dim myMgr As BindingManagerBase = _
    CType(BindingContext(myDataView), CurrencyManager)

    ' Gets the current row and changes a value. Then ends the 
    ' edit and thereby keeps the changes.
    Dim tempRowView As DataRowView = _
    CType(myMgr.Current, DataRowView)
    Console.WriteLine("Original: {0}", tempRowView("myCol"))
    tempRowView("myCol") = "These changes will be kept"
    Console.WriteLine("Edit: {0}", tempRowView("myCol"))
    myMgr.EndCurrentEdit()
    Console.WriteLine("After EndCurrentEdit: {0}", _
    tempRowView("myCol"))
End Sub

Remarks

This method is supported only if the data source implements the IEditableObject interface. If the object does not implement the IEditableObject interface, changes made to the data will not be discarded.

Calling the CancelCurrentEdit method causes the Format event to occur.

Applies to

See also