DataDOMEvent.IsUndoRedo Property

Definition

Gets a value indicating whether the data validation event occurs during an undo operation or a redo operation.

public:
 property bool IsUndoRedo { bool get(); };
public bool IsUndoRedo { get; }
member this.IsUndoRedo : bool
Public ReadOnly Property IsUndoRedo As Boolean

Property Value

Examples

In the following example, the IsUndoRedo property is used to determine whether the event is occurring during an undo or redo operation. If it is, the event handler is exited using the return statement, otherwise the custom function Calculate is called:

public void field1_OnAfterChange(DataDOMEvent e)
{
 if (e.<span class="label">IsUndoRedo</span>)
 {
  // An undo or redo operation has occurred and the DOM is read-only.
  return;
 }
 Calculate();
}

Remarks

When an undo or a redo operation takes place, the form's underlying XML document is placed in a read-only state and cannot be modified. This can sometimes occur during an OnAfterChange event; when it does, the IsUndoRedo property is used to bypass the data validation that it contains.

Applies to