TreeListView.InvalidNodeException Event

Fires when a node fails validation, or when it cannot be saved to a data source.

Namespace: DevExpress.Xpf.Grid

Assembly: DevExpress.Xpf.Grid.v14.2.dll

Declaration

C#

public event TreeListInvalidNodeExceptionEventHandler InvalidNodeException

VB.NET

Public Event InvalidNodeException As TreeListInvalidNodeExceptionEventHandler

Event Data

The InvalidNodeException event's handler receives an argument of the TreeListInvalidNodeExceptionEventArgs type. The following properties provide information specific to this event:

Property	Description
ErrorText	Gets or sets the error description.
Exception	Gets the exception that raised the TreeListView.InvalidNodeException event.
ExceptionMode	Gets or sets a value that specifies how an exception should be handled.
Handled	Gets or sets a value that indicates the present state of the event handling for a routed event as it travels the route. Inherited from RoutedEventArgs.
Node	Gets the processed node. Inherited from TreeListNodeEventArgs.
OriginalSource	Gets the original reporting source as determined by pure hit testing, before any possible Source adjustment by a parent class. Inherited from RoutedEventArgs.
RoutedEvent	Gets or sets the RoutedEvent associated with this RoutedEventArgs instance. Inherited from RoutedEventArgs.
Row	Gets the processed row. Inherited from TreeListNodeEventArgs.
Source	Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs.
WindowCaption	Gets or sets the error window's caption.

Remarks

Node validation is performed within the TreeListView.ValidateNode event handler, when a node is about to lose focus. The InvalidNodeException event allows you to override the default error presentation. This event occurs after the TreeListView.ValidateNode event (provided that the focused node's validation has failed).

Use the event parameter's TreeListInvalidNodeExceptionEventArgs.ExceptionMode property, to specify the action performed in response to entering an invalid value. You can display a message box with an error description, suppress any action, throw an exception or discard new data and revert to an old value.

To learn more, see Validating Rows.