PdfViewerControl.FormFieldValueChanging Event

Occurs when an end-user starts to edit an interactive form field value.

Namespace: DevExpress.Xpf.PdfViewer

Assembly: DevExpress.Xpf.PdfViewer.v21.2.dll

NuGet Package: DevExpress.Wpf.PdfViewer

Declaration

C#

public event FormFieldValueChangingEventHandler FormFieldValueChanging

VB.NET

Public Event FormFieldValueChanging As FormFieldValueChangingEventHandler

Event Data

The FormFieldValueChanging event's data class is FormFieldValueChangingEventArgs. The following properties provide information specific to this event:

Property	Description
Cancel	Specifies a value indicating whether to cancel changing the form field value.
FieldName	Gets the name of the form field.
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.
NewValue	Gets or sets a new value of the form field.
OldValue	Gets the form field’s previous value.
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.
Source	Gets or sets a reference to the object that raised the event. Inherited from RoutedEventArgs.

The event data class exposes the following methods:

Method	Description
InvokeEventHandler(Delegate, Object)	When overridden in a derived class, provides a way to invoke event handlers in a type-specific way, which can increase efficiency over the base implementation. Inherited from RoutedEventArgs.
OnSetSource(Object)	When overridden in a derived class, provides a notification callback entry point whenever the value of the Source property of an instance changes. Inherited from RoutedEventArgs.