DXCommonDialog.HelpRequest Event

Occurs when the user clicks the Help button on a file dialog and allows you to provide a help link or cancel opening help resources.

Namespace: DevExpress.Xpf.Dialogs

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

NuGet Package: DevExpress.Wpf.Dialogs

Declaration

C#

public event HelpRequestEventHandler HelpRequest

VB.NET

Public Event HelpRequest As HelpRequestEventHandler

Event Data

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

Property	Description
Cancel	Gets or sets a value indicating whether the event should be canceled. Inherited from CancelEventArgs.
HelpLink	Gets or sets a help link that is opened when an end-user clicks the help button.

Remarks

The HelpRequest event is raised when an end user presses the help button. The help button is available when the DXFileDialog.ShowHelp property is set to true.

Use the HelpRequest event to provide a help link for end users (using the HelpRequestEventArgs.HelpLink property) or cancel opening help resources.

Note

The provided link is opened using the Process.Start method.

The code sample below demonstrates how to provide a custom help link by handling the HelpRequest event.

C#

private void button_Click(object sender, RoutedEventArgs e) {
    var fileDialog = new DXSaveFileDialog();
    fileDialog.Filter = "Image Files|*.BMP;*.JPG;*.GIF|All files|*.*";
    fileDialog.ShowHelp = true;
    fileDialog.HelpRequest += FileDialog_HelpRequest;
    fileDialog.ShowDialog();
}

private void FileDialog_HelpRequest(object sender, HelpRequestEventArgs e) {
    e.HelpLink = "https://docs.devexpress.com";
}

VB.NET

Private Sub button_Click(ByVal sender As Object, ByVal e As RoutedEventArgs)
    Dim fileDialog = New DXSaveFileDialog()
    fileDialog.Filter = "Image Files|*.BMP;*.JPG;*.GIF|All files|*.*"
    fileDialog.ShowHelp = True
    fileDialog.HelpRequest += FileDialog_HelpRequest
    fileDialog.ShowDialog()
End Sub

Private Sub FileDialog_HelpRequest(ByVal sender As Object, ByVal e As HelpRequestEventArgs)
    e.HelpLink = "https://docs.devexpress.com"
End Sub