'宣言 Public Class C1LeftAlignTool Inherits C1.WPF.RichTextBox.Ribbon.RichTextBoxToggleButtonTool(Of Nullable(Of C1TextAlignment)) Implements IUpdateableTool
public class C1LeftAlignTool : C1.WPF.RichTextBox.Ribbon.RichTextBoxToggleButtonTool<Nullable<C1TextAlignment>>, IUpdateableTool