'宣言 Public Class C1DecreaseFontSizeTool Inherits C1ButtonTool Implements Windows.UI.Xaml.Controls.ICommandBarElement, Windows.UI.Xaml.Controls.ICommandBarElement2
public class C1DecreaseFontSizeTool : C1ButtonTool, Windows.UI.Xaml.Controls.ICommandBarElement, Windows.UI.Xaml.Controls.ICommandBarElement2