{

public static class FullScreenHelper

{

private static Window _fullWindow;

private static WindowState _windowState;

private static WindowStyle _windowStyle;

private static bool _windowTopMost;

private static ResizeMode _windowResizeMode;

private static Rect _windowRect;

/// <summary>

/// 进入全屏

/// </summary>

/// <param name="window"></param>

public static void GoFullscreen(this Window window)

{

//已经是全屏

if(window.IsFullscreen()) return;

//存储窗体信息

_windowState = window.WindowState;

_windowStyle = window.WindowStyle;

_windowTopMost = window.Topmost;

_windowResizeMode = window.ResizeMode;

_windowRect.X = window.Left;

_windowRect.Y = window.Top;

_windowRect.Height = window.Width;

_windowRect.Height = window.Height;

//变成无边窗体

window.WindowState = WindowState.Normal;//假如已经是Maximized，就不能进入全屏，所以这里先调整状态

window.WindowStyle = WindowStyle.None;

window.ResizeMode = ResizeMode.NoResize;

window.Topmost = true;//最大化后总是在最上面

//获取窗口句柄

var handle = new WindowInteropHelper(window).Handle;

//获取当前显示器屏幕

Screen screen = Screen.FromHandle(handle);

//调整窗口最大化,全屏的关键代码就是下面3句

window.MaxWidth = screen.Bounds.Width;

window.MaxHeight = screen.Bounds.Height;

window.WindowState = WindowState.Maximized;

//解决切换应用程序的问题

window.Activated += new EventHandler(window_Activated);

window.Deactivated += new EventHandler(window_Deactivated);

//记住成功最大化的窗体

_fullWindow = window;

}

static void window_Deactivated(object sender, EventArgs e)

{

var window = sender as Window;

window.Topmost = false;

}

static void window_Activated(object sender, EventArgs e)

{

var window = sender as Window;

window.Topmost = true;

}

/// <summary>

/// 退出全屏

/// </summary>

/// <param name="window"></param>

public static void ExitFullscreen(this Window window)

{

//已经不是全屏无操作

if (!window.IsFullscreen()) return;

//恢复窗口先前信息，这样就退出了全屏

window.Topmost = _windowTopMost;

window.WindowStyle = _windowStyle;

window.ResizeMode = ResizeMode.CanResize;//设置为可调整窗体大小

window.Left = _windowRect.Left;

window.Width = _windowRect.Width;

window.Top = _windowRect.Top;

window.Height = _windowRect.Height;

window.WindowState = _windowState;//恢复窗口状态信息

window.ResizeMode = _windowResizeMode;//恢复窗口可调整信息

//移除不需要的事件

window.Activated -= window_Activated;

window.Deactivated -= window_Deactivated;

_fullWindow = null;

}

/// <summary>

/// 窗体是否在全屏状态

/// </summary>

/// <param name="window"></param>

/// <returns></returns>

public static bool IsFullscreen(this Window window)

{

if(window==null)

{

throw new ArgumentNullException("window");

}

return _fullWindow == window;

}

}

}