private void FullOrMin(Window window)
{
// 如果是全屏,则窗口
if (window.WindowState == WindowState.Maximized)
{
window.Topmost = false;
window.WindowState = WindowState.Normal;
window.WindowStyle = WindowStyle.SingleBorderWindow;

// 设置为可调整窗体大小
window.ResizeMode = ResizeMode.CanResizeWithGrip;
window.Width = 800;
window.Height = 600;

// 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);

window.Left = (SystemParameters.PrimaryScreenWidth - window.Width) / 2;//(screen.Bounds.Width - window.Width) / 2;
window.Top = (SystemParameters.PrimaryScreenHeight - window.Height) / 2;//(screen.Bounds.Height - window.Height) / 2;

//window.WindowState = WindowState.Minimized;
return;
}

// 如果是窗口,则全屏
if (window.WindowState == WindowState.Normal)
{
// 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;

// 最大化后总是在最上面
window.Topmost = true;

//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
window.MaxWidth = SystemParameters.PrimaryScreenWidth;
window.MaxHeight = SystemParameters.PrimaryScreenHeight;
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);
}

}

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;
}

//调用(窗口状态下调用就是全屏,全屏调用就是窗口),调的时候把窗口或者关闭的代码也写上,不然没有关闭的地方

FullOrMin(this);//可以根据自己的需求再改改