Screen

Screen 接口表示一个屏幕，往往是在当前正在被渲染的window对象上面，并且可以使用 window.screen 获取它。

Note that browsers determine which screen to report as current by detecting which screen has the center of the browser window.

Properties

Screen.availTop: Specifies the y-coordinate of the first pixel that is not allocated to permanent or semipermanent user interface features.
Screen.availLeft: Returns the first available pixel available from the left side of the screen.
Screen.availHeight: Specifies the height of the screen, in pixels, minus permanent or semipermanent user interface features displayed by the operating system, such as the Taskbar on Windows.
Screen.availWidth: Returns the amount of horizontal space in pixels available to the window.
Screen.colorDepth: Returns the color depth of the screen.
Screen.height: Returns the height of the screen in pixels.
Screen.left: Returns the distance in pixels from the left side of the main screen to the left side of the current screen.
Screen.orientation: Returns the current orientation of the screen.
Screen.pixelDepth: Gets the bit depth of the screen.
Screen.top: Returns the distance in pixels from the top side of the current screen.
Screen.width: Returns the width of the screen.
Screen.mozEnabled: Boolean. Setting to false will turn off the device's screen.
Screen.mozBrightness: Controls the brightness of a device's screen. A double between 0 and 1.0 is expected.

Screen.lockOrientation: Lock the screen orientation (only works in fullscreen or for installed apps)
Screen.unlockOrientation: Unlock the screen orientation (only works in fullscreen or for installed apps)

Methods inherit from EventTarget

EventTarget.addEventListener(): Register an event handler of a specific event type on the EventTarget.
EventTarget.removeEventListener(): Removes an event listener from the EventTarget.
EventTarget.dispatchEvent(): Dispatch an event to this EventTarget.

Mozilla extensions for use by JS-implemented event targets to implement on* properties. See also WebIDL bindings.

if (screen.pixelDepth < 8) {
  // use low-color version of page
} else { 
  // use regular, colorful page
}

CSSOM View