Screen

Screen 介面表示了一個用戶端螢幕，通常是指呈現目前頁面的視窗。

一般來說為顯示目前網頁的視窗，可以透過 window.screen 取得物件實體。

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.onorientationchange

A handler for the orientationchange events.

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()

Registers an event handler of a specific event type on the EventTarget.

EventTarget.removeEventListener()

Removes an event listener from the EventTarget.

EventTarget.dispatchEvent()

Dispatches an event to this EventTarget.

Mozilla includes a couple of extensions for use by JS-implemented event targets to implement onevent properties. See also WebIDL bindings.

• void setEventHandler(DOMString type, EventHandler handler)
• EventHandler getEventHandler(DOMString type)

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