Screen |
provides information about the
display |
Availability
JavaScript 1.2
Synopsis
screen
Properties
- availHeight
-
Specifies
the available height, in pixels, of the screen on which the web
browser is displayed. On operating systems such as Windows, this
available height does not include vertical space allocated to
semipermanent features, such as the task bar at the bottom of the
screen.
- availLeft [Netscape 4]
-
Specifies the leftmost X-coordinate that is not allocated to a
semipermanent display feature, such as an application shortcut bar or
the Windows 95 task bar.
- availTop [Netscape 4]
-
Specifies the topmost Y-coordinate that is not allocated to a
semipermanent display feature, such as an application shortcut bar or
the Windows 95 task bar.
- availWidth
-
Specifies the available width, in pixels, of the screen on which the
web browser is displayed. On operating systems such as Windows, this
available width does not include horizontal space allocated to
semipermanent features, such as application shortcut bars.
- colorDepth
-
Specifies the base-2 logarithm of the number of colors allocated by
the web browser and available for displaying images. For example, if
a browser preallocates 128 colors,
screen.colorDepth would be 7. On systems that do
not allocate color palettes, this value is the same as the number of
bits-per-pixel for the screen.
In IE 4, colorDepth specifies the color depth of
the screen in bits-per-pixel, rather than the depth of a preallocated
color palette. The screen.pixelDepth property
provides this value in Netscape.
- height
-
Specifies the total height, in pixels, of the screen on which the web
browser is displayed. See also availHeight.
- pixelDepth [Netscape 4]
-
Specifies the color depth, in bits-per-pixel, of the screen on which
the web browser is displayed. Contrast with
colorDepth.
- width
-
Specifies the total width, in pixels, of the screen on which the web
browser is displayed. See also availWidth.
Description
The screen property of every Window refers to a
Screen object. The static properties of this global object contain
information about the screen on which the browser is displayed.
JavaScript programs can use this information to optimize their output
to match the user's display capabilities. For example, a
program can choose between large and small images based on the
display size and between 16-bit color images and 8-bit color images
based on the screen's color depth. A JavaScript program can
also use the information about the size of the screen to center new
browser windows on the screen.
See Also
The screen property of the Window object
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