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Class (inherits from WebUIControl)

New in 2012r2

WebCanvas controls are very useful for implementing your own graphical controls because you can use the WebGraphics class to draw inside the WebCanvas region.

Closed Opening Shown
ContextualMenuSelected Paint
Hidden Pressed
Close Invalidate UpdateBrowser
ExecuteJavaScript Refresh
GotoURL SetFocus
ContextualMenu LockBottom fa-lock-32.png Parent fa-lock-32.png
ControlID fa-lock-32.png LockHorizontal fa-lock-32.png Style
DiffEngineDisabled LockLeft fa-lock-32.png TabIndex
Enabled LockRight fa-lock-32.png Tooltip
Height LockVertical fa-lock-32.png Top
Indicator Name fa-lock-32.png Visible
Left Page fa-lock-32.png Width


Remember: Browsers maintain an uncompressed raster image of the contents of the canvas in memory so it can be displayed to the user. A 1024x1024 pixel canvas requires 4MB of RAM (4 bytes of color data per pixel). A browser may refuse a request to create a canvas that is too large. For instance iOS5 has a memory limit of 10MB for a single web page (it has been increased to 25MB in iOS6). On a Retina display, canvases require 4 times as much memory as a non-retina display.

Unlike the DesktopCanvas, the WebCanvas cannot act as a parent control to other web controls.

See Also

WebGraphics, Graphics classes; UserGuide:Web Canvas topic