rovf Posted November 4, 2013 Share Posted November 4, 2013 Sorry, this is really a beginner's question:I stumbled over the following piece of JavaScript code:var ctx=element.getElementsByTagName('canvas')[0].getContext('2d')...var w=ctx.canvas.widthI understand what the code is doing. However, I was surprised to find, that we can extract the canvas out of the context (i.e. ctx.canvas), because when looking at http://www.w3schools.com/tags/ref_canvas.aspI find the following:"This reference will cover the properties and methods of the getContext("2d") object"but looking below, I do not find an attribute "canvas" listed. Did I misunderstand the documentation, i.e. are there maybe even more attributes or methods available for the context object, than are listed on ref_canvas.asp? Or why has the "canvas" attribute been left out? Link to comment Share on other sites More sharing options...
justsomeguy Posted November 4, 2013 Share Posted November 4, 2013 The canvas property is a back-reference to the canvas from which the context was created. Check the MDN reference for the canvas: https://developer.mozilla.org/en-US/docs/Web/API/HTMLCanvasElement and the 2D context: https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D Link to comment Share on other sites More sharing options...
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