In canvas, when writing width and height on canvas, it is the actual artboard size of canvas. By default, width is 300px and height is 150px.
When writing css style in style, widht and height are the actual display size.
Now use canvas to draw a diagonal line as an example:
canvas</title> ; <br /><script type='text/javascript'> <br>window.onload = function(){ <br>getCanvas(); <br>}; <br>//canvase drawing<br>function getCanvas(){ <br>//Get the canvas element and its drawing context <br>var canvas = document.getElementById('canvasId'); <br>var context = canvas.getContext('2d'); <br>/ /Use absolute landmarks to create a path <br>context.beginPath(); <br>context.moveTo(0,200); <br>context.lineTo(200,0); <br>//Draw this first to On canvas <br>context.stroke(); <br>} <br></script> <br></head> <br><body> <br><canvas id='canvasId' width ="200px" height='200px' style='width:400px;height:200px;' ></canvas> <br></body> <br></html> <br>
</div> <br>The display effect is as follows: <br><img src="http://files.jb51.net/file_images/article/201301/201316172320955.png" alt=""> <br>As you can see, the canvas drawing board is a square of 200*200, and the drawing uses the diagonal display from (0, 200) to (200, 0). <br>But the graph is displayed as a 400*200 rectangle, and it also displays diagonals.</div><div class="nphpQianMsg"><div class="clear"></div></div><div class="nphpQianSheng"><span>Statement：</span><div>The content of this article is voluntarily contributed by netizens, and the copyright belongs to the original author. This site does not assume corresponding legal responsibility. If you find any content suspected of plagiarism or infringement, please contact admin@php.cn</div></div></div><div class="nphpSytBox"><span>Previous article：<a class="dBlack" title="Implementation of new tags using HTML5 in old browsers such as IE6 series_html5 tutorial tips" href="https://m.php.cn/faq/6515.html">Implementation of new tags using HTML5 in old browsers such as IE6 series_html5 tutorial tips</a></span><span>Next article：<a class="dBlack" title="Implementation of new tags using HTML5 in old browsers such as IE6 series_html5 tutorial tips" href="https://m.php.cn/faq/6519.html">Implementation of new tags using HTML5 in old browsers such as IE6 series_html5 tutorial tips</a></span></div><div class="nphpSytBox2"><div class="nphpZbktTitle"><h2>Related articles</h2><em><a href="https://m.php.cn/article.html" class="bBlack"><i>See more</i><b></b></a></em><div class="clear"></div></div><ins class="adsbygoogle"
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