html5 Methods to clear canvas: 1. Use the "clearCanvas" method to clear the canvas; 2. Use the clearRect method to clear the canvas; 3. Fill the canvas with a specific color to clear the canvas.
The operating environment of this article: Windows7 system, HTML5&&CSS3 version, DELL G3 computer
html5 canvas clear canvas method
Summary as follows Three ways to clear the canvas:
1. The simplest method: Since the canvas content will be cleared whenever the height or width of the canvas is reset, you can use the following methods to clear it:
function clearCanvas() { var c=document.getElementById("myCanvas"); var cxt=c.getContext("2d"); c.height=c.height; }
2. Use the clearRect method:
function clearCanvas() { var cxt=document.getElementById("myCanvas").getContext("2d"); cxt.clearRect(0,0,c.width,c.height); }
3. Similar to method 2, you can fill the canvas with a specific color to achieve the purpose of clearing it:
function clearCanvas() { var c=document.getElementById("myCanvas"); var cxt=c.getContext("2d"); cxt.fillStyle="#000000"; cxt.beginPath(); cxt.fillRect(0,0,c.width,c.height); cxt.closePath(); }
Recommended learning: " HTML video tutorial》
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