子循

1.鼠标绘图 无标题文档 body{ background:black;} #c1{ background:white;} span{ color:white;} window.onload = function(){ var oC = document.getElementById('c1'); var oGC = oC.getContext('2d');

1.时钟 window.onload = function(){ var oC = document.getElementById('c1'); var oGC = oC.getContext('2d'); function toDraw(){ var x = 200; var y = 200; var r = 150; oGC.clearRect(0,

1.插入图片             等图片加载完，再执行canvas操作  -图片预加载：在onload中调用             drawImage(olmg,x,y,w,h) -olmg:当前图片x,y：坐标w,h：宽高 简单例子： 无标题文档 body{ background:black;} #c1{ background:white;} w

1.清除一个特定区域内的Canvas context.fillRect(40, 40, 100, 100); context.beginPath(); context.arc(230, 90, 50, 0, Math.PI*2, false); context.closePath(); context.fill(); context.clearRect(230, 90, 50, 50);