Let’s start with something simple
fillRect(x,y,width,height)
Add a width and height at the coordinates x and y, such as:
fillRect(0,0,500,500)//在坐标0,0处加上一个宽高500的填充矩形
strokeRect(x,y,width,height)
Add a wide and high border rectangle at the coordinates x, y position
but you need to use lineWidth, lineJoin, strokeStyle, miterLimit settings The rectangular function will be given below
clearRect(x,y,width,height)
Clear the position width and height of the coordinates x and y, and the area will be completely transparent
It feels a bit like using a black layer in PS, pulling a rectangular selection box, and then pressing deselect to make it transparent
Then set the fill style
context.fillStyle='#000000' //填充颜色context.strokeStyle='#ff00ff' //边框颜色
Full code
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><meta http-equiv="Content-Type" content="text/html; charset=utf-8" /><title>矩形</title><script src="js/modernizr.js"></script></head><body><script type="text/javascript">window.addEventListener('load',eventWindowLoaded,false);function eventWindowLoaded(){ canvasApp();}function canvasSupport(){ return Modernizr.canvas;}function canvasApp(){ if(!canvasSupport()){ return; }else{ var theCanvas = document.getElementById('canvas') var context = theCanvas.getContext("2d") } drawScreen(); function drawScreen(){ context.fillStyle="#000000"; //填充黑色 context.strokeStyle='#ff00ff' //边框为粉色 context.lineWidth=2; //边框宽度 context.fillRect(10,10,40,40) //矩形 context.strokeRect(0,0,60,60) //边框出现的位置 context.clearRect(20,20,20,20) //清除区域的位置} }</script><canvas id="canvas" width="500" height="500">你的浏览器无法使用canvas如有疑问加QQ:1035417613;小白童鞋;你的支持是我最大的快乐!!</canvas></body></html>
The result is this
If you don’t understand the previous structure, you can read my previous article http://www.cnblogs.com/LoveOrHate/p/4388321.html