1 var canvas = document.getElementById("myCanvas"); 2 if(canvas.getContext == null){ 3 return false; 4 } 5 var context = canvas.getContext("2d"); 6 context.shadowBlur = 20; 7 context.shadowColor = "rgb(0,0,0)"; 8 context.fillRect(150,150,100,100); 9 10 context.shadowBlur = 0; 11 context.shadowOffsetX = 10; 12 context.shadowOffsetY = 10; 13 context.shadowColor = "rgba(100, 100, 100, 0.5)"; 14 context.fillRect(200,50,100,100); 15 16 context.shadowColor = "rgb(255,0,0)"; 17 context.shadowBlur = 50; 18 context.shadowOffsetX = 0; 19 context.shadowOffsetY = 0; 20 context.beginPath(); 21 context.arc(400,100,50,0,Math.PI*2,false); 22 context.closePath(); 23 context.fill();
shadowBlur shadowOffsetX shadowOffsetY shadowColor 四个选项