線性漸變:ctx.createLinearGradient(x1,y1,x2,y2);
<script type="text/javascript">
//1.線性漸變:lineargradient=ctx.createLinearGradient(x1,y1,x2,y2); x1,y1為線性漸變的起點,x2,y2為線性漸變的終點
// lineargradient.addColorStop(position,color); //定義色标的位置并上色
function draw(){
var ctx=document.getElementById("myCanvas").getContext('2d');
var lingrad=ctx.createLinearGradient(0,0,0,200);
lingrad.addColorStop(1/7,'#ff9900');
lingrad.addColorStop(2/7,'#ffff00');
lingrad.addColorStop(3/7,'#00ff00');
lingrad.addColorStop(4/7,'#00ffff');
lingrad.addColorStop(5/7,"#0000ff");
lingrad.addColorStop(6/7,'#ff00ff');
lingrad.addColorStop(7/7,'#ff0000');
ctx.fillStyle=lingrad;
ctx.strokeStyle=lingrad;
ctx.fillRect(10,10,200,200);
}
window.οnlοad=function(){
draw();
}
</script>
<canvas id="myCanvas" width="300" height="240"></canvas>
徑向漸變:ctx.createRadialGradient(x1,y1,r1,x2,y2,r2)
<script type="text/javascript">
//1.徑向漸變:radialgradient=ctx.createRadialGradient(x1,y1,r1,x2,y2,r2); x1,y1為圓心,r1為半徑,x2,y2為圓心,r2為半徑
// radialgradient.addColorStop(position,color); //定義色标的位置并上色
function draw(){
var ctx=document.getElementById("myCanvas").getContext('2d');
var radgrad=ctx.createRadialGradient(55,55,20,100,100,90);
radgrad.addColorStop(0,'#ffffff');
radgrad.addColorStop(0.75,'#333333');
radgrad.addColorStop(1,'#000000');
ctx.fillStyle=radgrad;
ctx.fillRect(10,10,200,200);
}
window.οnlοad=function(){
draw();
}
</script>
<canvas id="myCanvas" width="300" height="240"></canvas>