日期:2014-05-17 浏览次数:20783 次
<!DOCTYPE html>
<html>
<body>
<canvas id="myCanvas" width="300" height="225">Your browser does not support the canvas tag.</canvas>
<canvas id="myCanvas1" width="500" height="375">Your browser does not support the canvas tag.</canvas>
<canvas id="myCanvas2" width="500" height="600">Your browser does not support the canvas tag.</canvas>
<canvas id="myCanvas3" width="1600" height="900">Your browser does not support the canvas tag.</canvas>
<img id="pic" src="./a.png" alt="beauty" width="400" height="300"/>
<script type="text/javascript">
var canvas=document.getElementById('myCanvas');
var ctx=canvas.getContext('2d');
ctx.fillStyle='#AA0000';
ctx.fillRect(100,100,100,100);//前两个是左上角相对浏览器的左上角的位置,后再从个参数是矩形的长宽。
function drawLine(){
			var canvas=document.getElementById('myCanvas1');
			var context=canvas.getContext('2d');
			context.fillStyle='#0AAA00';
			context.fillRect(50,25,180,80);//前两个是左上角相对浏览器的左上角的位置,后再从个参数是矩形的长宽。
			
			context.moveTo(50,100);
			context.lineTo(10,375);
			context.strokeStyle="#000";
			context.stroke();
			
			//下面4行语句,完成一线段的绘画
			context.moveTo(0,0); //起点?
			context.lineTo(500,23);//终点?
			context.strokeStyle="#000";//颜色方案
			context.stroke();//正式绘制
			
			context.font = "bold 50px sans-serif"; //从英文font看,是字体方案
			context.fillText("html5",250,43); //三个参数,第一个串表示要绘画的文字;第二,第三个表示水平,坚直座标。
			
			context.textAlign="right";
			context.textBaseLine="bottom";
			context.fillText("html5",250,190);
}
function drawGradients(){
	
		//渐变
	
		var canvas=document.getElementById('myCanvas2');
		var context=canvas.getContext('2d');
		
//		var my_gradient = context.createLinearGradient(0,0,100,10);
////		my_gradient.addColorStop(0,"black");
////		my_gradient.addColorStop(1,"white");
//		my_gradient.addColorStop(0,"red");
//		my_gradient.addColorStop(1,"blue");
//		context.fillStyle = my_gradient;
//		context.fillRect(0,0,300,255);
//		
	var my_gradient = context.createRadialGradient(0,0,30,50,50,50);
//		my_gradient.addColorStop(0,"black");
//		my_gradient.addColorStop(1,"white");
		my_gradient.addColorStop(0,"red");
		my_gradient.addColorStop(1,"blue");
		context.fillStyle = my_gradient;
		context.fillRect(0,0,300,255);
		
		
		
}
function drawImg(){
		var canvas=docum