<!DOCTYPE html>
<!-- to moving elements in a straight line -->
<html>
<head>
<meta charset='utf-8'/>
<script type="text/javascript">
window.addEventListener('load',canvasApp, false);
function canvasApp(args) {
var canvas = document.getElementById("MyCanvas");
var context = canvas.getContext("2d");
var logoL = new Image();
logoL.src= "../img/csrLeft.png";
var widthL = 88;
var logoR = new Image();
logoR.src = "../img/csrRight.png";
var widthR = 286;
var height = 31;
context.drawImage(logoL,0,0);
var dataL = context.getImageData(0,0,widthL,height);
for (var i=0; i<dataL.data.length; i+=4 ) {
dataL.data[i] = 29;
dataL.data[i+1] = 58;
dataL.data[i+2] = 87;
}
context.putImageData(dataL,0,0);
}
</script>
</head>
<body>
<div style="position: absolute; top: 50px; left: 50px; ">
<canvas id="MyCanvas" width="500" height="500">
Your brower doesn't support canvas
</canvas>
</div>
</body>
</html> firebug提示var dataL = context.getImageData(0,0,widthL,height);这行代码不安全 颜色也没有改变~ 不知道为什么????Canvas
<!-- to moving elements in a straight line -->
<html>
<head>
<meta charset='utf-8'/>
<script type="text/javascript">
window.addEventListener('load',canvasApp, false);
function canvasApp(args) {
var canvas = document.getElementById("MyCanvas");
var context = canvas.getContext("2d");
var logoL = new Image();
logoL.src= "../img/csrLeft.png";
var widthL = 88;
var logoR = new Image();
logoR.src = "../img/csrRight.png";
var widthR = 286;
var height = 31;
context.drawImage(logoL,0,0);
var dataL = context.getImageData(0,0,widthL,height);
for (var i=0; i<dataL.data.length; i+=4 ) {
dataL.data[i] = 29;
dataL.data[i+1] = 58;
dataL.data[i+2] = 87;
}
context.putImageData(dataL,0,0);
}
</script>
</head>
<body>
<div style="position: absolute; top: 50px; left: 50px; ">
<canvas id="MyCanvas" width="500" height="500">
Your brower doesn't support canvas
</canvas>
</div>
</body>
</html> firebug提示var dataL = context.getImageData(0,0,widthL,height);这行代码不安全 颜色也没有改变~ 不知道为什么????Canvas
如果一定要测试这个代码,解决办法也容易,我是直接把文件放到了apache根目录或者iis中,然后localhost访问就OK了。。
http://hi.baidu.com/jmtbai/item/718fdcf9622f9329743c4c91