我想将Base64编码的PNG图像加载到canvas元素.我有这个代码:
<html>
<head>
</head>
<body>
<canvas id="c"></canvas>
<script type="text/javascript">
var canvas = document.getElementById("c");
var ctx = canvas.getContext("2d");
data = "data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUAAAAFCAIAAAACDbGyAAAAAXNSR0IArs4c6QAAAAlwSFlzAAALEwAACxMBAJqcGAAAAAd0SU1FB9oMCRUiMrIBQVkAAAAZdEVYdENvbW1lbnQAQ3JlYXRlZCB3aXRoIEdJTVBXgQ4XAAAADElEQVQI12NgoC4AAABQAAEiE+h1AAAAAElFTkSuQmCC";
ctx.drawImage(data, 0, 0);
</script>
</body>
</html>
在Chrome 8中,我收到错误消息: Uncaught TypeError: Type error
在Firefox的Firebug中:"对象的类型与对象关联的参数的预期类型不兼容"代码:"17"
在那个base64中是我在GIMP中制作的5x5px黑色PNG方块,并在GNU/Linux程序base64中将其转换为base64.
我正在开发一个Chrome/Chromium扩展程序,它将从学校系统中读取成绩等级的学校成绩.问题是该网站不记得登录用户.因此,我不能使用AJAX.
只有当我在其他标签上登录该页面时.但我想在后台自动登录该页面.解决方案可能是iframe标签,但Chrome/Chromium不允许我使用iframe内容进行阅读和操作.是否有任何解决方案如何作为登录用户在页面中操作？谢谢
google-chrome xmlhttprequest cross-domain google-chrome-extension
我有这个代码,在Firefox中运行良好,但在Chrome中我发现此错误:
sprites.js中的"未捕获错误:INVALID_STATE_ERR:DOM异常11":36
在这一行是这段代码:
context.drawImage(
Context是一个全局变量,其中包含canvas的2d上下文.这是完整的代码:
的index.html
<!doctype html>
<html>
<head>
<meta charset="UTF-8">
<script type="text/javascript" src="sprites.js"></script>
<script type="text/javascript" src="game.js"></script>
<script type="text/javascript" src="prototypes.js"></script>
<script type="text/javascript" src="initialize.js"></script>
</head>
<body onload="initialize()">
</body>
</html>
sprites.js
function SpritePrototype(frames, width, height, type)
{
this.frames = frames;
this.type = type;
if (this.frames > 0) {
this.frameArray = new Array(this.frames);
for (var i = 0; i < this.frames; i++) {
this.frameArray[i] = document.createElement("canvas");
}
}
}
function Sprite()
{
this.id = 0;
this.prototype = 0;
this.next = 0;
this.prev …