小编Sup*_*iji的帖子

使用rabbitmq,我们可以安装管理插件.然后我们http://localhost:55672/使用guest:guest 访问浏览器.问题是,我不能再登录,因为我更改了密码并为角色输入了空白.

有没有办法重置用户的rabbitmq管理？

我知道我可以使用 javascript 做到这一点：

var ctx = getCanvas('testCanvas').getContext('2d'); // get Canvas context
var img = new Image();
img.src = 'test.png';
img.onload = function(){
    ctx.drawImage(img, 200, 200); // x, y, width, height
}

但是如何将现有标签绘制到画布上：

在 HTML 中：

<img src='test.png'>

为什么我要这样做？我想使用 pagespeed 优化图像加载

假设我有这个 html：

<style>
    p { text-align: justify; margin:0; }
</style>

<p>This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. Last line
<p>This is a paragraph. This is a paragraph. This is a paragraph. This is a paragraph. …