问题：
Is it possible to capture or print what's displayed in an html canvas as an image or pdf? 是否能够捕获或打印html画布中显示为图像或pdf的内容？ html
I'd like to generate an image via canvas, and be able to generate a png from that image. 我想经过画布生成图像，并可以从该图像生成png。 canvas
解决方案：
参考一： https://stackoom.com/question/3sLN/将HTML-Canvas捕获为gif-jpg-png-pdf吗参考二： https://oldbug.net/q/3sLN/Capture-HTML-Canvas-as-gif-jpg-png-pdf