JSPDF 原理

Jspdf是一个将html内容生成pdf文件的库，原理是对输入浏览器的文字或二进制图片进行base64编码转换，以pdf中应有的形式组织，最终以data uri scheme,

data:application/pdf;base64;[content] 的格式输出

里面的save方法是如何做到浏览器端保存文件的呢?

看下这个:

<a href="data:image/gif;base64,iVBORw0KGgoAAAANSUhEUgAAAHsAAAAyCAIAAADz8jOMAAAAmklEQVR42u3QQQoAIQgAQP//aRc2NsQ8xJ7HQ2hkykS8kZnrXMm+3GV+Ue9r0lqyxFmOE9vLlo9za+P9kq1rzMe590uOH8Y5njhx4sSJEydOnDhx4sSJEydOnDhx4sSJEydOnDhx4sSJEydOnDhx4sSJEydOnDhx4sSJEydOnDhx4sSJEydOnDhx4sSJEydOnDhx4sSJE/8t/gBbNfIWdjsEtgAAAABJRU5ErkJggg==" download="文件名">A标签</a>

 

通过给href属性添加data uri scheme，给download属性添加文件名称，点击时就能下载。