javascript 如何检测对 HTML5“下载”属性的支持？
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How to detect support for the HTML5 "download" attribute?
提问by Andrei Oniga
One of the new features implemented in HTML5 is the downloadattribute for anchor tags. The benefit of this attribute is that it gives users the means to download content created within a client application, such as an image (converted from a canvas, for instance).
HTML5 中实现的新功能之一是download锚标记的属性。此属性的好处在于，它为用户提供了下载在客户端应用程序中创建的内容的方法，例如图像（例如从画布转换而来）。
Currently, support for this feature is very poor, so I'd like to know how can I detect support for this feature in a browser.
目前，对这个功能的支持很差，所以我想知道如何在浏览器中检测对这个功能的支持。
回答by McGarnagle
回答by John
A single-line ifcondition to keep things simplified:
if使事情变得简单的单行条件：
if (document.createElement('a').download==undefined && e.target.hasAttribute('download'))
{
e.preventDefault();
console.log('Error: this is a download link, please right-click to save the file.');
}
Support for the downloadattribute is spotty (Chrome 14+, Firefox 20+, IE13+, Safari 10+ and no support in (real) Opera. The script above will not interfere with supported browsers.
对该download属性的支持参差不齐（Chrome 14+、Firefox 20+、IE13+、Safari 10+，在（真实）Opera 中不支持。上述脚本不会干扰支持的浏览器。
