FileReader：error 属性
Baseline Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
备注： 此特性在 Web Worker 中可用。
FileReader 接口的 error 只读属性返回读取文件时发生的错误。
值
包含相关错误的 DOMException 对象。
规范
| Specification |
|---|
| File API # dom-filereader-error |