概述
WindowOrWorkerGlobalScope.atob() 对用base-64编码过的字符串进行解码 。你可以使用 window.btoa() 方法来编码一个可能在传输过程中出现问题的数据，并且在接受数据之后，使用 atob() 方法再将数据解码。例如：你可以编码、传输和解码操作各种字符，比如0-31的ASCII码值。
关于针对Unicode或者UTF-8的应用方面，请查看 this note at Base64 encoding and decoding 和 this note at window.btoa()。
语法
let decodedData = window.atob(encodedData);
例子
let encodedData = window.btoa("Hello, world"); // 编码
let decodedData = window.atob(encodedData); // 解码
规范
| Specification | Status | Comment |
|---|---|---|
| HTML Living Standard WindowBase64.atob() |
Living Standard | No change since the latest snapshot, HTML 5.1. |
| HTML 5.1 WindowBase64.atob() |
Recommendation | Snapshot of HTML Living Standard. No change. |
| HTML5 WindowBase64.atob() |
Recommendation | Snapshot of HTML Living Standard. Creation of WindowBase64 (properties were on the target before it). |
浏览器兼容性
We're converting our compatibility data into a machine-readable JSON format. This compatibility table still uses the old format, because we haven't yet converted the data it contains. Find out how you can help!
| Feature | Chrome | Firefox (Gecko) | Internet Explorer | Opera | Safari (WebKit) |
|---|---|---|---|---|---|
| Basic support | (Yes) | 1.0 (1.7 or earlier)[1] 27 (27)[2] |
10 | (Yes) | (Yes) |
| Feature | Android | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
|---|---|---|---|---|---|
| Basic support | (Yes) | 1.0 (1) | 未实现 | ? | (Yes) |
[1] atob() 也适用于用JavaScript实现的XPCOM组件，尽管在组件里面 window 不再是全局对象。
[2] 从 Firefox 27 开始, 遵从最新的HTML5 spec，atob() 会忽略所有的空白字符。 (bug 711180)
相关链接