new TextDecoder([encoding[, options]])
创建新的 TextDecoder 实例。
encoding 可以指定支持的编码之一或别名。
TextDecoder 类也在全局对象上可用。
- encoding<string> Identifies the- encodingthat this- TextDecoderinstance supports. Default:- 'utf-8'.
- options<Object>- fatal<boolean>- trueif decoding failures are fatal. This option is not supported when ICU is disabled (see Internationalization). Default:- false.
- ignoreBOM<boolean> When- true, the- TextDecoderwill include the byte order mark in the decoded result. When- false, the byte order mark will be removed from the output. This option is only used when- encodingis- 'utf-8',- 'utf-16be'or- 'utf-16le'. Default:- false.
 
Creates an new TextDecoder instance. The encoding may specify one of the
supported encodings or an alias.
The TextDecoder class is also available on the global object.