XML文件中的UTF-8与UTF8

Question

XML文件中的正确UTF8编码声明是什么？我见过两者.

<?xml version="1.0" encoding="UTF-8"?>
...

要么

<?xml version="1.0" encoding="UTF8"?>
...

Answer 1

XML规范(https://www.w3.org/TR/REC-xml/#charencoding)说:

在编码声明中,值"UTF-8","UTF-16","ISO-10646-UCS-2"和"ISO-10646-UCS-4"应该用于Unicode的各种编码和转换/ ISO/IEC 10646 ......

此外,"编码"的值可以是来自IANA-CHARSETS(http://www.iana.org/assignments/character-sets/character-sets.xhtml)的任何值.

UTF-8定义为"UTF-8"或别名"csUTF8"

因此,它应该是"UTF-8"