application/xml and text/xml的区别

经常看到有关xml时提到"application/xml" 和 "text/xml"两种类型， 二者功能一模一样，唯一的区别就是编码格式，text/xml忽略xml头所指定编码格式而默认采用us-ascii编码，而application/xml会根据xml头指定的编码格式来编码：

     XML has two MIME types,application/xml and text/xml . These are often used interchangeably, but there is a subtle difference which is why application/xml is generally recommended over the latter.

     Let me explain why: according to the standard, text/* -MIME types have a us-ascii character set unless otherwise specified in the HTTP headers. This effectively means that any encoding defined in the XML prolog (e.g. <?xml version=”1.0” encoding=”UTF-8”?>) is ignored. This is of course not the expected and desired behaviour.    

     To further complicate matters, most/all browser implementations actually implement nonstandard behaviour for text/xml because they process the encoding as if it were application/xml .    

     So, text/* has encoding issues, and is not implemented by browsers in a standards-compliant manner, which is why using application/* is recommended.

http://www.ietf.org/rfc/rfc2376.txt