问题
My web server serves content that is in 95% of the time just simple ascii. However in some rare cases, the content contains some German non-ascii characters.
Now I could set the content-type response header by detecting if the content contains any non-ascii characters, or I could just always set the response header:
Content-Type: text/plain; charset=UTF-8
Is there any disadvantage in doing the latter?
回答1:
Nope, all it's there for is to tell the browser which character set to decode your response with.
回答2:
ASCII is a subset of UTF-8, so it is perfectly safe to declare the charset as utf-8 for an all-ASCII document.
回答3:
No, there is no disadvantage -- but you'll need to spell "utf-8" correctly.
来源：https://stackoverflow.com/questions/17934505/is-there-any-disadvantage-of-using-text-plain-charset-utf-8