有没有办法获得给定内容类型的扩展？

Question

Is there a way to do the inverse of this?

content type by extension

I have a WebResponse which has a content type and I need to cache the response with the appropriate extension.

image/png => .png

image/jpg => .jpg

Answer 1

Windows has a MIME-type database in the Registry. Internet Explorer uses this database to select the default extension for downloads in its Save As dialog.

The machine-level database is under HKEY_LOCAL_MACHINE\\SOFTWARE\\Classes\\MIME\\Database , with user-specific overrides under HKEY_CURRENT_USER\\Software\\Classes\\MIME\\DataBase . Windows merges these trees and exposes the result under HKEY_CLASSES_ROOT\\MIME\\DataBase .

The Content-Type mappings are in a tree located under the Content Type subkey; for example, the audio/mp3 type is located at:

HKEY_CLASSES_ROOT\MIME\Database\Content Type\audio/mp3

The default file extension, including the leading period character, is in the Extension named value.

Since another answer on StackOverflow already contains a snippet to do this I won't reinvent the wheel here :-)