当内容类型标头为 image/jpeg 时，HTTP 响应的内容数据格式是什么？

Question

只是好奇，当内容类型标头为 image/jpeg、二进制时，HTTP 响应正文的内容数据类型格式是什么？通过 Mozilla Firebug 查看时无法看到 HTTP 响应的原始内容，因为它已经随图像一起弹出。

我从来没有想过太多这个问题，直到与一个人交谈，他告诉我他将二进制数据编码为 Base64 格式数据到 HTTP 响应正文中。当我们需要这样做时，有什么用例吗？

Answer 1

这就是您得到的响应标头。它还包括内容类型：image/jpeg

HTTP/1.1 200 OK 
Last-Modified: Fri, 10 Feb 2012 14:31:06 GMT
Content-Type: image/jpeg
Content-Length: 20331
Server: WEBrick/1.3.1 (Ruby/1.9.2/2011-02-18)
Date: Fri, 10 Feb 2012 14:31:22 GMT
Connection: Keep-Alive

，原始内容数据为：

......JFIF.............0Photo: Osvaldo Gago
http://www.fotografar.net....Photoshop 3.0.8BIM.......x............beach.....Algarve.....Faro..n..Osvaldo Gago..t.*Creative Commons Atribuition + Share Alike..z..Osvaldo Gago.8BIM........fotografar.net..1.Exif..II*................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................h..............................."...........................$...........,...........d....... ...l............................... .................).............
..."...........\...................................... .......... .C................... 

...................."...........D.....f...*...........................*.....(............................................... 
.. 
....'.................................................IMG:PowerShot G5 JPEG...........Firmware Version 1.00...................................
.........D...%.................@...........