常用的 MIME type

• MIME
  MIME(Multipurpose Internet Mail Extensions)多用途互联网邮件扩展类型。是设定某种扩展名的文件用一种应用程序来打开的方式类型，当该扩展名文件被访问的时候，浏览器会自动使用指定应用程序来打开。多用于指定一些客户端自定义的文件名，以及一些媒体文件打开方式。
  HTTP协议也使用了这个标准。当响应数据被发回到客户端浏览器的时候，响应头Content-Type应该告诉客户端：我发给你的数据是什么类型(以便客户浏览器对拿到的数据做解析)。

• 常用的MIME类型
  将mime_type和对应的响应头Content-Type的值的映射关系存储在一个JS对象中，调用即可：
  以下数据提取来源：https://developer.mozilla.org/zh-CN/docs/Web/HTTP/Basics_of_HTTP/MIME_types/Common_types

var mimeTypes = {
    ".aac": "audio/aac",	// AAC audio
    ".abw": "application/x-abiword",	// AbiWord document
    ".arc": "application/x-freearc",	// Archive document (multiple files embedded)
    ".avi": "video/x-msvideo",	// AVI: Audio Video Interleave
    ".azw": "application/vnd.amazon.ebook",	// Amazon Kindle eBook format
    ".bin": "application/octet-stream",	// Any kind of binary data
    ".bmp": "image/bmp",	// Windows OS/2 Bitmap Graphics
    ".bz": "application/x-bzip",	// BZip archive
    ".bz2": "application/x-bzip2",	// BZip2 archive
    ".csh": "application/x-csh",	// C-Shell script
    ".css": "text/css",	// Cascading Style Sheets (CSS)
    ".csv": "text/csv",	// Comma-separated values (CSV)
    ".doc": "application/msword",	// Microsoft Word
    ".docx": "application/vnd.openxmlformats-officedocument.wordprocessingml.document",	// Microsoft Word (OpenXML)
    ".eot": "application/vnd.ms-fontobject",	// MS Embedded OpenType fonts
    ".epub": "application/epub+zip",	// Electronic publication (EPUB)
    ".gif": "image/gif",	// Graphics Interchange Format (GIF)
    ".htm": "text/html", 
    ".html": "text/html",	// HyperText Markup Language (HTML)
    ".ico": "image/vnd.microsoft.icon",	// Icon format
    ".ics": "text/calendar",	// iCalendar format
    ".jar": "application/java-archive",	// Java Archive (JAR)
    ".jpeg": "image/jpeg",
    ".jpg": "image/jpeg",	// JPEG images
    ".js": "text/javascript",	// JavaScript
    ".json": "application/json",	// JSON format
    ".jsonld": "application/ld+json",	// JSON-LD format
    ".mid": "audio/midi audio/x-midi",
    ".midi": "audio/midi audio/x-midi",	// Musical Instrument Digital Interface (MIDI)
    ".mjs": "text/javascript",	// JavaScript module
    ".mp3": "audio/mpeg",	// MP3 audio
    ".mpeg": "video/mpeg",	// MPEG Video
    ".mpkg": "application/vnd.apple.installer+xml",	// Apple Installer Package
    ".odp": "application/vnd.oasis.opendocument.presentation",	// OpenDocument presentation document
    ".ods": "application/vnd.oasis.opendocument.spreadsheet",	// OpenDocument spreadsheet document
    ".odt": "application/vnd.oasis.opendocument.text",	// OpenDocument text document
    ".oga": "audio/ogg",	// OGG audio
    ".ogv": "video/ogg",	// OGG video
    ".ogx": "application/ogg",	// OGG
    ".otf": "font/otf",	// OpenType font
    ".png": "image/png",	// Portable Network Graphics
    ".pdf": "application/pdf",	// Adobe Portable Document Format (PDF)
    ".ppt": "application/vnd.ms-powerpoint",	// Microsoft PowerPoint
    ".pptx": "application/vnd.openxmlformats-officedocument.presentationml.presentation",	// Microsoft PowerPoint (OpenXML)
    ".rar": "application/x-rar-compressed",	// RAR archive
    ".rtf": "application/rtf",	// Rich Text Format (RTF)
    ".sh": "application/x-sh",	// Bourne shell script
    ".svg": "image/svg+xml",	// Scalable Vector Graphics (SVG)
    ".swf": "application/x-shockwave-flash",	// Small web format (SWF) or Adobe Flash document
    ".tar": "application/x-tar",	// Tape Archive (TAR)
    ".tif": "image/tiff",
    ".tiff": "image/tiff",	// Tagged Image File Format (TIFF)
    ".ttf": "font/ttf",	// TrueType Font
    ".txt": "text/plain",	// Text, (generally ASCII or ISO 8859-n)
    ".vsd": "application/vnd.visio",	// Microsoft Visio
    ".wav": "audio/wav",	// Waveform Audio Format
    ".weba": "audio/webm",	// WEBM audio
    ".webm": "video/webm",	// WEBM video
    ".webp": "image/webp",	// WEBP image
    ".woff": "font/woff",	// Web Open Font Format (WOFF)
    ".woff2": "font/woff2",	// Web Open Font Format (WOFF)
    ".xhtml": "application/xhtml+xml",	// XHTML
    ".xls": "application/vnd.ms-excel",	// Microsoft Excel
    ".xlsx": "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",	// Microsoft Excel (OpenXML)
    ".xml": "application/xml",  //  代码对普通用户来说不可读 (RFC 3023, section 3)
    ".xml": "text/xml",	// XML 代码对普通用户来说可读 (RFC 3023, section 3)
    ".xul": "application/vnd.mozilla.xul+xml",	// XUL
    ".zip": "application/zip",	// ZIP archive
    ".3gp": "video/3gpp",       // 含视频
    // ".3gp": "audio/3gpp",	// 3GPP audio/video container（若不含视频）
    ".3g2": "video/3gpp2",      // 含视频
    // ".3g2": "audio/3gpp2",	// 3GPP2 audio/video container（若不含视频）
    ".7z": "application/x-7z-compressed",	// 7-zip archive
};