解决各大浏览器下载文件名显示不正确的情况

下载时，最关键的三步：

response.reset();//清空缓存区，防止存在某些字符使得下载的文件格式错误
response.setContentType("application/pdf;charset=UTF-8");//指定文件类型，其他类型可参见w3school的文档，也可参见下文的附录标准
response.setHeader("Content-Disposition", "attachment;filename=temp.pdf");// attachment后面一定是逗号，这个地方我就犯过错误，写成了:，结果死活不对

解决下载时，中文文件名显示不正确的方法：

理论依据：

浏览器能正确识别的编码格式，只要按照这样的编码来设置对应的Content-Disposition，那么应该就不会出现中文文件名的乱码问题了。
首先，Content-Disposition值可以有以下几种编码格式
1. 直接urlencode：
Content-Disposition: attachment; filename="struts2.0%E4%B8%AD%E6%96%87%E6%95%99%E7%A8%8B.chm"
2. Base64编码：
Content-Disposition: attachment; filename="=?UTF8?B?c3RydXRzMi4w5Lit5paH5pWZ56iLLmNobQ==?="
3. RFC2231规定的标准：
Content-Disposition: attachment; filename*=UTF-8''%E5%9B%9E%E6%89%A7.msg
4. 直接ISO编码的文件名：
Content-Disposition: attachment;filename="测试.txt"
然后，各浏览器支持的对应编码格式为：
1. IE浏览器，采用URLEncoder编码
2. Opera浏览器，采用filename*方式
3. Safari浏览器，采用ISO编码的中文输出
4. Chrome浏览器，采用Base64编码或ISO编码的中文输出
5. FireFox浏览器，采用Base64或filename*或ISO编码的中文输出

源代码：

private String getDownLoadFileName(String filename) {
		String new_filename = null;
		try {
			new_filename = URLEncoder.encode(filename, "UTF8");
		} catch (UnsupportedEncodingException e1) {
			e1.printStackTrace();
		}
		HttpServletRequest request = ServletActionContext.getRequest();
		String userAgent = request.getHeader("User-Agent");
		// System.out.println(userAgent);
		String rtn = "filename=\"" + new_filename + "\"";
		// 如果没有UA，则默认使用IE的方式进行编码，因为毕竟IE还是占多数的
		if (userAgent != null) {
			userAgent = userAgent.toLowerCase();
			// IE浏览器，只能采用URLEncoder编码
			if (userAgent.indexOf("msie") != -1) {
				rtn = "filename=\"" + new_filename + "\"";
			}
			// Opera浏览器只能采用filename*
			else if (userAgent.indexOf("opera") != -1) {
				rtn = "filename*=UTF-8''" + new_filename;
			}
			// Safari浏览器，只能采用ISO编码的中文输出
			else if (userAgent.indexOf("safari") != -1) {
				try {
					rtn = "filename=\""
							+ new String(filename.getBytes("UTF-8"),
									"ISO8859-1") + "\"";
				} catch (UnsupportedEncodingException e) {
					e.printStackTrace();
				}
			}
			// Chrome浏览器，只能采用MimeUtility编码或ISO编码的中文输出
			else if (userAgent.indexOf("applewebkit") != -1) {
				try {
					new_filename = MimeUtility
							.encodeText(filename, "UTF8", "B");
				} catch (UnsupportedEncodingException e) {
					e.printStackTrace();
				}
				rtn = "filename=\"" + new_filename + "\"";
			}
			// FireFox浏览器，可以使用MimeUtility或filename*或ISO编码的中文输出
			else if (userAgent.indexOf("mozilla") != -1) {
				rtn = "filename*=UTF-8''" + new_filename;
			}
		}
		return rtn;
	}

基本能解决大部分浏览器中文显示不正常的情况，但是，浏览器还有版本的，所以最好的方式就是能不用中文的时候，尽量别用中文

附录：

按照文件扩展名排列的 Mime 类型列表

扩展名 类型/子类型

	application/octet-stream
323	text/h323
acx	application/internet-property-stream
ai	application/postscript
aif	audio/x-aiff
aifc	audio/x-aiff
aiff	audio/x-aiff
asf	video/x-ms-asf
asr	video/x-ms-asf
asx	video/x-ms-asf
au	audio/basic
avi	video/x-msvideo
axs	application/olescript
bas	text/plain
bcpio	application/x-bcpio
bin	application/octet-stream
bmp	image/bmp
c	text/plain
cat	application/vnd.ms-pkiseccat
cdf	application/x-cdf
cer	application/x-x509-ca-cert
class	application/octet-stream
clp	application/x-msclip
cmx	image/x-cmx
cod	image/cis-cod
cpio	application/x-cpio
crd	application/x-mscardfile
crl	application/pkix-crl
crt	application/x-x509-ca-cert
csh	application/x-csh
css	text/css
dcr	application/x-director
der	application/x-x509-ca-cert
dir	application/x-director
dll	application/x-msdownload
dms	application/octet-stream
doc	application/msword
dot	application/msword
dvi	application/x-dvi
dxr	application/x-director
eps	application/postscript
etx	text/x-setext
evy	application/envoy
exe	application/octet-stream
fif	application/fractals
flr	x-world/x-vrml
gif	image/gif
gtar	application/x-gtar
gz	application/x-gzip
h	text/plain
hdf	application/x-hdf
hlp	application/winhlp
hqx	application/mac-binhex40
hta	application/hta
htc	text/x-component
htm	text/html
html	text/html
htt	text/webviewhtml
ico	image/x-icon
ief	image/ief
iii	application/x-iphone
ins	application/x-internet-signup
isp	application/x-internet-signup
jfif	image/pipeg
jpe	image/jpeg
jpeg	image/jpeg
jpg	image/jpeg
js	application/x-javascript
latex	application/x-latex
lha	application/octet-stream
lsf	video/x-la-asf
lsx	video/x-la-asf
lzh	application/octet-stream
m13	application/x-msmediaview
m14	application/x-msmediaview
m3u	audio/x-mpegurl
man	application/x-troff-man
mdb	application/x-msaccess
me	application/x-troff-me
mht	message/rfc822
mhtml	message/rfc822
mid	audio/mid
mny	application/x-msmoney
mov	video/quicktime
movie	video/x-sgi-movie
mp2	video/mpeg
mp3	audio/mpeg
mpa	video/mpeg
mpe	video/mpeg
mpeg	video/mpeg
mpg	video/mpeg
mpp	application/vnd.ms-project
mpv2	video/mpeg
ms	application/x-troff-ms
mvb	application/x-msmediaview
nws	message/rfc822
oda	application/oda
p10	application/pkcs10
p12	application/x-pkcs12
p7b	application/x-pkcs7-certificates
p7c	application/x-pkcs7-mime
p7m	application/x-pkcs7-mime
p7r	application/x-pkcs7-certreqresp
p7s	application/x-pkcs7-signature
pbm	image/x-portable-bitmap
pdf	application/pdf
pfx	application/x-pkcs12
pgm	image/x-portable-graymap
pko	application/ynd.ms-pkipko
pma	application/x-perfmon
pmc	application/x-perfmon
pml	application/x-perfmon
pmr	application/x-perfmon
pmw	application/x-perfmon
pnm	image/x-portable-anymap
pot,	application/vnd.ms-powerpoint
ppm	image/x-portable-pixmap
pps	application/vnd.ms-powerpoint
ppt	application/vnd.ms-powerpoint
prf	application/pics-rules
ps	application/postscript
pub	application/x-mspublisher
qt	video/quicktime
ra	audio/x-pn-realaudio
ram	audio/x-pn-realaudio
ras	image/x-cmu-raster
rgb	image/x-rgb
rmi	audio/mid
roff	application/x-troff
rtf	application/rtf
rtx	text/richtext
scd	application/x-msschedule
sct	text/scriptlet
setpay	application/set-payment-initiation
setreg	application/set-registration-initiation
sh	application/x-sh
shar	application/x-shar
sit	application/x-stuffit
snd	audio/basic
spc	application/x-pkcs7-certificates
spl	application/futuresplash
src	application/x-wais-source
sst	application/vnd.ms-pkicertstore
stl	application/vnd.ms-pkistl
stm	text/html
svg	image/svg+xml
sv4cpio	application/x-sv4cpio
sv4crc	application/x-sv4crc
swf	application/x-shockwave-flash
t	application/x-troff
tar	application/x-tar
tcl	application/x-tcl
tex	application/x-tex
texi	application/x-texinfo
texinfo	application/x-texinfo
tgz	application/x-compressed
tif	image/tiff
tiff	image/tiff
tr	application/x-troff
trm	application/x-msterminal
tsv	text/tab-separated-values
txt	text/plain
uls	text/iuls
ustar	application/x-ustar
vcf	text/x-vcard
vrml	x-world/x-vrml
wav	audio/x-wav
wcm	application/vnd.ms-works
wdb	application/vnd.ms-works
wks	application/vnd.ms-works
wmf	application/x-msmetafile
wps	application/vnd.ms-works
wri	application/x-mswrite
wrl	x-world/x-vrml
wrz	x-world/x-vrml
xaf	x-world/x-vrml
xbm	image/x-xbitmap
xla	application/vnd.ms-excel
xlc	application/vnd.ms-excel
xlm	application/vnd.ms-excel
xls	application/vnd.ms-excel
xlt	application/vnd.ms-excel
xlw	application/vnd.ms-excel
xof	x-world/x-vrml
xpm	image/x-xpixmap
xwd	image/x-xwindowdump
z	application/x-compress
zip	application/zip