本文就单文件上传和批量文件上传来进行讲解
具体示例
首页上传页面
Html代码
<span style="font-size: large;"><span style="font-size: large;"><%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ taglib uri="/struts-tags" prefix="s" %>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>Struts2文件上传示例</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<h3>Struts2文件上传示例</h3><hr/>
<form action="fileUpload.action" method="post" enctype="multipart/form-data">
<input type="file" name="up" style="width: 500px"/> <s:fielderror name="up"></s:fielderror><br/>
<input type="submit" value="开始上传"/>
<s:token/>
</form>
<h3>Struts2批量文件上传示例</h3><hr/>
<form action="batchFileUpload.action" method="post" enctype="multipart/form-data">
<s:fielderror name="up"></s:fielderror><br/>
<input type="file" name="up" style="width: 500px"/> <br/>
<input type="file" name="up" style="width: 500px"/><br/>
<input type="file" name="up" style="width: 500px"/> <br/>
<input type="submit" value="开始上传"/>
<s:token/>
</form>
</body>
</html></span></span>
单文件上传的Action
Java代码
<span style="font-size: large;"><span style="font-size: large;">package com.javacrazyer.action;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
public class FileUploadAction extends ActionSupport {
private static final long serialVersionUID = -7001482935770262132L;
private File up;
private String upContentType;
private String upFileName;
private String destPath;
public String execute() throws Exception{
System.out.println("contentType==" + this.upContentType);
System.out.println("fileName==" + this.upFileName);
File basePath = new File(ServletActionContext.getServletContext().getRealPath(destPath));
if(!basePath.exists()){
basePath.mkdirs();
}
copy(up, new File(basePath.getCanonicalPath()+"/" + upFileName));
return SUCCESS;
}
public void copy(File srcFile, File destFile) throws IOException{
BufferedInputStream bis = null;
BufferedOutputStream bos = null;
try{
bis = new BufferedInputStream(new FileInputStream(srcFile));
bos = new BufferedOutputStream(new FileOutputStream(destFile));
byte[] buf = new byte[8192];
for(int count = -1; (count = bis.read(buf))!= -1; ){
bos.write(buf, 0, count);
}
bos.flush();
}catch(IOException ie){
throw ie;
}finally{
if(bis != null){
bis.close();
}
if(bos != null){
bos.close();
}
}
}
public File getUp() {
return up;
}
public void setUp(File up) {
this.up = up;
}
public String getUpContentType() {
return upContentType;
}
public void setUpContentType(String upContentType) {
this.upContentType = upContentType;
}
public String getUpFileName() {
return upFileName;
}
public void setUpFileName(String upFileName) {
this.upFileName = upFileName;
}
public String getDestPath() {
return destPath;
}
public void setDestPath(String destPath) {
this.destPath = destPath;
}
}</span></span>
多文件上传的Action
Java代码
<span style="font-size: large;"><span style="font-size: large;">package com.javacrazyer.action;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import org.apache.struts2.ServletActionContext;
import com.opensymphony.xwork2.ActionSupport;
/**
* 批量文件上传
*
* 这里有一点非常重要：就是凡是页面上的file文本域的name=xxx的，
* 那么Action的三个属性必须为xxx,xxxContentType,xxxFileName
*
*
*/
public class BatchFileUploadAction extends ActionSupport {
private static final long serialVersionUID = -7001482935770262132L;
private List<File> up;
private List<String> upContentType;
private List<String> upFileName;
private String destPath;
public String execute() throws Exception{
//System.out.println("contentType==" + this.upContentType);
//System.out.println("fileName==" + this.upFileName);
File basePath = new File(ServletActionContext.getServletContext().getRealPath(destPath));
if(!basePath.exists()){
basePath.mkdirs();
}
int size = up == null ? 0 : up.size();
for(int i = 0; i < size; i++){
/*
* 如果需要限制上传文件的类型，那么可以解开此注释
* if(isAllowType(upContentType.get(i))){
copy(up.get(i), new File(basePath.getCanonicalPath()+"/" + upFileName.get(i)));
}else{
upFileName.remove(i);
}*/
copy(up.get(i), new File(basePath.getCanonicalPath()+"/" + upFileName.get(i)));
}
return SUCCESS;
}
public void copy(File srcFile, File destFile) throws IOException{
BufferedInputStream bis = null;
BufferedOutputStream bos = null;
try{
bis = new BufferedInputStream(new FileInputStream(srcFile));
bos = new BufferedOutputStream(new FileOutputStream(destFile));
byte[] buf = new byte[8192];
for(int count = -1; (count = bis.read(buf))!= -1; ){
bos.write(buf, 0, count);
}
bos.flush();
}catch(IOException ie){
throw ie;
}finally{
if(bis != null){
bis.close();
}
if(bos != null){
bos.close();
}
}
}
public List<File> getUp() {
return up;
}
public void setUp(List<File> up) {
this.up = up;
}
public List<String> getUpContentType() {
return upContentType;
}
public void setUpContentType(List<String> upContentType) {
this.upContentType = upContentType;
}
public List<String> getUpFileName() {
return upFileName;
}
public void setUpFileName(List<String> upFileName) {
this.upFileName = upFileName;
}
public String getDestPath() {
return destPath;
}
public void setDestPath(String destPath) {
this.destPath = destPath;
}
public static boolean isAllowType(String type){
List<String> types = new ArrayList<String>();
types.add("image/pjpeg");
types.add("text/plain");
types.add("image/gif");
types.add("image/x-png");
if(types.contains(type)){
return true;
}else{
return false;
}
}
}</span></span>
针对上面两个Action,都得有那么三个属性【上传的文件，文件类型，文件名】，并且开头必须与表单file的name值一样
在Action中添加一个List<File>类型的与页面所有file域同名的属性。private List<File> up;
添加一个以file域名开头，后面跟ContentType的字符串列表属性，这个由Struts2的文件上传拦截器赋文件类型值。如：private List<String> upContentTyp;
添加一个以file域名开头，后面跟FileName的字符串列表属性，这个由Struts2的文件上传拦截器赋文件名的值。如：private List<String> upFileName;
通过IO流循环操作，完成文件的读写。
记住：在struts2的Action中，对于无论是单个文件上传还是批量上传，就是凡是页面上的file文本域的name=xxx的， 那么Action的三个属性必须为xxx,xxxContentType,xxxFileName
存放上传类型错误信息的资源文件
msg_zh_CN.properties
Xml代码
<span style="font-size: large;"><span style="font-size: large;">struts.messages.error.content.type.not.allowed=\u4E0A\u4F20\u7684\u6587\u4EF6\u7C7B\u578B\u662F\u975E\u6CD5\u7684 #struts.messages.error.uploading=文件不能上传的通用错误信息 #struts.messages.error.file.too.large=上传文件长度过大的错误信息 #struts.messages.error.content.type.not.allowed= 当上传文件不符合指定的contentType</span></span> msg_en_US.properties
Html代码
<span style="font-size: large;"><span style="font-size: large;">struts.messages.error.content.type.not.allowed=upload file contenttype is invalidate</span></span> src/struts.xml
Xml代码
<span style="font-size: large;"><span style="font-size: large;"><?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN"
"http://struts.apache.org/dtds/struts-2.1.7.dtd">
<struts>
<!-- 请求参数的编码方式 -->
<constant name="struts.i18n.encoding" value="UTF-8"/>
<!-- 指定被struts2处理的请求后缀类型。多个用逗号隔开 -->
<constant name="struts.action.extension" value="action,do,go,xkk"/>
<!-- 当struts.xml改动后，是否重新加载。默认值为false(生产环境下使用),开发阶段最好打开 -->
<constant name="struts.configuration.xml.reload" value="true"/>
<!-- 是否使用struts的开发模式。开发模式会有更多的调试信息。默认值为false(生产环境下使用),开发阶段最好打开 -->
<constant name="struts.devMode" value="false"/>
<!-- 设置浏览器是否缓存静态内容。默认值为true(生产环境下使用),开发阶段最好关闭 -->
<constant name="struts.serve.static.browserCache" value="false" />
<!-- 是否允许在OGNL表达式中调用静态方法，默认值为false -->
<constant name="struts.ognl.allowStaticMethodAccess" value="true"/>
<!-- 指定由spring负责action对象的创建
<constant name="struts.objectFactory" value="spring" />-->
<constant name="struts.enable.DynamicMethodInvocation" value="false"/>
<constant name="struts.multipart.maxSize" value="102400000000000" />
<constant name="struts.custom.i18n.resources" value="msg"/>
<package name="my" extends="struts-default" namespace="/">
<interceptors>
<interceptor-stack name="myStack">
<interceptor-ref name="defaultStack"/>
<interceptor-ref name="token"/>
</interceptor-stack>
</interceptors>
<default-interceptor-ref name="myStack"/>
<global-results>
<result name="invalid.token">/error.jsp</result>
</global-results>
<action name="fileUpload" class="com.javacrazyer.action.FileUploadAction">
<param name="destPath">/abc</param>
<result name="input">/index.jsp</result>
<result>/success.jsp</result>
</action>
<action name="batchFileUpload" class="com.javacrazyer.action.BatchFileUploadAction">
<param name="destPath">/abc</param>
<result name="input">/index.jsp</result>
<result>/success.jsp</result>
</action>
</package>
</struts></span></span>
token防止重复提交表单【主要是防止上传过后点击浏览器的后退按钮，再次提交这个问题】
1) 在页面的表单中添加<s:token/>
2) 在要使用token的Action配置中添加token或tokenSession拦截器。
看到没有，我们在配置中还配置了<result name="input">/index.jsp</result>，这样的话，如果上传失败就会跳到index.jsp页面，不过现在
我们还没涉到类型限制的问题，接下来，将的就是如何为上传添加文件类型
struts2中为文件上传添加类型限制有两种方式：
第一种方式在Action纯写代码方式
看BatchFileUploadAction中，copy(up.get(i), new File(basePath.getCanonicalPath()+"/" + upFileName.get(i)));这句话，如果将其上边的被注释的段落注释去掉，将本行注释掉，那么就可以起到文件限制，具体可以在isAllowType这个方法中配置
第二种方式在struts.xml中配置
将上边struts.xml中的
Java代码
<span style="font-size: large;"><span style="font-size: large;"><interceptors>
<interceptor-stack name="myStack">
<interceptor-ref name="defaultStack"/>
<interceptor-ref name="token"/>
</interceptor-stack>
</interceptors></span></span>
替换成下面的
Xml代码
<span style="font-size: large;"><span style="font-size: large;"> <interceptors>
struts2的defaultStack中已经含有fileupload拦截器，如果想加入allowedTypes参数，
需要从新写一个defaultstack ，拷贝过来修改一下
<interceptor-stack name="myStack">
<interceptor-ref name="exception"/>
<interceptor-ref name="alias"/>
<interceptor-ref name="servletConfig"/>
<interceptor-ref name="i18n"/>
<interceptor-ref name="prepare"/>
<interceptor-ref name="chain"/>
<interceptor-ref name="debugging"/>
<interceptor-ref name="profiling"/>
<interceptor-ref name="scopedModelDriven"/>
<interceptor-ref name="modelDriven"/>
修改下面的这些文件类型值，就可以限制上传文件的类型了
<interceptor-ref name="fileUpload">
<param name="allowedTypes">
image/png,image/gif,image/jpeg,text/plain
</param>
</interceptor-ref>
上面配置的是上传文件类型的限制，其实共有两个参数
maximumSize (可选) - 这个拦截器允许的上传到action中的文件最大长度(以byte为单位).
注意这个参数和在webwork.properties中定义的属性没有关系,默认2MB
allowedTypes (可选) - 以逗号分割的contentType类型列表(例如text/html),
这些列表是这个拦截器允许的可以传到action中的contentType.如果没有指定就是允许任何上传类型.
<interceptor-ref name="checkbox"/>
<interceptor-ref name="staticParams"/>
<interceptor-ref name="actionMappingParams"/>
<interceptor-ref name="params">
<param name="excludeParams">dojo\..*,^struts\..*</param>
</interceptor-ref>
<interceptor-ref name="conversionError"/>
<interceptor-ref name="validation">
<param name="excludeMethods">input,back,cancel,browse</param>
</interceptor-ref>
<interceptor-ref name="workflow">
<param name="excludeMethods">input,back,cancel,browse</param>
</interceptor-ref>
Token,防止重复提交
<interceptor-ref name="token"/>
</interceptor-stack>
</interceptors></span></span>
那么具体想添加什么类型就可以在这个配置文件中 <interceptor-ref name="fileUpload">的内容里进行自定义了
现在为止，开发中可能用到的类型大致有如下这么多种,也就是mime类型
Java代码
<span style="font-size: large;">application/vnd.lotus-1-2-3 3gp video/3gpp aab application/x-authoware-bin aam application/x-authoware-map aas application/x-authoware-seg ai application/postscript aif audio/x-aiff aifc audio/x-aiff aiff audio/x-aiff als audio/X-Alpha5 amc application/x-mpeg ani application/octet-stream asc text/plain asd application/astound asf video/x-ms-asf asn application/astound asp application/x-asap asx video/x-ms-asf au audio/basic avb application/octet-stream avi video/x-msvideo awb audio/amr-wb bcpio application/x-bcpio bin application/octet-stream bld application/bld bld2 application/bld2 bmp application/x-MS-bmp bpk application/octet-stream bz2 application/x-bzip2 cal image/x-cals ccn application/x-cnc cco application/x-cocoa cdf application/x-netcdf cgi magnus-internal/cgi chat application/x-chat class application/octet-stream clp application/x-msclip cmx application/x-cmx co application/x-cult3d-object cod image/cis-cod cpio application/x-cpio cpt application/mac-compactpro crd application/x-mscardfile csh application/x-csh csm chemical/x-csml csml chemical/x-csml css text/css cur application/octet-stream dcm x-lml/x-evm dcr application/x-director dcx image/x-dcx dhtml text/html dir application/x-director dll application/octet-stream dmg application/octet-stream dms application/octet-stream doc application/msword dot application/x-dot dvi application/x-dvi dwf drawing/x-dwf dwg application/x-autocad dxf application/x-autocad dxr application/x-director ebk application/x-expandedbook emb chemical/x-embl-dl-nucleotide embl chemical/x-embl-dl-nucleotide eps application/postscript eri image/x-eri es audio/echospeech esl audio/echospeech etc application/x-earthtime etx text/x-setext evm x-lml/x-evm evy application/x-envoy exe application/octet-stream fh4 image/x-freehand fh5 image/x-freehand fhc image/x-freehand fif image/fif fm application/x-maker fpx image/x-fpx fvi video/isivideo gau chemical/x-gaussian-input gca application/x-gca-compressed gdb x-lml/x-gdb gif image/gif gps application/x-gps gtar application/x-gtar gz application/x-gzip hdf application/x-hdf hdm text/x-hdml hdml text/x-hdml hlp application/winhlp hqx application/mac-binhex40 htm text/html html text/html hts text/html ice x-conference/x-cooltalk ico application/octet-stream ief image/ief ifm image/gif ifs image/ifs imy audio/melody ins application/x-NET-Install ips application/x-ipscript ipx application/x-ipix it audio/x-mod itz audio/x-mod ivr i-world/i-vrml j2k image/j2k jad text/vnd.sun.j2me.app-descriptor jam application/x-jam jar application/java-archive jnlp application/x-java-jnlp-file jpe image/jpeg jpeg image/jpeg jpg image/jpeg jpz image/jpeg js application/x-javascript jwc application/jwc kjx application/x-kjx lak x-lml/x-lak latex application/x-latex lcc application/fastman lcl application/x-digitalloca lcr application/x-digitalloca lgh application/lgh lha application/octet-stream lml x-lml/x-lml lmlpack x-lml/x-lmlpack lsf video/x-ms-asf lsx video/x-ms-asf lzh application/x-lzh m13 application/x-msmediaview m14 application/x-msmediaview m15 audio/x-mod m3u audio/x-mpegurl m3url audio/x-mpegurl ma1 audio/ma1 ma2 audio/ma2 ma3 audio/ma3 ma5 audio/ma5 man application/x-troff-man map magnus-internal/imagemap mbd application/mbedlet mct application/x-mascot mdb application/x-msaccess mdz audio/x-mod me application/x-troff-me mel text/x-vmel mi application/x-mif mid audio/midi midi audio/midi mif application/x-mif mil image/x-cals mio audio/x-mio mmf application/x-skt-lbs mng video/x-mng mny application/x-msmoney moc application/x-mocha mocha application/x-mocha mod audio/x-mod mof application/x-yumekara mol chemical/x-mdl-molfile mop chemical/x-mopac-input mov video/quicktime movie video/x-sgi-movie mp2 audio/x-mpeg mp3 audio/x-mpeg mp4 video/mp4 mpc application/vnd.mpohun.certificate mpe video/mpeg mpeg video/mpeg mpg video/mpeg mpg4 video/mp4 mpga audio/mpeg mpn application/vnd.mophun.application mpp application/vnd.ms-project mps application/x-mapserver mrl text/x-mrml mrm application/x-mrm ms application/x-troff-ms mts application/metastream mtx application/metastream mtz application/metastream mzv application/metastream nar application/zip nbmp image/nbmp nc application/x-netcdf ndb x-lml/x-ndb ndwn application/ndwn nif application/x-nif nmz application/x-scream nokia-op-logo image/vnd.nok-oplogo-color npx application/x-netfpx nsnd audio/nsnd nva application/x-neva1 oda application/oda oom application/x-AtlasMate-Plugin pac audio/x-pac pae audio/x-epac pan application/x-pan pbm image/x-portable-bitmap pcx image/x-pcx pda image/x-pda pdb chemical/x-pdb pdf application/pdf pfr application/font-tdpfr pgm image/x-portable-graymap pict image/x-pict pm application/x-perl pmd application/x-pmd png image/png pnm image/x-portable-anymap pnz image/png pot application/vnd.ms-powerpoint ppm image/x-portable-pixmap pps application/vnd.ms-powerpoint ppt application/vnd.ms-powerpoint pqf application/x-cprplayer pqi application/cprplayer prc application/x-prc proxy application/x-ns-proxy-autoconfig ps application/postscript ptlk application/listenup pub application/x-mspublisher pvx video/x-pv-pvx qcp audio/vnd.qcelp qt video/quicktime qti image/x-quicktime qtif image/x-quicktime r3t text/vnd.rn-realtext3d ra audio/x-pn-realaudio ram audio/x-pn-realaudio rar application/x-rar-compressed ras image/x-cmu-raster rdf application/rdf+xml rf image/vnd.rn-realflash rgb image/x-rgb rlf application/x-richlink rm audio/x-pn-realaudio rmf audio/x-rmf rmm audio/x-pn-realaudio rmvb audio/x-pn-realaudio rnx application/vnd.rn-realplayer roff application/x-troff rp image/vnd.rn-realpix rpm audio/x-pn-realaudio-plugin rt text/vnd.rn-realtext rte x-lml/x-gps rtf application/rtf rtg application/metastream rtx text/richtext rv video/vnd.rn-realvideo rwc application/x-rogerwilco s3m audio/x-mod s3z audio/x-mod sca application/x-supercard scd application/x-msschedule sdf application/e-score sea application/x-stuffit sgm text/x-sgml sgml text/x-sgml sh application/x-sh shar application/x-shar shtml magnus-internal/parsed-html shw application/presentations si6 image/si6 si7 image/vnd.stiwap.sis si9 image/vnd.lgtwap.sis sis application/vnd.symbian.install sit application/x-stuffit skd application/x-Koan skm application/x-Koan skp application/x-Koan skt application/x-Koan slc application/x-salsa smd audio/x-smd smi application/smil smil application/smil smp application/studiom smz audio/x-smd snd audio/basic spc text/x-speech spl application/futuresplash spr application/x-sprite sprite application/x-sprite spt application/x-spt src application/x-wais-source stk application/hyperstudio stm audio/x-mod sv4cpio application/x-sv4cpio sv4crc application/x-sv4crc svf image/vnd svg image/svg-xml svh image/svh svr x-world/x-svr swf application/x-shockwave-flash swfl application/x-shockwave-flash t application/x-troff tad application/octet-stream talk text/x-speech tar application/x-tar taz application/x-tar tbp application/x-timbuktu tbt application/x-timbuktu tcl application/x-tcl tex application/x-tex texi application/x-texinfo texinfo application/x-texinfo tgz application/x-tar thm application/vnd.eri.thm tif image/tiff tiff image/tiff tki application/x-tkined tkined application/x-tkined toc application/toc toy image/toy tr application/x-troff trk x-lml/x-gps trm application/x-msterminal tsi audio/tsplayer tsp application/dsptype tsv text/tab-separated-values tsv text/tab-separated-values ttf application/octet-stream ttz application/t-time txt text/plain ult audio/x-mod ustar application/x-ustar uu application/x-uuencode uue application/x-uuencode vcd application/x-cdlink vcf text/x-vcard vdo video/vdo vib audio/vib viv video/vivo vivo video/vivo vmd application/vocaltec-media-desc vmf application/vocaltec-media-file vmi application/x-dreamcast-vms-info vms application/x-dreamcast-vms vox audio/voxware vqe audio/x-twinvq-plugin vqf audio/x-twinvq vql audio/x-twinvq vre x-world/x-vream vrml x-world/x-vrml vrt x-world/x-vrt vrw x-world/x-vream vts workbook/formulaone wav audio/x-wav wax audio/x-ms-wax wbmp image/vnd.wap.wbmp web application/vnd.xara wi image/wavelet wis application/x-InstallShield wm video/x-ms-wm wma audio/x-ms-wma wmd application/x-ms-wmd wmf application/x-msmetafile wml text/vnd.wap.wml wmlc application/vnd.wap.wmlc wmls text/vnd.wap.wmlscript wmlsc application/vnd.wap.wmlscriptc wmlscript text/vnd.wap.wmlscript wmv audio/x-ms-wmv wmx video/x-ms-wmx wmz application/x-ms-wmz wpng image/x-up-wpng wpt x-lml/x-gps wri application/x-mswrite wrl x-world/x-vrml wrz x-world/x-vrml ws text/vnd.wap.wmlscript wsc application/vnd.wap.wmlscriptc wv video/wavelet wvx video/x-ms-wvx wxl application/x-wxl x-gzip application/x-gzip xar application/vnd.xara xbm image/x-xbitmap xdm application/x-xdma xdma application/x-xdma xdw application/vnd.fujixerox.docuworks xht application/xhtml+xml xhtm application/xhtml+xml xhtml application/xhtml+xml xla application/vnd.ms-excel xlc application/vnd.ms-excel xll application/x-excel xlm application/vnd.ms-excel xls application/vnd.ms-excel xlt application/vnd.ms-excel xlw application/vnd.ms-excel xm audio/x-mod xml text/xml xmz audio/x-mod xpi application/x-xpinstall xpm image/x-xpixmap xsit text/xml xsl text/xml xul text/xul xwd image/x-xwindowdump xyz chemical/x-pdb yz1 application/x-yz1 z application/x-compress zac application/x-zaurus-zac zip application/zip </span>
关于office2007的几个常用的mime类型为
.dotx,application/vnd.openxmlformats-officedocument.wordprocessingml.template
.docx,application/vnd.openxmlformats-officedocument.wordprocessingml.document
.xlsx,application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
.pptx,application/vnd.openxmlformats-officedocument.presentationml.presentation
到此，文件类型被限制住了，那么当类型不对时，<result name="input">/index.jsp</result>这个就起作用了，意思
就是凡是上传遇到的类型不是规定类型的文件时，都会跳到index.jsp就是还是上传页面并显示错误信息，错误信息呢是利用了国际化配置在资源文件中的，页面上用 <s:fielderror name="up"></s:fielderror>来显示错误信息
假如我们限制类型为： image/png,image/gif,image/jpeg,text/plain,application/pdf,text/html,application/msword
那么上传的效果为
单独上传
上传后
如果我们不点击返回继续上传，而是点击浏览器上的后退按钮，那么这时TOKEN将起作用，提示下面的页面
如果我们上传一个不在限定类型内的文件的话，也会报错
上传后的结果
对于批量上传
上传后