以下是我从网上查的,也在用.
选择上传文件页面：selfile.jsp



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<%@ taglib uri="/WEB-INF/struts-html.tld" prefix="html"%>
<html:html>
<html:form action="/uploadsAction.do" enctype="multipart/form-data">
<html:file property="theFile"/>
<html:submit/>
</html:form>
</html:html>

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UpLoadAction.java
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import java.io.*;
import javax.servlet.http.*;
import org.apache.struts.action.*;
import org.apache.struts.upload.FormFile;

/**
* <p>Title:UpLoadAction</p>
* <p>Description: QRRSMMS </p>
* <p>Copyright: Copyright (c) 2004 jiahansoft</p>
* <p>Company: jiahansoft</p>
* @author wanghw
* @version 1.0
*/

public class UpLoadAction extends Action {
  public ActionForward execute(ActionMapping mapping,
                               ActionForm form,
                               HttpServletRequest request,
                               HttpServletResponse response)
      throws Exception {
    if (form instanceof uploadsForm) {//如果form是uploadsForm
        String encoding = request.getCharacterEncoding();
        if ((encoding != null) && (encoding.equalsIgnoreCase("utf-8")))
        {
            response.setContentType("text/html; charset=gb2312");//如果没有指定编码，编码格式为gb2312
        }
        UpLoadForm theForm = (UpLoadForm ) form;
        FormFile file = theForm.getTheFile();//取得上传的文件
        try {
          InputStream stream = file.getInputStream();//把文件读入
          String filePath = request.getRealPath("/");//取当前系统路径
          ByteArrayOutputStream baos = new ByteArrayOutputStream();
          OutputStream bos = new FileOutputStream(filePath + "/" +
                                                  file.getFileName());//建立一个上传文件的输出流
          //System.out.println(filePath+"/"+file.getFileName());
          int bytesRead = 0;
          byte[] buffer = new byte[8192];
          while ( (bytesRead = stream.read(buffer, 0, 8192)) != -1) {
            bos.write(buffer, 0, bytesRead);//将文件写入服务器
          }
          bos.close();
          stream.close();
        }catch(Exception e){
          System.err.print(e);
        }
        //request.setAttribute("dat",file.getFileName());
        return mapping.findForward("display");
    }
    return null;
  }
}



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UpLoadForm.java

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import javax.servlet.http.HttpServletRequest;
import org.apache.struts.action.*;
import org.apache.struts.upload.*;

/**
* <p>Title:UpLoadForm</p>
* <p>Description: QRRSMMS </p>
* <p>Copyright: Copyright (c) 2004 jiahansoft</p>
* <p>Company: jiahansoft</p>
* @author wanghw
* @version 1.0
*/

public class UpLoadForm extends ActionForm {
  public static final String ERROR_PROPERTY_MAX_LENGTH_EXCEEDED = "org.apache.struts.webapp.upload.MaxLengthExceeded";
  protected FormFile theFile;
  public FormFile getTheFile() {
      return theFile;
  }
  public void setTheFile(FormFile theFile) {
      this.theFile = theFile;
  }
  public ActionErrors validate(ActionMapping mapping, HttpServletRequest request)
  {
      ActionErrors errors = null;
      //has the maximum length been exceeded?
      Boolean maxLengthExceeded = (Boolean)
              request.getAttribute(MultipartRequestHandler.ATTRIBUTE_MAX_LENGTH_EXCEEDED);
      if ((maxLengthExceeded != null) && (maxLengthExceeded.booleanValue()))
      {
          errors = new ActionErrors();
          errors.add(ERROR_PROPERTY_MAX_LENGTH_EXCEEDED, new ActionError("maxLengthExceeded"));
      }
      return errors;

  }
}
//这是相对应的form，还有其他属性可以设置，具体可以参考struts的上传例子。




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struts-config.xml

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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE struts-config PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 1.1//EN" "http://jakarta.apache.org/struts/dtds/struts-config_1_1.dtd">
<struts-config>
  <form-beans>
    <form-bean name="uploadsForm" type="UpLoadForm" />
  </form-beans>
  <action-mappings>
    <action name="uploadsForm" type="UpLoadAction" path="/uploadsAction">
      <forward name="display" path="/display.jsp" />
    </action>
  </action-mappings>
</struts-config>
<!--display.jsp就是随便写一个成功页-->

谢谢仁兄了!!
请问上传文件限制大小没有？以及传输速度如何啊?
我从网上了解到采用FTP协议实现文件的上传要快得多(1M以上).

呵呵，我好意思了．
仁兄，可否把文件下载的代码也贴出来参考一下啊．
谢谢罗！！