java - 如何解决 No result Defined for action 和 result input 错误？

Question

您好，我想在服务器上上传多个文件，例如一个 Excel 文件和两个 xml 文件，但没有为操作定义结果，并且正在显示结果输入错误。我使用的是struts2框架。

我的 Jsp 页面-

<form action ="myInput" enctype="multipart/form-data" method="post" >
<input type="file" name="fileUpload[]" />
<input type="file" name="fileUpload[]" />
<input type="file" name="fileUpload[]" />
<input  type="submit" value="Upload Records" />
</form>

我的struts.xml-

<package name="links" extends="struts-default, json-default" namespace="/">
<action name="myInput" class="com.action.MyAction" >  
        <interceptor-ref name="linksAccessRequired"/>

        <interceptor-ref name="fileUpload">
            <param name="allowedTypes">*/*</param>
            <param name="maximumSize">10485760</param> <!-- 10MB -->
        </interceptor-ref>
        <interceptor-ref name="defaultStack" />

        <result name="success" type="json"/>
        <result name="login" type="redirect">/</result>  
     </action>
 </package>

我的操作文件-

      import com.opensymphony.xwork2.Action;
      import com.opensymphony.xwork2.ActionSupport;

      import java.io.File;
      import java.io.IOException;

      import javax.servlet.http.HttpServletRequest;
      import javax.servlet.http.HttpSession;

      import org.apache.commons.io.FileUtils;
      import org.apache.struts2.interceptor.ServletRequestAware;

     public class MyAction extends ActionSupport implements ServletRequestAware {
/**
 * 
 */
private static final long serialVersionUID = 1L;
private boolean result = false;
private String status = null;
private String msg = null;

HttpServletRequest request = null;

private File[] fileUpload;
private String[] fileUploadFileName;
private String[] fileUploadContentType;

public File[] getFileUpload() {
    return fileUpload;
}

public void setFileUpload(File[] fileUploads) {
    this.fileUpload = fileUploads;
}

public String[] getFileUploadFileName() {
    return fileUploadFileName;
}

public void setFileUploadFileName(String[] fileUploadFileNames) {
    this.fileUploadFileName = fileUploadFileNames;
}

public String[] getFileUploadContentType() {
    return fileUploadContentType;
}

public void setFileUploadContentType(String[] fileUploadContentTypes) {
    this.fileUploadContentType = fileUploadContentTypes;
}

public String getStatus() {
    return status;
}

public void setStatus(String status) {
    this.status = status;
}

public String getMsg() {
    return msg;
}

public void setMsg(String msg) {
    this.msg = msg;
}

public String execute() {
    System.out.println("Something");
    String saveDirectory = "/mypath/excels/Output/"+request.getSession().getAttribute("my")+"/myOut/";
   if(this.doUpload(fileUpload, saveDirectory))
   {
       this.setStatus("Success");
       this.setMsg("Files have been upload successfully !");
   }
   else
   {
       this.setStatus("Failled");
       this.setMsg("Files have not been upload successfully !");
   }
   return Action.SUCCESS;
}
public boolean doUpload(File[] fileUpload, String saveDirectory) {

    // copy the uploaded files into pre-configured location
    for (int i = 0; i < fileUpload.length; i++) {
        File uploadedFile = fileUpload[i];
        String fileName = fileUploadFileName[i];
        File destFile = new File(saveDirectory + File.separator + fileName);
        try {
            FileUtils.copyFile(uploadedFile, destFile);
        } catch (IOException ex) {
            System.out.println("Could not copy file " + fileName);
            ex.printStackTrace();
        }
    }
    return true;
}

@Override
public void setServletRequest(HttpServletRequest request) {
    this.request = request;
}

}

为什么我收到“没有为操作和结果定义结果输入”错误？ 请建议我解决这个问题。 谢谢

Answer 1

1. 首次阅读 how INPUT result works ，并正确地将其添加到您的操作配置中；

2. 然后阅读 how to upload multiple files in Struts2 ;

3. 此时，您应该能够自己发现错误，即:

   <form action="myInput" enctype="multipart/form-data" method="post" >
       <input type="file" name="fileUpload[]" />
       <input type="file" name="fileUpload[]" />
       <input type="file" name="fileUpload[]" />
       <input type="submit" value="Upload Records" />
   </form>
   

   虽然应该是:

   <form action="myInput" enctype="multipart/form-data" method="post" >
       <input type="file" name="fileUpload[0]" />
       <input type="file" name="fileUpload[1]" />
       <input type="file" name="fileUpload[2]" />
       <input type="submit" value="Upload Records" />
   </form>
   

   或者更好:

   <form action="myInput" enctype="multipart/form-data" method="post" >
       <input type="file" name="fileUpload" multiple />
       <input type="submit" value="Upload Records" />
   </form>
   

   使用 Struts 标签将是:

   <s:form action="myInput" enctype="multipart/form-data" method="post" >
       <s:file name="fileUpload" multiple />
       <s:submit value="Upload Records" />
   </s:form>
   

旁注:如果您有兴趣了解如何使用 dropzone.js 在 Struts2 中执行多重上传，this may be worth reading .