J2EE进阶(二)从零开始之Struts2_j2eestruts2

1.引入相应的jar包（commons-fileupload-1.2.1.jar和commons-io-1.3.2.jar）

2.把form的enctype设置为"multipart/form-data"，如下所示：

文件1:

3.在action类中添加如下代码中注释的几个属性。

public class HelloWorldAction {  
    private File upload;//得到上传的文件  
   	private String uploadContentType;//得到上传文件的扩展名  
   	private String uploadFileName;//得到上传文件的名称   
    	public File getUpload() {  
        	return upload;  
    	}  
    	public void setUpload(File upload) {  
        	this.upload = upload;  
    	}  
    	public String getUploadContentType() {  
        	return uploadContentType;  
    	}  
    	public void setUploadContentType(String uploadContentType) {  
        	this.uploadContentType = uploadContentType;  
    	}  
    	public String getUploadFileName() {  
        	return uploadFileName;  
    	}  
    	public void setUploadFileName(String uploadFileName) {  
        	this.uploadFileName = uploadFileName;  
    	}  
    	public String upload() throws IOException {  
        	String realpath = ServletActionContext.getServletContext().getRealPath("/upload");  
        if(upload != null) {  
            File savefile = new File(realpath,uploadFileName);  
            if(!savefile.getParentFile().exists()) {  
                savefile.getParentFile().mkdirs();  
            }  
            FileUtils.copyFile(upload, savefile);  
            ActionContext.getContext().put("msg", "文件上传成功！");  
        }  
        return "success";  
    }  
}

注意，如果在上传的过程中文件的大小超过了struts2默认的文件大小的话，就会上传失败，这时候，可以根据具体的情况设置struts.multipart.maxSize的值来满足上传的需求。

多文件上传

在实际的项目中，有时候可能会要求上传多个文件的情况，下面就来说说上传多个文件的情况。

1.同上。

2.form如下所示：

  
    	文件1:
  
    	文件2:
  
    	文件3:
  
    	  

3.action中添加的几个属性都是数组形式的。

public class HelloWorldAction {  
    	private File[] upload;//得到上传的文件  
    private String[] uploadContentType;//得到上传文件的扩展名  
    private String[] uploadFileName;//得到上传文件的名称    
    public File[] getUpload() {  
        return upload;  
    }  
    public void setUpload(File[] upload) {  
        this.upload = upload;  
    }  
    public String[] getUploadContentType() {  
        return uploadContentType;  
    }  
    public void setUploadContentType(String[] uploadContentType) {  
        this.uploadContentType = uploadContentType;  
    }  
    public String[] getUploadFileName() {  
        return uploadFileName;  
    }  
    public void setUploadFileName(String[] uploadFileName) {  
        this.uploadFileName = uploadFileName;  
    }  
    public String upload() throws IOException {  
        String realpath = ServletActionContext.getServletContext().getRealPath("/upload");  
        if(upload != null) {  
            for(int i=0; i