grails文件上传下载

//1.controller
package com.xdth

class UploadController {

    def index() {
        render(view:"../index")
    }

    /**
     * 文件上传
     * @return
     */
    def upload(){
        /*定义文件上传基本目录*/
        def path = "/upload"
        def basePath = request.getSession().getServletContext().getRealPath(path)

        //检查upload是否存在
        File saveFile = new File(basePath)
        if(!saveFile.exists()){
            saveFile.mkdirs()
        }

        def description = params["description"]
        def file = request.getFile("myFile")
        //上传文件原文件名
        def oldName = file.getOriginalFilename()

        if(file){
            //用时间戳作为新文件名
            def newName = System.currentTimeMillis()+oldName.substring(oldName.lastIndexOf(".",oldName.length()-1))

            //上传文件开始
            file.transferTo(new File(basePath+File.separator+newName))
            Upload upload = new Upload(oldName,newName,basePath,description)
            upload.save()
        }

        flash.message = "${oldName} 上传成功！"
        //从一个action跳转到另一个action
        redirect action:"show",model: [params:params]
    }

    /**
     * 文件下载
     * @return
     */
    def download(){
        def upload = Upload.findById(params.id)
        //File.separator根据当前系统自动获取盘符
        def downloadPath = upload.filePath+File.separator+upload.newName
        def file_name = upload.newName

        def bis = new BufferedInputStream(new FileInputStream(downloadPath))
        def bos = new BufferedOutputStream(response.outputStream)

        long fileLength = new File(downloadPath).length()

        response.setCharacterEncoding("UTF-8")
        response.setContentType("multipart/form-data")

        String userAgent = request.getHeader("User-Agent").toLowerCase()

        if (userAgent.contains("msie") || userAgent.contains("like gecko"))
        {
            // win10 ie edge 浏览器 和其他系统的ie
            file_name = URLEncoder.encode(file_name, "UTF-8")
        }
        else
        {
            file_name = new String(file_name.getBytes("UTF-8"), "iso-8859-1")
        }

        response.setHeader("Content-disposition", String.format("attachment; filename=\"%s\"", file_name))
        response.setHeader("Content-Length", String.valueOf(fileLength))

        byte[] buff = new byte[2048]
        int bytesRead
        while (-1 != (bytesRead = bis.read(buff, 0, buff.length)))
        {
            bos.write(buff, 0, bytesRead)
        }
        bis.close()
        bos.close()
    }

    /**
     * 全部文件查看
     * @return
     */
    def show(){
        def max = Math.min(params.max ? params.max.toInteger() : 10, 100)
        def offset = params.offset ? params.offset.toInteger() : 0

        def queryList = Upload.executeQuery("from Upload",[max:max,offset:offset]).asList()
        respond queryList,view: "show",model: [queryList:queryList,params:params,count:queryList.size()]
    }
}

 

2.index.gsp

    

        
        

            

                

                
文件描述：
            
            

                
上传文件
            
        
        
    

    

        查看全部文件
    

 

3.show.gsp

    
        

            ${flash.message}
        
    

        
        
                
                
                
                
                

            

                
操作
            
            

                    
${it.id}
                    
${it.oldName}
                    
${it.newName}
                    
${it.description}
                    
下载
                
            
        
        
    
    

        

            
            共${count?:0}条   
            
        
    
    

    返回