Go Gin实现文件上传下载的示例代码

router.POST("/resources/common/upload", service.UploadResource)

data:{
    “saveDir”:“保存的路径”，
    “fileName”:“文件名称不带后缀”
  }

// 上传文件
func UploadResource(c *gin.Context) {
 saveDirParam := c.PostForm("saveDir")  // 文件目录
 fileNameParam := c.PostForm("fileName") // 文件名称
 //目录
 var saveDir = ""
 //名称
 var saveName = ""
 //完整路径
 var savePath = ""
 //获取文件
 file, header, errFile := c.Request.FormFile("file")
 //处理获取文件错误
 if errFile != nil || common.IsEmpty(header.Filename) {
   c.JSON(http.StatusOK, gin.H{
     "success": false,
     "message": "请选择文件",
     "dir":   saveDir,
     "name":  saveName,
     "path":  savePath,
   })
   return
 }
 //目录请求参数为空
 if common.IsEmpty(saveDirParam) {
   c.JSON(http.StatusOK, gin.H{
     "success": false,
     "message": "请求参数错误！",
     "dir":   saveDir,
     "name":  saveName,
     "path":  savePath,
   })
   return
 }
 //如果上传的名称为空，则自动生成名称
 if common.IsEmpty(fileNameParam) {
   fileNameParam = GenerateResourceNo()
 }
 //获取上传文件的后缀(类型)
 uploadFileNameWithSuffix := path.Base(header.Filename)
 uploadFileType := path.Ext(uploadFileNameWithSuffix)
 //文件保存目录
 saveDir = "/attachment" + saveDirParam
 //保存的文件名称
 saveName = fileNameParam + uploadFileType
 savePath = saveDir + "/" + saveName
 //打开目录
 localFileInfo, fileStatErr := os.Stat(saveDir)
 //目录不存在
 if fileStatErr != nil || !localFileInfo.IsDir() {
   //创建目录
   errByMkdirAllDir := os.MkdirAll(saveDir, 0755)
   if errByMkdirAllDir != nil {
     logs.Error("%s mkdir error.....", saveDir, errByMkdirAllDir.Error())
     c.JSON(http.StatusOK, gin.H{
       "success": false,
       "dir":   saveDir,
       "name":  saveName,
       "path":  savePath,
       "message": "创建目录失败",
     })
     return
   }
 }
 ////上传文件前 先删除该资源之前上传过的资源文件
 ////（编辑-重新选择文件-需要先删除该资源之前上传过的资源文件）
  ////该代码执行的条件----上传的名称是唯一的，否则会出现误删
 ////获取文件的前缀
 //fileNameOnly := fileNameParam
 //deleteFileWithName(fileNameOnly, saveDir)
 //deleteFileWithName(fileNameOnly, model.WebConfig.ResourcePath+"/"+
 // model.WebConfig.WebConvertToPath)

 out, err := os.Create(savePath)
 if err != nil {
   logs.Error(err)
 }
 defer out.Close()
 _, err = io.Copy(out, file)
 if err != nil {
   c.JSON(http.StatusOK, gin.H{
     "success": false,
     "dir":   saveDir,
     "name":  saveName,
     "path":  savePath,
     "message": err.Error(),
   })
   return
 }

 //没有错误的情况下
 c.JSON(http.StatusOK, gin.H{
   "success": true,
   "dir":   saveDir,
   "name":  saveName,
   "path":  savePath,
   "message": "上传成功",
 })
 return
}

//上传文件
    $.ajaxFileUpload(
      {
        url: '/resources/common/upload', //用于文件上传的服务器端请求地址
        secureuri: false, //是否需要安全协议，一般设置为false
        fileElementId: fileUploadDomId, //文件上传域的ID
        data: {
          "saveDir":fileSaveDir,
          "fileName":fileSaveName
        },
        dataType: 'json', //返回值类型 一般设置为json
        contentType:'application/json',//提交的数据类型
        async: false,
        success: function (data, status) //服务器成功响应处理函数
        {
          if (data.success){
            fileSaveName=fileSaveDir+"/"+data.name;
            console.log("上传成功，返回的文件的路径：",fileSaveName)
          }else{
            console.log("上传失败，返回的文件的路径：",fileSaveName)
            return
          }
        },
        error: function (data, status, e)//服务器响应失败处理函数
        {
          console.log("e==",e);
          return
        }
      }
    );

router.GET("/pub/common/download", service.PubResFileStreamGetService)

//下载次数
func UserFileDownloadCommonService(c *gin.Context) {
  filePath := c.Query("url")
 //打开文件
 fileTmp, errByOpenFile := os.Open(filePath)
 defer fileTmp.Close()
  
  //获取文件的名称
  fileName:=path.Base(filePath)
 if common.IsEmpty(filePath) || common.IsEmpty(fileName) || errByOpenFile != nil {
    logs.Error("获取文件失败")
   c.Redirect(http.StatusFound, "/404")
   return
 } 
 c.Header("Content-Type", "application/octet-stream")
   //强制浏览器下载
 c.Header("Content-Disposition", "attachment; filename="+fileName)
 //浏览器下载或预览
 c.Header("Content-Disposition", "inline;filename="+fileName)
 c.Header("Content-Transfer-Encoding", "binary")
  c.Header("Cache-Control", "no-cache")

 c.File(filePath)
  return
}

router.GET("/pub/common/file_stream", service.PubResFileStreamGetService)

//map for Http Content-Type Http 文件类型对应的content-Type
var HttpContentType = map[string]string{
 ".avi": "video/avi",
 ".mp3": "  audio/mp3",
 ".mp4": "video/mp4",
 ".wmv": "  video/x-ms-wmv",
 ".asf": "video/x-ms-asf",
 ".rm":  "application/vnd.rn-realmedia",
 ".rmvb": "application/vnd.rn-realmedia-vbr",
 ".mov": "video/quicktime",
 ".m4v": "video/mp4",
 ".flv": "video/x-flv",
 ".jpg": "image/jpeg",
 ".png": "image/png",
}

//根据文件路径读取返回流文件 参数url
func PubResFileStreamGetService(c *gin.Context) {
filePath := c.Query("url")
//获取文件名称带后缀
fileNameWithSuffix := path.Base(filePath)
//获取文件的后缀
fileType := path.Ext(fileNameWithSuffix)
//获取文件类型对应的http ContentType 类型
fileContentType := HttpContentType[fileType]
if common.IsEmpty(fileContentType) {
 c.String(http.StatusNotFound, "file http contentType not found")
 return
}
c.Header("Content-Type", fileContentType)
c.File(filePath)
}