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Detailed explanation of HttpPostedFileBase file upload examples

零下一度
零下一度Original
2018-05-11 11:35:2913341browse

This article mainly introduces ASP.NET MVC HttpPostedFileBaseFile upload, which has certain reference value. Interested friends can refer to it

This article introduces ASP.NET MVC HttpPostedFileBase file upload, share it with everyone, I hope it will be helpful to everyone

HttpPostedFileBase file upload supports multiple file uploads at one time. If there are pictures, it supports thumbnail saving

File transfer information encapsulation

/// <summary>
  /// 文件生成方式
  /// </summary>
  public class UpFileMessage
  {
    /// <summary>
    /// 文件名
    /// </summary>
    public string OriginalFileName { get; set; }

    /// <summary>
    /// 是否保存略缩图
    /// </summary>
    public bool IsImage { get; set; }

    /// <summary>
    /// 文件流
    /// </summary>
    public Stream FileStream { get; set; }

    /// <summary>
    /// 生成缩略图的方式
    /// [WH]-指定宽高
    /// [H]-指定高,按比例缩放宽
    /// [W]-指定宽,按比例缩放高
    /// </summary>
    public string Mode { get; set; }

    /// <summary>
    /// 略缩图高度
    /// </summary>
    public int? ThumbHeight { get; set; }

    /// <summary>
    /// 略缩图宽度
    /// </summary>
    public int? ThumbWidth { get; set; }

  }

File upload return result

/// <summary>
  /// 文件上传返回结果
  /// </summary>
  public class UpFileResultMessage
  {
    /// <summary>
    /// 文件保存是否成功
    /// </summary>
    public bool IsSuccess { get; set; }

    /// <summary>
    /// 错误消息
    /// </summary>
    public string Message { get; set; }

    /// <summary>
    /// 原始文件名-(无扩展名)
    /// </summary>
    public string FileName { get; set; }

    /// <summary>
    /// 文件名扩展名
    /// </summary>
    public string FileSuffix { get; set; }

    /// <summary>
    /// 文件名保存路径
    /// </summary>
    public string FilePath { get; set; }

    /// <summary>
    /// 文件类型为图片时
    /// 缩略图保存路径
    /// </summary>
    public string ThumbPath { get; set; }

    /// <summary>
    /// 保存文件名(无扩展名)
    /// </summary>
    public string SaveFileName { get; set; }

    /// <summary>
    /// 文件自增ID
    /// </summary>
    public int[] FileIdArray { get; set; }
  }

File upload classLibrary

Requires a reference to System.Webnamespace, and [System.Web.UI.Page] Inherit and call the Server.MapPath method

public class FileUtil : System.Web.UI.Page
  {
    /// <summary>
    /// 图片上传
    /// </summary>
    /// <param name="fileMessage">文件生成方式</param>
    /// <returns></returns>
    public UpFileResultMessage UpLoadFile(UpFileMessage fileMessage)
    {
      try
      {
        string now = DateTime.Today.ToString("yyyyMMdd");
        string guid = Guid.NewGuid().ToString();

        //获取文件扩展名
        var fileSuffix = Path.GetExtension(fileMessage.OriginalFileName);

        var uploadFolder = Path.Combine(System.Web.HttpContext.Current.Server.MapPath(ParmsConfig.UpFilePathUrl), now);

        if (!Directory.Exists(uploadFolder))
        {
          Directory.CreateDirectory(uploadFolder);
        }

        //保存文件名
        string saveFileName = guid + fileSuffix;
        string filePath = Path.Combine(uploadFolder, saveFileName);


        UpFileResultMessage upFileResult = new UpFileResultMessage()
        {
          IsSuccess = true,
          FileName = Path.GetFileNameWithoutExtension(fileMessage.OriginalFileName),
          FileSuffix = fileSuffix,
          FilePath = string.Format(@"{0}/{1}", ParmsConfig.UpFileIPAddressUrl, now),
          SaveFileName = guid
        };

        using (Stream sourceStream = fileMessage.FileStream)
        {
          using (FileStream targetStream = new FileStream(filePath, FileMode.Create, FileAccess.Write, FileShare.None))
          {
            const int bufferLen = 1024 * 4;//4KB
            byte[] buffer = new byte[bufferLen];
            int count = 0;
            while ((count = sourceStream.Read(buffer, 0, bufferLen)) > 0)
            {
              targetStream.Write(buffer, 0, count);
            }
          }
          //上传文件为图片时,需创建缩略图
          if (fileMessage.IsImage)
          {
            var uploadThumbFolder = Path.Combine(uploadFolder, "Thumb");

            if (!Directory.Exists(uploadThumbFolder))
            {
              Directory.CreateDirectory(uploadThumbFolder);
            }
            using (FileStream targetStream = new FileStream(filePath, FileMode.Open, FileAccess.Read, FileShare.None))
            {
              System.Drawing.Image image = System.Drawing.Image.FromStream(targetStream);
              int width = image.Width;
              int height = image.Height;
              int thumbWidth = 0;
              int thumbHeight = 0;
              switch (fileMessage.Mode)
              {
                case "WH": //指定高宽缩放(可能变形) 
                  thumbWidth = fileMessage.ThumbWidth.HasValue ? fileMessage.ThumbWidth.Value : 200;
                  thumbHeight = fileMessage.ThumbHeight.HasValue ? fileMessage.ThumbHeight.Value : 200;
                  break;
                case "W":  //指定宽,高按比例   
                  thumbWidth = fileMessage.ThumbWidth.HasValue ? fileMessage.ThumbWidth.Value : 200;
                  thumbHeight = height * thumbWidth / width;
                  break;
                case "H":  //指定高,宽按比例
                  thumbHeight = fileMessage.ThumbHeight.HasValue ? fileMessage.ThumbHeight.Value : 200;
                  thumbWidth = width * thumbHeight / height;
                  break;
                default:
                  thumbWidth = fileMessage.ThumbWidth.HasValue ? fileMessage.ThumbWidth.Value : 200;
                  thumbHeight = height * thumbWidth / width;
                  break;
              }
              string thumbFilePath = Path.Combine(uploadThumbFolder, saveFileName);
              CreateThumbnail(thumbFilePath, targetStream, thumbWidth, thumbHeight);
              upFileResult.ThumbPath = string.Format(@"{0}/{1}/Thumb", ParmsConfig.UpFileIPAddressUrl, now);
            }
          }
        }

        return upFileResult;
      }
      catch (Exception ex)
      {
        return new UpFileResultMessage() { IsSuccess = false, Message = ex.Message };
      }

    }

    /// <summary>
    /// 创建指定图片文件流的缩略图
    /// </summary>
    /// <param name="thumbFilePath">缩略图文件保存路径</param>
    /// <param name="fileStream">原始文件流</param>
    /// <param name="width">缩略图宽</param>
    /// <param name="height">缩略图高</param>
    private void CreateThumbnail(string thumbFilePath, Stream fileStream, int width, int height)
    {
      using (Image image = Image.FromStream(fileStream))
      {
        using (Image thumbnail = image.GetThumbnailImage(width, height, null, IntPtr.Zero))
        {
          thumbnail.Save(thumbFilePath);
        }
      }

    }

  }

Calling method

var upFileMsg = new UpFileMessage()
          {
            IsImage = true,
            OriginalFileName = platformImg[i].FileName,
            FileStream = platformImg[i].InputStream,
            ThumbWidth = ThumbWidth,
            Mode = "W"
          };
         var  upFileResultMsg = new FileUtil().UpLoadFile(upFileMsg);

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