我想使用ASP.NET C＃通过单个文件上传插入两种不同大小的图像

Question

我想使用单个文件上传插入两种不同尺寸的图像。

我插入了一个大小为101的图像，但我需要插入同一用户的另一个51大小的小图像。

id  BigImage    SmallImage
 1  mazhar.jpg  NULL
 2  mazhar.jpg  NULL
 3  12_n.jpg    NULL

我需要如下结果：

 id BigImage    SmallImage
 1  mazhar.jpg  smallmazhar.jpg
 2  mazhar.jpg  smallmazhar.jpg
 3  12_n.jpg    small12_n.jpg

C＃代码如下：

protected void Button1_Click(object sender, EventArgs e)
  {
     //http://forums.asp.net/t/1079883.aspx?PageIndex=1
    string Status = string.Empty;
    int id = 0;

    const int bmpW = 101;
    //New image target width

    const int bmpH = 101;
    //New Image target height

    bo.Para1 = FileUpload1.FileName.ToString();// Passing parameter

    if ((FileUpload1.HasFile))
    {
        //Clear the error label text
        lblError.Text = "";

        //Check to make sure the file to upload has a picture file format extention and set the target width and height

        if ((CheckFileType(FileUpload1.FileName)))
        {
            Int32 newWidth = bmpW;
            Int32 newHeight = bmpH;

            //Use the uploaded filename for saving without the '.' extension

            String upName = FileUpload1.FileName.Substring(0, FileUpload1.FileName.IndexOf("."));

            //Set the save path of the resized image, you will need this directory already created in your web site

       //   string filePath = "~/Upload/" + upName + ".jpg";

            bl.Insert_PhotoInfo(bo, out Status, out id);

            string filePath = Convert.ToString(id) + bo.Para1;

           FileUpload1.PostedFile.SaveAs(Request.ServerVariables["APPL_PHYSICAL_PATH"] + "Upload/" + filePath);

            //Create a new Bitmap using the uploaded picture as a Stream

            //Set the new bitmap resolution to 72 pixels per inch

            Bitmap upBmp = (Bitmap)Bitmap.FromStream(FileUpload1.PostedFile.InputStream);

            Bitmap newBmp = new Bitmap(newWidth, newHeight, System.Drawing.Imaging.PixelFormat.Format24bppRgb);

            newBmp.SetResolution(72, 72);

            //Get the uploaded image width and height

            Double upWidth = upBmp.Width;

            Double upHeight = upBmp.Height;

            int newX = 0;
            //Set the new top left drawing position on the image canvas

            int newY = 0;

            Double reDuce;

            //Keep the aspect ratio of image the same if not 4:3 and work out the newX and newY positions

            //to ensure the image is always in the centre of the canvas vertically and horizontally

            if (upWidth > upHeight)
            {
                //Landscape picture
                reDuce = newWidth / upWidth;

                //calculate the width percentage reduction as decimal
                newHeight = ((Int32)(upHeight * reDuce));

                //reduce the uploaded image height by the reduce amount
                newY = ((Int32)((bmpH - newHeight) / 2));

                //Position the image centrally down the canvas
                newX = 0;
                //Picture will be full width
            }
            else if (upWidth < upHeight)
            {
                //Portrait picture
                reDuce = newHeight / upHeight;

                //calculate the height percentage reduction as decimal
                newWidth = ((Int32)(upWidth * reDuce));

                //reduce the uploaded image height by the reduce amount
                newX = ((Int32)((bmpW - newWidth) / 2));

                //Position the image centrally across the canvas
                newY = 0;
                //Picture will be full hieght
            }
            else if (upWidth == upHeight)
            {
                //square picture
                reDuce = newHeight / upHeight;

                //calculate the height percentage reduction as decimal
                newWidth = ((Int32)(upWidth * reDuce));

                //reduce the uploaded image height by the reduce amount
                newX = ((Int32)((bmpW - newWidth) / 2));
                //Position the image centrally across the canvas


                newY = ((Int32)((bmpH - newHeight) / 2));
                //Position the image centrally down the canvas
            }
            //Create a new image from the uploaded picture using the Graphics class

            //Clear the graphic and set the background colour to white

            //Use Antialias and High Quality Bicubic to maintain a good quality picture

            //Save the new bitmap image using 'Png' picture format and the calculated canvas positioning

            Graphics newGraphic = Graphics.FromImage(newBmp);

            try
            {
                newGraphic.Clear(Color.White);

                newGraphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.AntiAlias;

                newGraphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;

                newGraphic.DrawImage(upBmp, newX, newY, newWidth, newHeight);

                newBmp.Save(MapPath(filePath), System.Drawing.Imaging.ImageFormat.Jpeg);

                //Show the uploaded resized picture in the image control
                Image1.ImageUrl = filePath;
                Image1.Visible = true;
            }
            catch (Exception ex)
            {
                string newError = ex.Message;
                lblError.Text = newError;
            }
            finally
            {
                upBmp.Dispose();
                newBmp.Dispose();
                newGraphic.Dispose();
            }
        }
        else
        {
            lblError.Text = "Please select a picture with a file format extension of either Bmp, Jpg, Jpeg, Gif or Png.";
        }
    }
}

Answer 1

试试这个http://www.c-sharpcorner.com/UploadFile/99bb20/upload-multiple-files-using-fileupload-control-in-Asp-Net-4/它应该对您有用