将一张图片处理成多张不用尺寸的图片 自动生成缩略图 类似淘宝主图处理

 将一张图片处理成多张不用尺寸的图片  自动生成缩略图

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.IO;
using System.Drawing.Imaging;
using System.Drawing;

public partial class ImageHandler : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        try
        {

            foreach (string f in Request.Files.AllKeys)
            {
               
                CreateNewSizePic(sPath, sPath + fileName, fileName, ".jpg");
               
            }
        }
        catch (Exception ex)
        {
            Response.Write("error");
        }
        Response.End();
    }


  

    /// <summary>
    /// 将一张图片处理成多张不用尺寸的图片
    /// path 文件需要保存的路径(E:新建文件夹2)
    /// orifielpath 当前原图文件的路径(E:新建文件夹1.jpg)
    /// orifilename 原图文件名称（1.jpg）
    /// fileType  原图后缀名（.jpg）
    /// </summary>
    /// <param name="filename"></param>
    public static string CreateNewSizePic(string path, string orifielpath, string orifilename, string fileType)
    {
        Bitmap bm = new Bitmap(orifielpath);
        SaveThumbnail(bm, 310, 310, path, orifilename + "_310X310", fileType);
        SaveThumbnail(bm, 230, 230, path, orifilename + "_230X230", fileType);
        SaveThumbnail(bm, 160, 160, path, orifilename + "_160X160", fileType);
        SaveThumbnail(bm, 80, 80, path, orifilename + "_80X80", fileType);
        SaveThumbnail(bm, 60, 60, path, orifilename + "_60X60", fileType);
        return path;
    }

    private static void SaveThumbnail(Bitmap originBitmap, int width, int height, string directory, string filename, string extension)
    {
        var physicalPath = directory + filename + extension;

        using (var newImage = new Bitmap(width, height))
        {
            using (var graphic = GetGraphic(originBitmap, newImage))
            {
                graphic.DrawImage(originBitmap, 0, 0, width, height);
                using (var encoderParameters = new EncoderParameters(1))
                {
                    encoderParameters.Param[0] = new EncoderParameter(Encoder.Quality, 100L);
                    newImage.Save(physicalPath, ImageCodecInfo.GetImageEncoders().Where(x => x.FilenameExtension.Contains(extension.ToUpperInvariant())).FirstOrDefault(), encoderParameters);
                }
            }
        }
    }

    private static Graphics GetGraphic(System.Drawing.Image originImage, Bitmap newImage)
    {
        newImage.SetResolution(originImage.HorizontalResolution, originImage.VerticalResolution);
        var graphic = Graphics.FromImage(newImage);
        graphic.InterpolationMode = System.Drawing.Drawing2D.InterpolationMode.HighQualityBicubic;
        graphic.SmoothingMode = System.Drawing.Drawing2D.SmoothingMode.HighQuality;
        graphic.PixelOffsetMode = System.Drawing.Drawing2D.PixelOffsetMode.HighQuality;
        graphic.CompositingQuality = System.Drawing.Drawing2D.CompositingQuality.HighQuality;
        return graphic;
    }

}