c#生成缩略图

对应上传后的图片希望加上水印的朋友，可以使用此类。只需要提供几个参数就可以了
using System;
using System.Text;
using System.Drawing;
using System.Drawing.Imaging;
using System.Drawing.Drawing2D;

namespace Baolee.GeneralMethod
{
/// <summary>
/// CropImage 的摘要说明。
/// </summary>
public class CropImage
{
   /// <summary>
   /// 构造函数
   /// </summary>
   public CropImage()
   {
    //
    // TODO: 在此处添加构造函数逻辑
    //
   }
   /// <summary>
   /// 生成缩略图
   /// </summary>
   /// <param name="originalImagePath">源图路径（物理路径）</param>
   /// <param name="thumbnailPath">缩略图路径（物理路径）</param>
   /// <param name="width">缩略图宽度</param>
   /// <param name="height">缩略图高度</param>
   /// <param name="mode">生成缩略图的方式 HW|W|H|Cut </param>
   public static void MakeThumbnail(string originalImagePath, string thumbnailPath, int width, int height, string mode)
   {
    Image image = Image.FromFile(originalImagePath);
    int num = width;
    int num2 = height;
    int x = 0;
    int y = 0;
    int num5 = image.Width;
    int num6 = image.Height;
    string str = mode;
    if (str != null)
    {
     str = string.IsInterned(str);
     if (str != "HW")
     {
      if (str == "W")
      {
       num2 = (image.Height * width) / image.Width;
      }
      else if (str == "H")
      {
       num = (image.Width * height) / image.Height;
      }
      else if (str == "Cut")
      {
       if ((((double) image.Width) / ((double) image.Height)) > (((double) num) / ((double) num2)))
       {
        num6 = image.Height;
        num5 = (image.Height * num) / num2;
        y = 0;
        x = (image.Width - num5) / 2;
       }
       else
       {
        num5 = image.Width;
        num6 = (image.Width * height) / num;
        x = 0;
        y = (image.Height - num6) / 2;
       }
      }
     }
    }
    Image image2 = new Bitmap(num, num2);
    Graphics graphics = Graphics.FromImage(image2);
    graphics.InterpolationMode = InterpolationMode.High;
    graphics.SmoothingMode = SmoothingMode.HighQuality;
    graphics.Clear(Color.Transparent);
    graphics.DrawImage(image, new Rectangle(0, 0, num, num2), new Rectangle(x, y, num5, num6), GraphicsUnit.Pixel);
    try
    {
     image2.Save(thumbnailPath, ImageFormat.Jpeg);
    }
    catch (Exception exception)
    {
     throw exception;
    }
    finally
    {
     image.Dispose();
     image2.Dispose();
     graphics.Dispose();
    }
   }
   }
}