根据一个大图片自动生成相应小图片的代码

我的一个项目中用的

using System;
using System.IO;
using System.Drawing;

namespace Compoment
{
    /**//// <summary>
    /// ImageLib 的摘要说明。
    /// </summary>
    public class ImageLib
    {
        private string _OrgFileName;
        public string OrgFileName
        {
            get
            {
                return(_OrgFileName);
            }
            set
            {
                _OrgFileName=value;
            }
        }

        private string _OutFileName;
        public string OutFileName
        {
            get
            {
                return(_OutFileName);
            }
            set
            {
                _OutFileName=value;
            }
        }
        public ImageLib()
        {
            //
            // TODO: 在此处添加构造函数逻辑
            //
        }

        public ImageLib(string InFileName,string OutputFileName)
        {
            this.OrgFileName=InFileName;
            this.OutFileName=OutputFileName;
        }

        public void GetSmallPicture(string InFileName,string OutputFileName,int Width)
        {
            this.OrgFileName=InFileName;
            this.OutFileName=OutputFileName;
            if(File.Exists(this.OrgFileName))
            {
                Image MyImage=Image.FromFile(this.OrgFileName);
                Double Diff;
                Diff=Convert.ToDouble(Decimal.Divide(MyImage.Height,MyImage.Width));
                Bitmap ImageOutput=new Bitmap(MyImage,Width,Convert.ToInt32(Math.Ceiling(Width*Diff)));
                MyImage.Dispose();
                ImageOutput.Save(this.OutFileName,System.Drawing.Imaging.ImageFormat.Jpeg);
                ImageOutput.Dispose();
            }
        }

        public string GetSmallPicture(int Width)
        {
            return("");
        }

        ~ImageLib()
        {

        }        
    }
}