上传图片并生成小图

<%@ WebHandler Language="C#" class="upload_pic" %>

using System;
using System.Collections.Generic;
using System.Web;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Text;
using System.Collections;
using System.Data;

namespace basic
{
    public class upload_pic : IHttpHandler
    {

        public void ProcessRequest(HttpContext context)
        {
            context.Response.ContentType = "text/plain";
            //获得浏览器端 传过来 第一个文件选择框的数据 

            string isssssss = context.Request["filepath"];
            string dfd = HttpContext.Current.Request.QueryString["filepath"];

            HttpPostedFile hpFile = context.Request.Files[dfd];

            HttpPostedFile hpFile000 = context.Request.Files["licPic"];

            //要保存的目录路径   
            string filePath = "upload";
            //判断 上传文件数据的长度是否>0   
            if (hpFile.ContentLength > 0)
            {
                //获得上传上来的文件名称   
                string fileName = System.IO.Path.GetFileName(hpFile.FileName);
                //获得 要保存的物理路径   
                filePath = context.Server.MapPath(filePath + "/" + fileName);
                //将上传来的 文件数据 保存在 对应的 物理路径上   
                hpFile.SaveAs(filePath);
                //如果上传上来的是图片文件数据   
                if (hpFile.ContentType.IndexOf("image") > -1)
                {
                    //将上传上来的文件对象里的 数据流 转成 图片对象   
                    using (Image img = Image.FromStream(hpFile.InputStream))
                    {
                        //创建缩略图对象   
                        using (Bitmap thumbImg = new Bitmap(120, 40))
                        {
                            //创建 【画家】对象，并告诉他要在缩略图上作画   
                            using (Graphics g = Graphics.FromImage(thumbImg))
                            {
                                //将 原图 img 画在 缩略图 thumbImg上   
                                //第一个长方形参数：要把原图 画成多大   
                                //第二个长方形参数：要画原图的哪个部分(要把原图的哪个部分画到缩略图上)   
                                g.DrawImage(img, new Rectangle(0, 0, thumbImg.Width, thumbImg.Height), new Rectangle(0, 0, img.Width, img.Height), GraphicsUnit.Pixel);
                                string thumbImgPath = context.Server.MapPath("upload/thumb" + fileName);
                                thumbImg.Save(thumbImgPath);
                                context.Response.Write("制作小图成功：" + "/thumb" + fileName);
                            }
                        }
                    }
                }
                context.Response.Write("上传成功：" + hpFile.FileName);
            }
            else
            {
                context.Response.Write("还没有选择要上传的文件！");
            }
        }