asp.net 上传图片并显示在页面

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.Security.Cryptography;
using System.Web.Security;

namespace MobileImgUpload
{
    public partial class imgupload : System.Web.UI.Page
    {
        protected void Page_Load（object sender EventArgs e）
        {

        } 

        protected void btn_upload_Click（object sender EventArgs e）
        {
            Boolean fileOk = false;
            if （pic_upload.HasFile）//验证是否包含文件
            {
                //取得文件的扩展名并转换成小写
                string fileExtension = Path.GetExtension（pic_upload.FileName）.ToLower（）;
                //验证上传文件是否图片格式
                fileOk = IsImage（fileExtension）;

 属性            大小     日期    时间   名称
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     文件       6144  2017-11-14 10:04  MobileImgUpload\MobileImgUpload\bin\MobileImgUpload.dll

     文件      13824  2017-11-14 10:04  MobileImgUpload\MobileImgUpload\bin\MobileImgUpload.pdb

     文件    1986537  2017-11-14 15:02  MobileImgUpload\MobileImgUpload\images\9b59793c876d8821.jpg

     文件       1252  2017-11-14 15:08  MobileImgUpload\MobileImgUpload\imgupload.aspx

     文件       4439  2017-11-14 09:52  MobileImgUpload\MobileImgUpload\imgupload.aspx.cs

     文件       2517  2017-11-14 09:51  MobileImgUpload\MobileImgUpload\imgupload.aspx.designer.cs

     文件       4311  2017-11-14 10:04  MobileImgUpload\MobileImgUpload\MobileImgUpload.csproj

     文件       1089  2017-11-14 10:04  MobileImgUpload\MobileImgUpload\MobileImgUpload.csproj.user

     文件       7018  2018-03-20 19:17  MobileImgUpload\MobileImgUpload\obj\Debug\DesignTimeResolveAssemblyReferencesInput.cache

     文件        434  2017-11-14 09:59  MobileImgUpload\MobileImgUpload\obj\Debug\MobileImgUpload.csproj.FileListAbsolute.txt

     文件       6144  2017-11-14 10:04  MobileImgUpload\MobileImgUpload\obj\Debug\MobileImgUpload.dll

     文件      13824  2017-11-14 10:04  MobileImgUpload\MobileImgUpload\obj\Debug\MobileImgUpload.pdb

     文件       1349  2017-11-14 09:50  MobileImgUpload\MobileImgUpload\Properties\AssemblyInfo.cs

     文件        580  2017-11-14 10:08  MobileImgUpload\MobileImgUpload\Web.config

     文件       1240  2017-11-14 09:50  MobileImgUpload\MobileImgUpload\Web.Debug.config

     文件       1301  2017-11-14 09:50  MobileImgUpload\MobileImgUpload\Web.Release.config

     文件        935  2017-11-14 09:50  MobileImgUpload\MobileImgUpload.sln

    ..A..H.     20480  2018-03-20 19:17  MobileImgUpload\MobileImgUpload.suo

     目录          0  2017-11-14 09:50  MobileImgUpload\MobileImgUpload\obj\Debug\TempPE

     目录          0  2017-11-14 10:04  MobileImgUpload\MobileImgUpload\obj\Debug

     目录          0  2017-11-14 09:59  MobileImgUpload\MobileImgUpload\bin

     目录          0  2017-11-14 15:02  MobileImgUpload\MobileImgUpload\images

     目录          0  2017-11-14 09:50  MobileImgUpload\MobileImgUpload\obj

     目录          0  2017-11-14 09:50  MobileImgUpload\MobileImgUpload\Properties

     目录          0  2017-11-14 10:04  MobileImgUpload\MobileImgUpload

     目录          0  2017-11-14 09:50  MobileImgUpload

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