VS连接SQL数据库实现图片与数据上传下载

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;
using 个人资料界面;
using System.IO;
using System.Drawing.Imaging;

namespace 个人资料界面
{
    public partial class Form1 : Form
    {
        public string name = "你好";

        public Form1()
        {
            InitializeComponent();
        }
        private void button5_Click_1(object sender, EventArgs e)//上传图片及限制图片大小
        {
          
            //上传图片到数据库
            OpenFileDialog openDlg = new OpenFileDialog();

            openDlg.Filter = "图片文件(*.jpg)|*.jpg*|图片文件(*.gif)|*.gif|图片文件(*.jpeg|*.jpeg"; //文件类型（在框中选择）

         
            string filePath = "";
           
            if (openDlg.ShowDialog() == DialogResult.OK)//如若获取了图片执行以下语句
            {

                filePath = openDlg.FileName;//将获取的文件地址赋给filePath
                //this.txtFilePath.Text = filePath;
                ///////////////////////限制图片大小
                FileInfo fi = new FileInfo(openDlg.FileName);//用fileinfo的方法获取图片
                long _size = fi.Length;//得到图片的字节大小
                if (_size <= 1024 * 1024 * 2)
                {
                    this.picShow.ImageLocation = filePath;//在picturebox控件中显示图片
                    FileStream stream = new FileStream(filePath, FileMode.Open, FileAccess.Read); //打开文件流，用来读取图片文件中的数据                
                    byte[] buffer = new byte[stream.Length]; //将文件流中的数据存入内存字节组中，buffer
                    stream.Read(buffer, 0, (int)stream.Length);
                    stream.Close();
                    try
                    {
                        //调用存储图片数据的存取过程
                        string strName = Path.GetFileName(filePath);
                        SqlConnection conn = DBConnection.MyConnection();
                        conn.Open();
                        SqlCommand cmd = new SqlCommand("proc_UploadPicture", conn);
                        cmd.CommandType = CommandType.StoredProcedure;
                        //cmd.Parameters.Add("@ID", SqlDbType.Int).Value = 1;
                        cmd.Parameters.Add("@Picture", SqlDbType.Image).Value = buffer;//将buffer（内存字节组）赋给sql中的@Picture
                        cmd.Parameters.Add("@Name", SqlDbType.VarChar).Value = name;
                        cmd.ExecuteNonQuery();