C# 儲存影像檔到SQL SERVER資料庫，再讀取該檔案並顯示

 需要在SQL SERVER中建立資料庫test, 然後再test中建立一個資料表ImageTable，
含欄位 id  int  自動成長
ImagePath  nchar(50)
Image    image類型

代碼如下：

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using System.Data.SqlClient;
using System.IO;

namespace SaveImageToSqlServer
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void buttonSaveImageToDataServer_Click(object sender, EventArgs e)
        {
            this.folderBrowserDialog1.ShowDialog();

            string dirName = this.folderBrowserDialog1.SelectedPath;
            DirectoryInfo dir = new DirectoryInfo(dirName);
            FileInfo[] fileInfos = dir.GetFiles("*.jpg");                     //擷取檔案夾下所有jpg檔案,因為影像檔都很大的，選取檔案夾下不要有太多圖片，否則Primary區會滿了，系統會提示無法再插入資料。
            List<string> fileList = new List<string>(100);   
            foreach (FileInfo fileInfo in fileInfos)
            {
                fileList.Add(fileInfo.FullName);
                System.Windows.Forms.Application.DoEvents();
            }

            #region Save data to Data Server
            string strConn =                              // 設定連接字串，我是在本機上串連，遠端話需要修改連接字串
                @"Server=(local);"
            + @"Initial Catalog=test;"
            + @"User Id =fisherman;"
            + @"Password=;"
            + @"Integrated Security = true";

            try
            {
                using (SqlConnection sqlConnection = new SqlConnection(strConn))    // 使用using 可以及時釋放資源
                {
                    sqlConnection.Open();
                    foreach (string file in fileList)
                    {
                        // 影像檔存放在資料庫中，需要先轉換成二進位流。使用byte【】來儲存。
                        FileStream fileStream = new FileStream(file, FileMode.Open, FileAccess.Read);
                        byte[] byteImage = new byte[fileStream.Length];
                        fileStream.Read(byteImage, 0, (int)fileStream.Length);
                        
                       //平時寫代碼，對於Insert語句，喜歡直接用“Insert into tableName（a,b)Values(a1,b1)” 是完成，但是對於二進位流，這樣寫
                        // 會報錯，必須按照下面的方式，設定參數名稱類型。
                        string commandText = "Insert into ImageTable(ImagePath, Image)Values(@ImagePath, @Image)";
                        SqlCommand sqlCommand = new SqlCommand(commandText, sqlConnection);
                        sqlCommand.Parameters.Add("@ImagePath", SqlDbType.Text);      // 影像檔路徑
                        sqlCommand.Parameters.Add("@Image", SqlDbType.Binary);         // 影像檔資料，使用二進位格式。
                        sqlCommand.Parameters["@ImagePath"].Value = file;
                        sqlCommand.Parameters["@Image"].Value = byteImage;              // 將映像賦值給command

                        sqlCommand.ExecuteNonQuery();                   

                        System.Windows.Forms.Application.DoEvents();
                    }
                  sqlConnection.Close();       // 用完之後，必須顯示關閉
                }
            }
            catch (SqlException ex)
            {
                MessageBox.Show(ex.ToString());
            }
            #endregion
            MessageBox.Show("Save data OK.");
        }

        private void buttonShowImage_Click(object sender, EventArgs e)
        {
            // 連接字串，同上
            string strConn =
                @"Server=(local);"
            + @"Initial Catalog=test;"
            + @"User id=fisherman;"
            + @"Password=;"
            + @"Integrated Security=true;";

            try
            {
                using (SqlConnection sqlConnection = new SqlConnection(strConn))
                {
                    sqlConnection.Open();
                    string commandText = "Select ImagePath, Image from ImageTable";     // 查詢ImageTable中的資料
                    SqlDataAdapter adapter = new SqlDataAdapter(commandText, sqlConnection);   // 使用DataTable來儲存資料，以便賦值給DataGridView, 函數結束後，表單上的DataGridView會顯示，2列，一列是Image。
                    // Row和Column間距太小，不太好看，不過至少圖片能夠顯示。
                    DataTable dt = new DataTable();
                    adapter.Fill(dt);
                    this.dataGridView1.DataSource = dt;
                    sqlConnection.Close();
                }
            }
            catch (SqlException ex)
            {
                MessageBox.Show(ex.ToString());
            }
        }
    }
}