在 C# 中向/从 Microsoft SQL SERVER 发送/接收 PictureBox 图像

引言

本文旨在弥补在检索和发送 PictureBox 图像或任何图像到数据库以及反之操作方面缺乏清晰之处。所以各位，不要惊慌，放松一下，因为代码非常简单。

背景

我建议那些仍然不熟悉 SQL 语言，以及广义地说，那些在 .NET 中没有数据库交互知识的人离开此页面并学习上述内容。

Using the Code

完整的代码以及每行注释如下所示。请享受！

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;

//author:Morteza Naeimabadi  Location=IRAN ,Yazd
//written in 2008/03/12

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

        private void button1_Click(object sender, EventArgs e)
        {
            //We are using SQL express.
            //My database name is "PictureDb".
            SqlConnection con = new SqlConnection
                               ("Server=.;database=PictureDb;integrated security=true");
            //I have used a table named "tblUsers" and fill the fields
            SqlCommand com = new SqlCommand("insert into tblUsers
                            (fldCode,fldPic) values(1,@Pic)", con);

            //In here, I have to save the picturebox image to tblUsers
            //because you were not able to send the PictureBox1.Image
            //to field "fldPic" that is of kind
            //"image" in SQL SERVER EXPRESS, then you should do something else
            // and that is converting
            //your picture box image to an array of bytes and then sending
            //that array to database.
            //Below, we have used a stream which will be used to
            //contain our picturebox image bytes.
            MemoryStream stream=new MemoryStream();
            //through the instruction below, we save the
            //image to byte in the object "stream".
            pictureBox1.Image.Save(stream,System.Drawing.Imaging.ImageFormat.Jpeg);

            //Below is the most important part, actually you are
            //transferring the bytes of the array
            //to the pic which is also of kind byte[]
            byte[] pic=stream.ToArray();

            com.Parameters.AddWithValue("@Pic", pic);
            try
            {
                con.Open();
                com.ExecuteNonQuery();
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message);
            }
            finally
            {
                con.Close();
            }
        }

        private void button2_Click(object sender, EventArgs e)
        {
            SqlConnection connect = new SqlConnection
                             ("Server=.;database=PictureDb;integrated security=true");
            SqlCommand command = new SqlCommand
                                ("select fldPic from tblUsers where fldCode=1", connect);
            //for retrieving the image field in SQL SERVER EXPRESS
            //Database you should first bring
            //that image in DataList or DataTable
            //then add the content to the byte[] array.
            //That's ALL!
            SqlDataAdapter dp = new SqlDataAdapter(command);
            DataSet ds = new DataSet("MyImages");

            byte[] MyData = new byte[0];

            dp.Fill(ds, "MyImages");
            DataRow myRow;
            myRow = ds.Tables["MyImages"].Rows[0];

            MyData = (byte[])myRow["fldPic"];

            MemoryStream stream = new MemoryStream(MyData);
            //With the code below, you are in fact converting the byte array of image
            //to the real image.
            pictureBox2.Image = Image.FromStream(stream);
        }
    }
}

历史

• 2008 年 5 月 11 日：初始发布