利用OpenFileDialog 获取图片存储到数据库中

private void button1_Click(object sender, EventArgs e)
{
string fName;
OpenFileDialog openFileDialog = new OpenFileDialog();//实例化
openFileDialog.InitialDirectory = "e:\\141\\";//打开的默认路径
openFileDialog.Filter = "图像文件 (*.BMP;*.JPG;*.GIF;*.PNG)|*.BMP;*.JPG;*.GIF;*.PNG";
openFileDialog.RestoreDirectory = true;
openFileDialog.FilterIndex = 1;
if (openFileDialog.ShowDialog() == DialogResult.OK)
{
fName = openFileDialog.FileName;
//textBox1.Text = File.ReadAllText(fName);
FileStream fs=new FileStream (fName ,FileMode.Open );
byte [] imgbt=new byte [fs .Length ];
BinaryReader br = new BinaryReader(fs);
imgbt = br.ReadBytes(Convert.ToInt32(fs.Length));
string cnnstr = "server=.;User ID=sa;Password=admin;Database=student";

SqlConnection conn = new SqlConnection(cnnstr);
conn.Open();
SqlCommand comm = new SqlCommand();
comm.Connection = conn;

string sql = "insert into a values('01',@image)";
comm.CommandType = CommandType.Text;
comm.CommandText = sql;
comm.Parameters.Add("image", SqlDbType .Image , imgbt.Length);
comm.Parameters[0].Value = imgbt;
comm.ExecuteNonQuery();
conn.Close();
}

再读取出来

SqlDataReader dr = comm.ExecuteReader();
while (dr.Read())
{
if (dr["imagetest"] != DBNull.Value)
{
MemoryStream ms = new MemoryStream((byte[])dr["imagetest"]);//把照片读到MemoryStream里
Image imageBlob = Image.FromStream(ms, true);//用流创建Image

pictureBox1.Image = imageBlob;//输出图片
}
else//照片字段里没值，清空pb
{
pictureBox1.Image = null;
}
}