图片保存到数据库和从数据库读取图片并显示

图片保存到数据库的方法：

public void imgToDB(string sql) { //参数sql中要求保存的imge变量名称为@images //调用方法如：imgToDB("update UserPhoto set Photo=@images where UserNo='" + temp + "'"); FileStream fs = File.OpenRead(t_photo.Text); byte[] imageb = new byte[fs.Length]; fs.Read(imageb, 0, imageb.Length); fs.Close(); SqlCommand com3 = new SqlCommand (sql,con); com3.Parameters.Add("@images", SqlDbType.Image).Value = imageb; if (com3.Connection.State == ConnectionState.Closed) com3.Connection.Open(); try { com3.ExecuteNonQuery(); } catch { } finally { com3.Connection.Close(); } }
数据库中读出图片并显示在picturebox中：

方法一：
private void ShowImage(string sql) { //调用方法如：ShowImage("select Photo from UserPhoto where UserNo='" + userno +"'"); SqlCommand cmd = new SqlCommand(sql, conn); conn.Open(); byte[] b= (byte[])cmd.ExecuteScalar(); if (b.Length 〉 0) { MemoryStream stream = new MemoryStream(b, true); stream.Write(b, 0, b.Length); pictureBox1.Image = new Bitmap(stream); stream.Close(); } conn.Close(); }

方法二：当在dg中选中某行时：
  private void dg_MouseUp(object sender, MouseEventArgs e) { //整行选择 if (e.Button == System.Windows.Forms.MouseButtons.Left) {//用户编号，姓名，性别，身份证号，籍贯，学院，系所，校区，部门，电话，照片 //显示相片 object imgobj=dg[10, dg.CurrentRow.Index].Value; if (imgobj != null && !Convert.IsDBNull(imgobj)) { byte[] imgb = (byte[])imgobj; MemoryStream memStream = new MemoryStream(imgb); try { Bitmap myimge = new Bitmap(memStream); this.pictureBox1.Image = myimge; } catch { DB.msgbox("从数据库读取相片失败！"); } } else pictureBox1.Image = null; } }