二进制图片、二进制pdf 简单的数据库和客户端的交互

本文讲述三点：

1.二进制图片 数据库和客户端的交互

2.二进制pdf 数据库和客户端的交互

3.一个简单的winform打开pdf的方案

前几天辞职了么事做  去书店看书 看到二进制图片上传觉得很简单

图片和pdf都可以显示到winfomr窗体 并且可以下载到本地

数据库中存image和pdf的字段都是 image类型的

1.二进制图片 数据库和客户端的交互(下载到本地参考pdf那个例子)

 private void button1_Click(object sender, EventArgs e)
        {
            try
            {
                //网址不支持  只支持本地文件
                string s = @"E:\MyCode\erjinzhi\erjinzhi\erjinzhi\image\youcai.jpg";
                FileStream f = new FileStream(s, FileMode.Open, FileAccess.Read);
                BinaryReader b = new BinaryReader(f);
                byte[] byteImage = b.ReadBytes((int)f.Length);

                //保存到数据库中 SqlDbType.Image类型
                SqlConnection conn = new SqlConnection("server=.;uid=sa;password=sa;database=test1");
                SqlCommand com = new SqlCommand();
                com.Connection = conn;
                com.CommandType = CommandType.Text;
                com.CommandText = "insert into [user] values(@byteImage)";
                com.Parameters.Add("@byteImage", SqlDbType.Image).Value = byteImage;
                conn.Open();
                int result=com.ExecuteNonQuery();
                conn.Close();
                if (result > 0)
                {
                    com = new SqlCommand();
                    com.Connection = conn;
                    com.CommandText = "select image from [user] where id=@id";
                    com.CommandType = CommandType.Text;
                    com.Parameters.Add("@id", SqlDbType.Int).Value = 1;
                    conn.Open();
                    object obj = com.ExecuteScalar();
                    conn.Close();
                    byteImage = (byte[])obj;
                    MemoryStream m = new MemoryStream(byteImage);
                    //给图片控件设置image
                    pictureBox2.Image = Image.FromStream(m);
                }
            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
        }

2.二进制PDF 数据库和客户端的交互(显示到界面参考下一个实例)

//可以下载到本地之后 把本地地址赋值给axAcroPDF1.src

 private void button2_Click(object sender, EventArgs e)
        {
            try
            {
                //pdf如果大的话 你要把数据库超时时间设置大点 我尝试100M的pdf 结果超时错误
                //pdf加密的话好像也会报错 没有试
                string s = @"F:\桌面\firebug-Firefox_FireBug_调试技巧.pdf";
                FileStream f = new FileStream(s, FileMode.Open, FileAccess.Read);
                BinaryReader b = new BinaryReader(f);
                byte[] bytePdf = b.ReadBytes((int)f.Length);

                //保存到数据库中 SqlDbType.Image类型
                SqlConnection conn = new SqlConnection("server=.;uid=sa;password=sa;database=test1");
                SqlCommand com = new SqlCommand();
                com.Connection = conn;
                com.CommandType = CommandType.Text;
                com.CommandText = "insert into [user] values(@bytePdf)";
                com.Parameters.Add("@bytePdf", SqlDbType.Image).Value = bytePdf;
                conn.Open();
                int result = com.ExecuteNonQuery();
                conn.Close();
                if (result > 0)
                {
                    com = new SqlCommand();
                    com.Connection = conn;
                    com.CommandText = "select image from [user] where id=@id";
                    com.CommandType = CommandType.Text;
                    com.Parameters.Add("@id", SqlDbType.Int).Value = 6;
                    conn.Open();
                    object obj = com.ExecuteScalar();
                    conn.Close();
                    //pdf读取数据库中的二进制 然后报错到本地
                    //参考：http://topic.csdn.net/u/20080415/11/048deb7e-b0c2-4a20-94a5-88be74ce47f0.html
                    bytePdf = (byte[])obj;
                    string filepath = @"E:\xxx.pdf";
                    FileStream fs;
                    if (File.Exists(filepath))
                    {
                        fs = new FileStream(filepath, FileMode.Truncate);
                    }
                    else
                    {
                        fs = new FileStream(filepath, FileMode.CreateNew);
                    }
                    BinaryWriter br = new BinaryWriter(fs);
                    br.Write(bytePdf, 0, bytePdf.Length);
                    br.Close();
                    fs.Close();
                    Process.Start(filepath);
                }

            }
            catch (Exception ex)
            {
                MessageBox.Show(ex.Message.ToString());
            }
            
        }

3.pdf显示到winform窗体的简单的方案

 //在winform窗体中查看PDF
           // 打开工具箱 
            //右键 选择项  com组建选择adobe pdf reader 
            //设置pdf地址src
            //http://dingxq.blog.163.com/blog/static/13052576120108805924575/
            axAcroPDF1.src = @"E:\xxx.pdf";