将图片转成二进制流

Question

                //打开文件
                OpenFileDialog dlg = new OpenFileDialog();
                dlg.Filter = "图片文件(*.jpg;*.bmp;*.png;*.gif)|*.jpg;*.bmp;*.png;*.gif";
                if (dlg.ShowDialog() == DialogResult.OK)
                {
                    FileInfo fileInfo = new FileInfo(dlg.FileName);
                    byte[] buffer = new byte[fileInfo.Length];
                    //using 
                    FileStream stream = fileInfo.OpenRead();                    stream.Read(buffer, 0, buffer.Length);是不是这样写不对啊？

Answer 1

           if (dlg.ShowDialog() == DialogResult.OK)
{
            Stream s=  openFileDialog1.OpenFile();
            byte[] by = new byte[s.Length];
            s.Read(by, 0, by.Length);
}

Answer 2

if (openFileDialog1.ShowDialog() == DialogResult.OK)
{
  Stream s= openFileDialog1.OpenFile();
  byte[] by = new byte[s.Length];
  s.Read(by, 0, by.Length);
}

Answer 3

FileStream fs = new FileStream(dlg.FileName, FileMode.Open, FileAccess.Read, FileShare.Read, 20480, true);
BinaryReader br = new BinaryReader(fs);
byte[] bytes = br.ReadBytes((int)fs.Length);

Answer 4

 private SqlConnection conn=new SqlConnection();
 private SqlCommand cmd=new SqlCommand();1、插入数据库：
 //初始化Connection对象
 conn.ConnectionString=ConfigurationSettings.AppSettings["ConnectionString"];
 conn.Open();
 //初始化Command对象
 cmd.Connection=conn;
 cmd.CommandText="Insert into PICS(ID,PIC) values(1,@pic)";
 //定义二进制数组
 byte[] imagebyte=new byte[1048576];//大小为1MB
 //定义文件流
 FileStream imageStream=new FileStream(Server.MapPath("01.gif"),FileMode.Open,FileAccess.Read);
 //通过文件流读取图片
 imageStream.Read(imagebyte,0,1048576);
 //给CommondText添加属性
 cmd.Parameters.Add("@pic",SqlDbType.Image,(int)(imageStream.Length));
 cmd.Parameters["@pic"].Value=imagebyte;
 cmd.ExecuteNonQuery();
 conn.Close();

Answer 5

//将Image转换为byte[]
public byte[] ConvertImage(Image image)
{
     FileStream fs=new FileStream("imagetemp",FileMode.Create,FileAccess.Write,FileShare.None);
     BinaryFormatter bf = new BinaryFormatter();
     bf.Serialize(fs,(object)image);
     fs.Close();
     fs=new FileStream("imagetemp",FileMode.Open,FileAccess.Read,FileShare.None);
     byte[] bytes = new byte[fs.Length];
     fs.Read(bytes,0,(int)fs.Length);
     fs.Close();
     return bytes;
}