private void button1_Click(object sender, System.EventArgs e)
{
OleDbConnection mycnn=new OleDbConnection("provider=Microsoft.jet.oledb.4.0;data source=f:\\dazhu.mdb");
mycnn.Open();
OleDbCommand mycmd=new OleDbCommand("update info set picture=@a",mycnn );
FileStream mystream=new FileStream("f:\\1.jpg",FileMode.Open,FileAccess.Read);
long len=mystream.Length;
mycmd.Parameters.Add("@a",OleDbType.Binary,(int)len,"picture");
mycmd.Parameters["@a"].Direction=System.Data.ParameterDirection.Input;
byte []box=new byte[len];
mystream.Read(box,0,(int)len);
mycmd.Parameters["@a"].Value=box;
//更新
mycmd.ExecuteNonQuery();
MessageBox.Show("ok");
mystream.Close();
mycnn.Close();
}