Publish date: 2013-06-03
Getting System.IO.Stream through OUT-parameter (C#)
//////////////////////////////////////////////////////////////////////////////// //Samples for LCPI ADO.NET Data provider for OLEDB. // 28.05.2013 using System; using System.Data; using lcpi.data.oledb; namespace Sample_0002 { class Program { private const string c_cn_str ="provider=LCPI.IBProvider.3;" +"location=localhost:d:\\database\\ibp_test_fb25_d3.gdb;" +"user id=gamer;" +"password=vermut;"; //---------------------------------------------------------------------- private static byte GenByte(int i) { return (byte)(i%256); }//GenByte //---------------------------------------------------------------------- static int Main(string[] args) { int resultCode=0; try { const int c_bytes=8*1024*1024;//8MB var bytes=new byte[c_bytes]; for(int i=0;i!=c_bytes;++i) bytes[i]=(byte)(i%256); //------ var cn=new OleDbConnection(c_cn_str); cn.Open(); var tr=cn.BeginTransaction(IsolationLevel.RepeatableRead); var cmd=new OleDbCommand("",cn,tr); //INSERT binary data into binary blob through System.IO.MemoryStream object cmd.CommandText="insert into BIN_BLOB_TABLE (BIN_DATA) values (:in)\n" +"returning TEST_ID, BIN_DATA\n" +"into :id, :out"; //implicit generation of command parameters cmd["in"].Value=new System.IO.MemoryStream(bytes); cmd["out"].OutputBinding.Set(OleDbType.IUnknown,typeof(System.IO.Stream)); cmd.ExecuteNonQuery(); Console.WriteLine("record_id: {0}",cmd["id"].Value); var blob_stream=(System.IO.Stream)cmd["out"].Value; //check blob_data for(int i=0;i!=c_bytes;++i) { int b=blob_stream.ReadByte(); if(b!=GenByte(i)) throw new ApplicationException("Wrong blob data!"); }//for //check EOF if(blob_stream.ReadByte()!=-1) throw new ApplicationException("Wrong blob data!"); //Commit transaction tr.Commit(); //----- Console.WriteLine("All is OK."); } catch(Exception e) { resultCode=1; Console.WriteLine(""); Console.WriteLine("ERROR: {0} - {1}",e.Source,e.Message); }//catch return resultCode; }//Main }//class Program }//Sample_0002