foxpro general field type and c# byte[]
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//The problem is that bytes written to a FoxPro General Field are not being read back in correctly. //This code will write 10 bytes to a general field and then read them back in. When the data is read back it will be incorrect. //Part 1 of 2. Write a byte[] with values 0..9 to a foxpro 'General Field' OleDbConnection oleDbConnection = new OleDbConnection(@"Provider=VFPOLEDB.1;Data Source=c:\blobTest\"); oleDbConnection.Open(); byte[] adtByte = new byte[10]; for(Int16 i = 0; i < 10; i++)//load the array with values 0,1,2,3,4,5,6,7,8,9 adtByte[i] = (byte)i; OleDbCommand command = oleDbConnection.CreateCommand(); command.CommandText = "DELETE FROM image"; //clean up past attempts command.ExecuteNonQuery(); command.CommandText = "INSERT INTO image (image_len, image_val) VALUES (?, ?)"; //foxpro table 'image' has two fields. image_len of type interger and image_val of type general. OleDbParameter p1 = new OleDbParameter("?", OleDbType.Integer); p1.Value = adtByte.Length; command.Parameters.Add(p1); OleDbParameter p2 = new OleDbParameter("?", OleDbType.Binary); p2.Value = adtByte; //write the byte array as type binary - I think this is my problem???? command.Parameters.Add(p2); command.ExecuteNonQuery(); command.Dispose(); //At this point we should have one row in the table and the values should be; // image_len = 10 // image_value = 0123456789 //-------------------------------------------------------------- //Part 2 of 2. Read the row just created back into a pair of variables. OleDbCommand oleDbCommand = new OleDbCommand("Select * from image", oleDbConnection); OleDbDataReader oleDbReader = oleDbCommand.ExecuteReader(); while (oleDbReader.Read()) { object objFieldImage = oleDbReader["image_val"]; byte[] inBytes = (byte[])objFieldImage; object objFieldLen = oleDbReader["image_len"]; int iLen = Convert.ToInt32(objFieldLen); //At this point image_len is 10 as expected. //but inBytes has doubled in size and the value is all wrong. } thanks:^)