Is saving blob data concerned with charset?

[Yao Yao]

Hi all:

I use .Net Connector to saving blob data to database, and I found that when saving blob data, some data was translated, so the saved data is not what I expected.
And then I found the problem related with the charset. When I use charset latin1 instead of gbk, the data was saved correctly.

Here is my test sample:

    static void Main( string[] args )
    {
        string connectionString = "Server=localhost;Port=3306;Database=test;Uid=root;Pwd=;";

        MySqlConnection connection = null;

        try
        {
            connection = new MySqlConnection( connectionString );
            connection.Open( );

            MySqlCommand cmd = connection.CreateCommand( );

            MySqlCommand updateCmd = connection.CreateCommand( );
            updateCmd.CommandType = CommandType.Text;
            updateCmd.CommandText = string.Format( "INSERT INTO test.t1( xxx ) VALUES( ?xxx )" );

            byte[] blobData = new byte[2];
            blobData[0] = ( byte )131;
            blobData[1] = ( byte )0;

            MySqlParameter param = new MySqlParameter( "?xxx", MySqlDbType.Blob );
            param.Value = blobData;

            updateCmd.Parameters.Add( param );

            updateCmd.ExecuteNonQuery( );
        }
        finally
        {
            if( connection.State != ConnectionState.Closed )
                connection.Close( );
        }
    }


  CREATE TABLE `t1` (
    `Id` int(11) NOT NULL AUTO_INCREMENT,
    `xxx` blob,
    PRIMARY KEY (`Id`)
  ) ENGINE=InnoDB DEFAULT CHARSET=gbk;

MySQL 5.1.53-community ( Windows XP ) / .Net Connector 5.1.7.0

Also I found when the byte data between 129 and 245, a transition will be done. But why it happened on blob column? Is there someone can guide me? Thanks in advance.