Unable to cast object of type 'System.String' to type 'System.Array' Oracle bulk insert

Question

I am trying to insert bulk data in Oracle Table but unfortunately getting this error:

Unable to cast object of type 'System.String' to type 'System.Array'.

I have tried answers from these links but it is not working.

why does this oracle bulk insert not work

put your arrays in a bind

bulk data insertion oracle

Here is my code:

private void InsertInTempMachineResults(ResultObject resultObject)
    {
        string command = @"INSERT INTO ANALYZERS.TEMP_MACHINE_RESULTS (SAMPLE_ID, TEST_ID, TEST_VALUES, " +
            "TEST_VALUES_SYMBOL, TEST_VALUE_UNIT, RESULT_DATE, STRING_ID, MACHINE_ID, PARSING_SOURCE) VALUES(" +
            ":sampleId, :testId, :testValue, :testValueSymbol, :testUnit, SYSDATE, :stringId, :machineId, " +
            ":parsingSource)";

        OracleCommand oracleCommand = new OracleCommand(command, Utils.Connection)
        {
            CommandType = System.Data.CommandType.Text
        };

        oracleCommand.ArrayBindCount = resultObject.ResultItems.Count;
        oracleCommand.BindByName = true;
        OracleParameter[] parameters = {
            new OracleParameter("sampleId", resultObject.SampleId),
            new OracleParameter("testId", OracleDbType.Varchar2, 
                                resultObject.ResultItems.Select(r => r.TestId).ToArray(), ParameterDirection.Input),
            new OracleParameter("testValue", OracleDbType.Varchar2, 
                                resultObject.ResultItems.Select(r => r.TestValue).ToArray(), ParameterDirection.Input),
            new OracleParameter("testValueSymbol", OracleDbType.Varchar2, 
                                resultObject.ResultItems.Select(r => r.Symbol).ToArray(), ParameterDirection.Input),
            new OracleParameter("testUnit", OracleDbType.Varchar2, 
                                resultObject.ResultItems.Select(r => r.Unit).ToArray(), ParameterDirection.Input),
            new OracleParameter("stringId", OracleDbType.Varchar2, resultObject.StringId, ParameterDirection.Input),
            new OracleParameter("machineId", OracleDbType.Varchar2, resultObject.MachineId, ParameterDirection.Input),
            new OracleParameter("parsingSource", OracleDbType.Varchar2, "C#", ParameterDirection.Input),
        };
        oracleCommand.Parameters.AddRange(parameters);
        if (Utils.Connection.State != ConnectionState.Open)
        {
            Utils.Connection.Open();
        }
        try
        {
            int result = oracleCommand.ExecuteNonQuery();
            if (result <= 0)
            {
                Console.WriteLine("ERROR_INSERT_TEMP_MACHINE_RESULTS: {0}", "Unable to add data.");
            }
        }
        catch (Exception e)
        {
            Console.WriteLine("EXCEPTION_INSERT_TEMP_MACHINE_RESULTS: {0}", e.Message);
            throw e;
        }
    }

Thanks

Answer 1

As Patrick Hofman suggested in comment, if you want batch insertion, you have to convert all parameters to Array. Problem Solved.