void ReadColumnNames()
{
if (_csvReader.Read()) {
// If column names were already provided then we just skip this row.
if (_names == null) {
_names = new string[_csvReader.FieldCount];
for (int i = 0; i < _csvReader.FieldCount; i++) {
_names[i] = _nt.Add(_csvReader[i]);
}
}
}
}