I need to get the minimum DateTime value of a column in a DataTable. The DataTable is generated dynamically from a CSV file, therefore I don't know the name of that column until runtime. Here is code I've got that doesn't work...

private DateTime GetStartDateFromCSV(string inputFile, string date_attr)
{
    EnumerableRowCollection<DataRow> table = CsvStreamReader.GetDataTableFromCSV(inputFile, "input", true).AsEnumerable();
    DateTime dt = table.Select(record => record.Field<DateTime>(date_attr)).Min();
    return dt;
}

The variable table is broken out just for clarity. I basically need to find the minimum value as a DateTime for one of the columns (to be chosen at runtime and represented by date_attr).

I have tried several solutions from SO (most deal with known columns and/or non-DateTime fields). What I've got throws an error at runtime telling me that it can't do the DateTime conversion (that seems to be a problem with Linq?)

I've confirmed that the data for the column name that is in the string date_attr is a date value.