convert dataReader to Dictionary

I tried to use LINQ to convert one row to Dictionary (fieldName -> fieldValue)

return Enumerable.Range(0, reader.FieldCount)
                 .ToDictionary<string, object>(reader.GetName, reader.GetValue);

but I received error message:

Instance argument: cannot convert from 'System.Collections.Generic.IEnumerable<int>' to 'System.Collections.Generic.IEnumerable<string>'

How to correct this?