DataTable Find Value - Lambda

int? index = new System.Data.DataView(DTL).ToTable(false, new[] { "Chnum" })
.AsEnumerable()
.Select(row => row.Field("Chnum")) // ie. project the col(s) needed
.ToList()
.FindIndex(col => col == _bdr2_name); // returns 2

chnum = Convert.ToInt32(index);