List<string> FieldListAll = "D1,D2,Tn1,Tn2,A,B,C".ToList();

List<string> FieldList = new List<string>();

foreach (string Field in FieldListAll)

{

double val = (double)this.GetType().GetField("d" + Field).GetValue(this);

if (val>0)

{

FieldList.Add(Field);

}

}