Question

var gender = from row in excel.Worksheet()
             select row["Gender *"].Value.ToString();
string[] genderArray = gender.ToArray().Distinct().ToArray();

in this case the content of genderArray are { “F” , “M” , “M “}

i want that genderArray should only contain { “F” , “M” }

Answer 1

var gender = (from row in excel.Worksheet()
                 select  row["Gender *"].Value.ToString()) ;
    string[]  genderArray = gender.ToArray().Distinct().Select(g=>g.Trim()).ToArray();

You can also do the .Trim in the first query against Value.ToString().Trim().
Edited: I might have misplaced the select in the query.