how to add dropdownlist selected value to data table in C#.

Question

 

   In run mode as follows

 

      Course Code    AMC (Dropdownlist1)  Major Code AFF (Dropdownlist2)  

 

  i want to add the dropdownlist1 and dropdownlist2 selected value to data table.

 

   for that how can i do in asp.net using c#.