Can Create button for Array List?

Question

 I Have the code for add to combo list, how to change to create button

 

 Thank  

{
List<string>[] Addlist;
list_Combo.Items.Clear();
for (int i = 0; i < Addlist[0].Count; i++)
{
//int number = dgDisplay.Rows.Add();
int number = Combo.Items.Add("");
Combo.Items[number] = AddCatlist[0][i];
}
}