Question

It’s difficult to say this right. Basically, I have a List, and I need to get back a string which will be the last in that list of alphabetical order. For example:

If I had the list:

{ "01", "0a2", "test" }

I would need to get back a string that would be next in the alphabetical order, for example “tf”

Answer 1

It’s a bit a hacky answer, but I hope that helps. Assuming you have your strings in a sorted list, I have a litte “quick-and-dirty”-method that generates an item next in alphabetic order:

var items = new System.Collections.Generic.SortedList<string, string>();

items.Add("01", "01");
items.Add("02a", "02a");
items.Add("test", "test");

var nextItem = items.Last().Key;

int pos = nextItem.Length - 1;
while (pos >= 0)
{
   if ((nextItem[pos] != 'z') && (nextItem[pos] != 'Z'))
   {
      nextItem = nextItem.Substring(0, pos - 1) +  Convert.ToChar(Convert.ToInt32(nextItem[pos]) + 1) + nextItem.Substring(pos + 1);
      break;
    }
    pos--;
 }

 if (pos == -1)
 {
    nextItem += "a";
 }