Question

I am having two list<string> as follows

listA is having the following values 10,20,30,40 and

listB is having the following values 10,20,30

If listB contains listA elements i would like to enable particular controls if not i would like to disable the Controls

I tried of using two loops as follows

for(int ilist1=0;ilist1<listA.count;ilist1++)
{
  for(int ilist2=0;ilist2<listB.count;ilist2++)
  {
      if(listA[ilist1]==listB[ilist2])
      {
           //Enable particular control
      }
  }
}

But i know this is not an appropriate one to do so can any one tell me the best approach to achieve this

Answer 1

What you want to do is to hash the items in the first list into a set then verify for each item in the second is within the set. Unfortunately the HashSet<> is not available so the closest you can get is the Dictionary<,>.

Do this:

Dictionary<string, string> set = new Dictionary<string, string>();
foreach (string item in listA)
{
    set.Add(item, item);
}

foreach (string item in listB)
{
    if (!set.ContainsKey(item))
    {
        //Enable particular control
    }
}