Problem with Lists

Question

I have a List of integers

 List<int> LI = new List<int>();

i wants check whether a particular number exists in the list.if exists do a database updation else do a database insert

foreach (int IT in LI)
        {

        }

can i do this inside the foreach loop or if not possible how to achieve this?????

Answer 1

The easiest way is:

if(LI.Contains(someIntValue))
{
  // do database update
}

Which will search every element in the list and compare it to someIntValue, and return true once an element that matches is found, or false if no element matches.

Now, this is inefficient because the time to search a list is linear. If you are constantly searching your list you should probably be storing your integers in a collection that is better suited for searching such as Dictionary or HashSet which both have constant time

Answer 2

public void InsertUpdateNumber(int i){

    if(LI.Any(li => li == i))
        //do update
    else
        //do insert

}