testing for one item in dictionary<k,v>

Question

Hey All,

I'm using VS 2005 fx2.0.

If I know my Dictionary contains only 1 item how do I get to it?

Thanks, rod

Answer 1

Make sure you have using System.Linq;. The below command will get the key value pair of the dictionary

var item = Dictionary<k,v>.Single();
var key = item.Key;
var value =item.Value; 

Answer 2

dictionary.SingleOrDefault();

Answer 3

Ngu Soon Hui is correct but to be a bit safer (in the event that there is more than one item) you could do this:

yourDictionary.First();

And to be even safer you could do this (in the event that the dictionary was empty as well):

yourDictionary.FirstOrDefault();

Answer 4

The only way (with framework 2.0) is to iterate over it with foreach.

Or make a method that do that, like:

public static T GetFirstElementOrDefault<T>(IEnumerable<T> values)
{
  T value = default(T);
  foreach(T val in values)
  {
    value = val;
    break;
  }
  return value;
}

It works with all IEnumerable and in your case T is KeyValuePair

Answer 5

Just iterate over all elements of Dictionary (in this case only one)

foreach (KeyValuePair<v, k> keyValue in dictionary)
            {

            }