C#

comboBox1.Items.Add("US");
comboBox1.Items.Add("CA");
//store it in a string
string value = comboBox1.SelectedIndex.ToString();
//store it as an int
int value = comboBox1.SelectedIndex;

public struct CountryWithid {
   public string Country;
   public int Id;

   public CountryWithid(string country, int id) {
      this.Country = country;
      this.Id = id;
   }

   public override string ToString() {
      return this.Country;
   }
}

//adding items
comboBox.Items.Add(new CountryWithId("US", 8));
comboBox.Items.Add(new CountryWithId("Canada", 3));

//retrieving selected Id
int selectedid = ((CountryWithId)comboBox.SelectedItem).Id;

// play sound from a sound resource
	Stream stream=type.Assembly.GetManifestResourceStream(resourceName);
	int len=(int)stream.Length;
	byte[] buf=new byte[len];
	stream.Read(buf, 0, len);
	GCHandle handle=GCHandle.Alloc(buf);
	IntPtr ptr=Marshal.UnsafeAddrOfPinnedArrayElement(buf, 0);
	int res=sndPlaySound(ptr, 4);	// SND_MEMORY
	handle.Free();