public List refrence;
public MainWindow()
{
InitializeComponent();
refrence = new List<int>();
}
private void buttonAdd_Click(object sender, RoutedEventArgs e)
{
refrence.Add(int.Parse(textBox.Text));
textBox.Clear();
listBox.Items.Clear();
}
private void buttonSearch_Click(object sender, RoutedEventArgs e)
{
List<int> q = new List<int>();
int[] query = refrence.ToArray();
for (int i = 0; i < query.Length; i++)
for (int j = i + 1; j < query.Length; j++)
{
if (query[i] == query[j])
{
q.Add(query[j]);
var qwe = q.Distinct();
foreach(var item in qwe)
listBox.Items.Add(item);
}
}
}</i>
But it shows
5
5
5
16
5
16 in listBox