C#

HashSet<int> hash = new HashSet<int>();
Random random = new Random(DateTime.Now.Milliseconds);
int value = 0;
int final = 0;
do
{
    try
    {
        if (hash.Count == 9)
        {
            final++;
            hash.Add(final);
        }
        value = random.Next(1, 10);
        hash.Add(value);
    }
    catch (Exception)
    {
        // eat the exception
    }
}
while (hash.Count < 10)

TestHashSet() completed in
        00:00:00.0380860
TestList() completed in
        00:00:00.0009766

HashSet<int> hash   = new HashSet<int>();
Random       random = new Random(DateTime.Now.Millisecond);
int          value  = 0;
int          start  = 1;
int          stop   = 10;
do
{
    try
    {
        value = random.Next(start, stop);
        hash.Add(value);
        if (value == start)
        {
            start++;
        }
        else if (value == stop)
        {
            stop--;
        }
        if (start == stop && hash.Count < 10)
        {
            hash.Add(start);
        }
    }
    catch (Exception)
    {
        // eat the exception
    }
} while (hash.Count < 10);

meet_ssr wrote:

Performance is a concern

meeram395 wrote:

I have a C# mobile application class.

MSDN[^] states:

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core Role not supported), Windows Server 2008 R2 (Server Core Role not supported), Windows Server 2003 SP2

I are Troll

meeram395 wrote:

The error doesn't have any relation with mobile development.

I are Troll

using System;
using System.Windows.Forms;

namespace MdiApplicationTest
{
    public partial class FormParent : Form
    {
        public FormParent()
        {
            InitializeComponent();
        }

        private void toolStripButtonNewChild_Click(object sender, EventArgs e)
        {
            FormChild child = new FormChild();
            child.MdiParent = this;
            child.Dock = DockStyle.Fill;
            child.Show();
        }

        private void FormParent_FormClosing(object sender, FormClosingEventArgs e)
        {
            if (MdiChildren.Length > 0)
            {
                foreach (Form form in MdiChildren)
                    form.Close();
                e.Cancel = true;
            }
        }
    }
}