changing controls which was created dynamically

Create a form and paste the form code with the following code:

 public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {
            CreateLabel();
            CreateLabel();
            CreateLabel();
        }

        private int _count = 1;

        private void CreateLabel()
        {
            Label label = new Label();
            label.Parent = this;
            label.Left = 10;
            label.Top = _count * 30;
            label.Text = "Label " + _count.ToString();
            label.MouseClick += new MouseEventHandler(label_MouseClick);

            ComboBox comboBox = new ComboBox();
            comboBox.Visible = false;
            comboBox.Parent = this;
            comboBox.Top = label.Top;
            comboBox.Left = label.Left;
            comboBox.DropDownStyle = ComboBoxStyle.DropDownList;
            comboBox.Tag = label;
            comboBox.SelectedIndexChanged += new EventHandler(comboBox_SelectedIndexChanged);

            // Fill items
            foreach (string item in GetItems())
                comboBox.Items.Add(item);

            // Store combobox to label tag
            label.Tag = comboBox;

            _count++;
        }

        void comboBox_SelectedIndexChanged(object sender, EventArgs e)
        {
            ((sender as ComboBox).Tag as Label).Show();
            ((sender as ComboBox).Tag as Label).Text = (sender as ComboBox).SelectedItem.ToString();
            (sender as ComboBox).Hide();
        }

        private IEnumerable GetItems()
        {
            yield return "Item 1";
            yield return "Item 2";
            yield return "Item 3";
        }

        void label_MouseClick(object sender, MouseEventArgs e)
        {
            (sender as Label).Hide();
            ((sender as Label).Tag as ComboBox).Show();
        }
    }

You can also try using the attachment in reply.

(mark as answer if solves)