date of birth control for visual 2005

Hi, I'd recommend using a third party DateTimePicker control for your web application. Alternatively it's quite simple to create your own day/month/year selecting control... The following example would be better if you encapsulated it into a single user control project, then imported that into your application. Anyway, to give you an idea, follow these steps:

1. Add three drop down lists to your web form, name them, ddlDay, ddlMonth and ddlYear.
2. For the ddlMonth and ddlYear drop down lists, set their AutoPostBack property to true.
3. In your web form load event add:
        if (!this.IsPostBack)
        {
            int i;

            for (i = 1; i <= DateTime.DaysInMonth(DateTime.Today.Year, DateTime.Today.Month); i++)
                this.ddlDay.Items.Add(i.ToString());

            for (i = 1; i <= 12; i++)
                this.ddlMonth.Items.Add(i.ToString());

            for (i = 1900; i < DateTime.Today.Year; i++)
                this.ddlYear.Items.Add(i.ToString());
        }

4. Add the following method to your web form code behind:

private void ResetDays()
    {
        int selectedIndex = this.ddlDay.SelectedIndex;

        this.ddlDay.Items.Clear();
        for (int i = 1; i <= DateTime.DaysInMonth(int.Parse(this.ddlYear.SelectedValue), int.Parse(this.ddlMonth.SelectedValue)); i++)
            this.ddlDay.Items.Add(i.ToString());

        this.ddlDay.SelectedIndex = (selectedIndex > this.ddlDay.Items.Count - 1) ? 0 : selectedIndex;
    }

5. For the ddlMonth and ddlYear drop down lists, create  SelectedIndexChanged event handlers, then call the ResetDays() method in them, so you should have something like:

protected void ddlMonth_SelectedIndexChanged(object sender, EventArgs e)
    {
        this.ResetDays();
    }

    protected void ddlYear_SelectedIndexChanged(object sender, EventArgs e)
    {
        this.ResetDays();
    }
6. Finally, to get the selected date you can have something like:

        DateTime dt = new DateTime(int.Parse(this.ddlYear.SelectedValue),
                                   int.Parse(this.ddlMonth.SelectedValue),
                                   int.Parse(this.ddlDay.SelectedValue));

        this.Label1.Text = "You were born on " + dt.ToShortDateString();

--
Like I said, it would be better to encapsulate all this into a single composite user control, then you can easily reuse the control in different projects and different web forms. If you google for "C# ASP.NET DateTimePicker" you'll find a few third party controls that you can use too.