Make a custom time slider
TimeSliderDialog.cs
// Copyright 2012 ESRI
// 
// All rights reserved under the copyright laws of the United States
// and applicable international laws, treaties, and conventions.
// 
// You may freely redistribute and use this sample code, with or
// without modification, provided you include the original copyright
// notice and use restrictions.
// 
// See the use restrictions.
// 

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Text;
using System.Windows.Forms;
using ESRI.ArcGIS.esriSystem;

namespace MakeACustomTimeControl2008
{
  public partial class TimeSliderDialog : Form
  {
    private CustomTimeSliderButton m_parent = null;

    public TimeSliderDialog(CustomTimeSliderButton parent)
    {
      InitializeComponent();
      m_parent = parent;
      ITimeExtent timeExtent = m_parent.GetTimeExtent();
      m_datePicker.MinDate = new DateTime(timeExtent.StartTime.QueryTicks());
      m_datePicker.MaxDate = new DateTime(timeExtent.EndTime.QueryTicks());
      m_datePicker.Value = m_datePicker.MinDate;
    }

    private void TimeSlider_ValueChanged(object sender, EventArgs e)
    {
      m_parent.UpdateCurrentTime(0.01 * (double)(m_timeSlider.Value));

    }

    private void DatePicker_ValueChanged(object sender, EventArgs e)
    {
      long ticks = m_datePicker.Value.Ticks;
      long minTicks = m_datePicker.MinDate.Ticks;
      long maxTicks = m_datePicker.MaxDate.Ticks;
      double progress = ((double)(ticks - minTicks)) / ((double)(maxTicks - minTicks));
      m_parent.UpdateCurrentTime(progress);

    }
  }
}