Make a custom time slider
TimeSliderDialog.vb
' 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.
' 

Imports System.Windows.Forms
Imports ESRI.ArcGIS.esriSystem

Partial Public Class TimeSliderDialog
  Inherits Form
  Private m_parent As CustomTimeSliderButton = Nothing

  Public Sub New(ByVal parent As CustomTimeSliderButton)
    InitializeComponent()
    m_parent = parent
    Dim timeExtent As ITimeExtent = 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

  End Sub

  Private Sub TimeSlider_ValueChanged(ByVal sender As Object, ByVal e As EventArgs) Handles m_timeSlider.ValueChanged
    m_parent.UpdateCurrentTime(0.01 * CDbl(m_timeSlider.Value))
  End Sub

  Private Sub DateTimePicker_ValueChanged(ByVal sender As Object, ByVal e As EventArgs) Handles m_datePicker.ValueChanged
    Dim ticks As Long = m_datePicker.Value.Ticks
    Dim minTicks As Long = m_datePicker.MinDate.Ticks
    Dim maxTicks As Long = m_datePicker.MaxDate.Ticks
    Dim progress As Double = (CDbl(ticks - minTicks)) / (CDbl(maxTicks - minTicks))
    m_parent.UpdateCurrentTime(progress)
  End Sub
End Class