Set the time extents for a layer then render the layer
SetTimeExtentsButton.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.Carto
Imports ESRI.ArcGIS.Display
Imports ESRI.ArcGIS.esriSystem
Imports ESRI.ArcGIS.ArcMapUI


Public Class SetTimeExtentsButton
  Inherits ESRI.ArcGIS.Desktop.AddIns.Button

  Public Sub New()

  End Sub

  Protected Overrides Sub OnClick()
    Dim pMxDoc As IMxDocument = My.ArcMap.Document
    Dim pMap As IMap = pMxDoc.FocusMap
    Dim sampeMapFileName As String = "BasicHurricanes.mxd"

    If pMap.LayerCount < 1 Then
      MessageBox.Show("Before running this sample, load the associated file '" & sampeMapFileName & "'")
      Return
    End If

    If pMap.Layer(0).Name <> "atlantic_hurricanes_2000" Then
      MessageBox.Show("Before running this sample, load the associated file '" & sampeMapFileName & "'")
      Return
    End If

    Dim pTZFac As ITimeZoneFactory = New TimeZoneFactoryClass()
        'making the first layer of the focused map time-aware
    Dim pFLyr As IFeatureLayer = TryCast(pMap.Layer(0), IFeatureLayer)
    Dim pTimeData As ITimeData = TryCast(pFLyr, ITimeData)

    If pTimeData.SupportsTime Then
      pTimeData.UseTime = True
      Dim pTimeDataDef As ITimeTableDefinition = TryCast(pFLyr, ITimeTableDefinition)
      pTimeDataDef.StartTimeFieldName = "Date_Time"
      pTimeDataDef.TimeReference = pTZFac.CreateTimeReferenceFromWindowsID(pTZFac.QueryLocalTimeZoneWindowsID)
      Dim pTimeAnimProp As ITimeDataDisplay = TryCast(pFLyr, ITimeDataDisplay)
      pTimeAnimProp.TimeIntervalUnits = ESRI.ArcGIS.esriSystem.esriTimeUnits.esriTimeUnitsHours
      pTimeAnimProp.TimeInterval = 12.0
    End If

    '
    Dim pActiveView As IActiveView = TryCast(pMap, IActiveView)
    Dim pScreenDisplay As IScreenDisplay = pActiveView.ScreenDisplay
    Dim pTimeDisplay As ITimeDisplay = TryCast(pScreenDisplay, ITimeDisplay)
    pTimeDisplay.TimeReference = pTZFac.CreateTimeReferenceFromWindowsID(pTZFac.QueryLocalTimeZoneWindowsID)

    Dim pStartTime As ITime = New TimeClass()
    pStartTime.Year = 2000
    pStartTime.Month = 9
    pStartTime.Day = 25
    Dim pEndTime As ITime = New TimeClass()
    pEndTime.Year = 2000
    pEndTime.Month = 9
    pEndTime.Day = 30

    Dim pTimeExt As ITimeExtent = New TimeExtentClass()
    pTimeExt.StartTime = pStartTime
    pTimeExt.EndTime = pEndTime
    pTimeDisplay.TimeValue = TryCast(pTimeExt, ITimeValue)

    pActiveView.ContentsChanged()
  End Sub

  Protected Overrides Sub OnUpdate()
    Enabled = True
  End Sub
End Class