Mobile time issues

Hello,
I have two questions. 1st How can I lockdown the time on a PDA. I'm running an app that keeps track of instances of use and if I can lock down the time I can be sure of my results.

2nd question. IS it possible to write an application to update the time on the lockdown PDA from a timeserver on the internet?

1.
I dont think there is any way to lock down the time as such. But what you can do is locking down you application so the user cannot exit it or access other functions/areas of the device. This can be done by disableing the taskbar and startmenu in your application.

2.
In regards to updating the time. You can update the time and date on the device by using code. If you want you can write your own web service that the device will call and it will return the current date/time to the device. Their maybe other ways of doing it like goin to the world time server page/ parsing it and extracting the time from it (but that's a lot more hassle, than using your own published web service on the internet).

Here is the class for updating the time/date below

VB Code:

Imports System.Runtime.InteropServices
 
Public Class DeviceDateTime
 
    Public Sub New()
 
    End Sub
 
    'System time structure used to pass to P/Invoke...
    <StructLayoutAttribute(LayoutKind.Sequential)> _
    Private Structure SYSTEMTIME
        Public year As Short
        Public month As Short
        Public dayOfWeek As Short
        Public day As Short
        Public hour As Short
        Public minute As Short
        Public second As Short
        Public milliseconds As Short
    End Structure
 
    'P/Invoke dec for setting the system time...
    <DllImport("coredll.dll")> _
    Private Shared Function SetLocalTime(ByRef time As SYSTEMTIME) As Boolean
 
    End Function
 
    Public Function SetDeviceTime(ByVal p_NewDate As Date)
        'Populate structure...
        'Substitute <YOUR DATE OBJECT> with your date object returned via GPRS...
 
        Dim st As SYSTEMTIME
        st.year = p_NewDate.Year
        st.month = p_NewDate.Month
        st.dayOfWeek = p_NewDate.DayOfWeek
        st.day = p_NewDate.Day
        st.hour = p_NewDate.Hour
        st.minute = p_NewDate.Minute
        st.second = p_NewDate.Second
        st.milliseconds = p_NewDate.Millisecond
 
        'Set the new time...
        SetLocalTime(st)
    End Function
End Class