Android Question Convert any date to milliseconds

Sub AppStart (Form1 As Form, Args() As String)
    Dim p As Period
    p.Initialize
    p.Hours=5
     
    Dim t As Long= DateUtils.AddPeriod(DateTime.Now,p)
    Dim s As Long = DateTime.Now
    Log("t="&(t-s))
    Log(ConvertMillisecondsToString(t-s))
End Sub

Sub ConvertMillisecondsToString(t As Long) As String
    Dim hours, minutes, seconds As Int
    hours = t / DateTime.TicksPerHour
    minutes = (t Mod DateTime.TicksPerHour) / DateTime.TicksPerMinute
    seconds = (t Mod DateTime.TicksPerMinute) / DateTime.TicksPerSecond
    Return $"$1.0{hours}:$2.0{minutes}:$2.0{seconds}"$
End Sub

Dim lngDate As Long    
    Dim MyDate As String ="2020-07-15"
    DateTime.DateFormat="yyyy-MM-dd"
    lngDate = DateTime.DateParse(MyDate)
    Log(lngDate)    'displays   1594785600000
    
    Dim MyDate As String ="15-07-2020"
    DateTime.DateFormat="dd-MM-yyyy"
    lngDate = DateTime.DateParse(MyDate)
    Log(lngDate)
    
    Dim MyDate As String ="07-15-2020"
    DateTime.DateFormat="MM-dd-yyyy"
    lngDate = DateTime.DateParse(MyDate)
    Log(lngDate)