convertir heure locale à utc

Question

J'ai fonction suivante pour obtenir le temps utc. dtuniversal Je passe à str procuré du temps de type de données de serveur sql. cela fonctionne bien jusqu'à 18 heures de l'Est (qui est de 23 utc) il échoue à 19 heures de l'Est (qui est de 24 utc) Je reçois une erreur "Valeur invalide pour cette métadonnée".

Private Function GetUTCTime(ByVal time As TimeSpan) As TimeSpan 

    Dim dt As New DateTime(time.Ticks) 
    dt = dt.ToUniversalTime() 
    Dim dtUniversal As New TimeSpan(dt.Ticks) 
    Return dtUniversal 

End Function 

Answer 1

Le code de test suivant suggère que la variable temps (aTimeSpan) soit examinée.

Private Sub Button1_Click(ByVal sender As System.Object, _ 
          ByVal e As System.EventArgs) Handles Button1.Click 


    Dim ts As New TimeSpan(DateTime.Now.Ticks) 'create a test timespan 
    'Dim ts As New TimeSpan(0,0,0) 'create a test timespan 
    Dim oneHr As New TimeSpan(1, 0, 0) 'one hour increments 

    For x As Integer = 0 To 24 '25 calls to GetUTCTime 
     Debug.WriteLine("  '" & GetUTCTime(ts).ToString) 
     ts = ts.Add(oneHr) 'add one hour 
    Next 
End Sub 

Private Function GetUTCTime(ByVal aTimeSpan As TimeSpan) As TimeSpan 
    'i don't like to use variable names that are keywords 
    Dim dt As New DateTime(aTimeSpan.Ticks) 
    dt = dt.ToUniversalTime() 
    Dim dtUniversal As New TimeSpan(dt.Ticks) 
    Return dtUniversal 

End Function 

'debug output 
'733980.22:23:08.8112022 
'733980.23:23:08.8112022 
'733981.00:23:08.8112022 
'733981.01:23:08.8112022 
'733981.02:23:08.8112022 
'733981.03:23:08.8112022 
'733981.04:23:08.8112022 
'733981.05:23:08.8112022 
'733981.06:23:08.8112022 
'733981.07:23:08.8112022 
'733981.08:23:08.8112022 
'733981.09:23:08.8112022 
'733981.10:23:08.8112022 
'733981.11:23:08.8112022 
'733981.12:23:08.8112022 
'733981.13:23:08.8112022 
'733981.14:23:08.8112022 
'733981.15:23:08.8112022 
'733981.16:23:08.8112022 
'733981.17:23:08.8112022 
'733981.18:23:08.8112022 
'733981.19:23:08.8112022 
'733981.20:23:08.8112022 
'733981.21:23:08.8112022 
'733981.22:23:08.8112022 

Si vous êtes en train de changer de local à UTC et arrière:

'a test date in local time 
Dim d As DateTime = DateTime.Now 
'convert local to UTC 
Dim u As DateTime = d.ToUniversalTime 
'convert UTC to local 
Dim nd As DateTime = u.ToLocalTime 

Soit vous faites ce plus difficile que ce soit, ou je manque quelque chose

Dim d As DateTime = DateTime.Parse("10:00:00") 'this is local central daylight 
    Dim u As DateTime = d.ToUniversalTime 'this is universal 
    d = u.ToLocalTime 'double check