Home / Questions / 20638
Accepted
TwoDent
Asked: 2020-08-16 14:51:04 +0800 CST 2020-08-16 14:51:04 +0800 CST

How can I know if a data is a date? (VB.NET)

  • 772

My intention is to know if the data that the user has entered is a date and that it is in the MySQL ( YYYY-MM-DD) format. First I made a query with data type date to an Excel table , but it turns out that when doing a test to see what the query managed, I could notice that the date was captured with numerical values...

Example: A date in my table is "08/16/2005" , but when I do the query, it returns a number ( 38580 in this case).

I do not understand, since it is clear that it is a date, and not a number. I know that in VB.NET we have the function IsDate, or the Date.TryParse... I've already tried to identify them by doing a condition, but it doesn't seem to work. How then could I do to identify if a value is of type date?

         If (Not Date.TryParse(valor(0), fecha)) Then
             MsgBox(valor(0))
             errores += 1
          End If
mysql

1 Answers

  1. Best Answer

    Excel displays dates in the format chosen by the user, but internally stores them as numeric values .

    From VB.NET the function can be used Date.FromOADate()to obtain the date corresponding to the value delivered by Excel . ( OA=OLE Automation )

        Date.FromOADate(38580)
    ' Resultado: #8/16/2005# '

    ' Para pasar al formato YYYY-MM-DD '
    Date.FromOADate(38580).ToString("yyyy-MM-dd")
    ' Resultado: "2005-08-16" '

    To check the custom formats for date, you can go to this msdn link .

    • 1