API Question

I am using the following entry out of the win32api

Declare Function GetTimeZoneInformation Lib "kernel32" Alias "GetTimeZoneInformation" (lpTimeZoneInformation As TIME_ZONE_INFORMATION) As Long

I have the following type set up

Type TIME_ZONE_INFORMATION
    zone As Long
End Type

Then in my sub I am doing this

Dim TimeZone As TIME_ZONE_INFORMATION
GetTimeZoneInformation TimeZone     it is this line that is causing the problem

Every time I try to run this it kills VB.  What am I doing wrong.  I have called into the API this way before.
jaalexAsked:
Who is Participating?
 
yowkeeCommented:
Thanks, jaalex. :)

Answer as my comment.
0
 
jaalexAuthor Commented:
Edited text of question
0
 
yowkeeCommented:
The normal declaration TIME_ZONE_INFORMATION should be:

Type SYSTEMTIME
        wYear As Integer
        wMonth As Integer
        wDayOfWeek As Integer
        wDay As Integer
        wHour As Integer
        wMinute As Integer
        wSecond As Integer
        wMilliseconds As Integer
End Type

Type TIME_ZONE_INFORMATION
        Bias As Long
        StandardName(32) As Integer
        StandardDate As SYSTEMTIME
        StandardBias As Long
        DaylightName(32) As Integer
        DaylightDate As SYSTEMTIME
        DaylightBias As Long
End Type
0
Ultimate Tool Kit for Technology Solution Provider

Broken down into practical pointers and step-by-step instructions, the IT Service Excellence Tool Kit delivers expert advice for technology solution providers. Get your free copy now.

 
yowkeeCommented:
jaalex,

  Have you ever call this API in this way in VB? Or in C/C++? What GetTimeZoneInformation's parameter required is a pointer to TIME_ZONE_INFORMATION structure. If you just pass a long type variable into the API with byref, it will cause unpredicted result(who knew what would the memory address from that long variable!). That why you'll get GPF when you run it in VB.
0
 
raygibbinsCommented:
Your declarations should look like this

Option Explicit
Type SYSTEMTIME
        wYear As Integer
        wMonth As Integer
        wDayOfWeek As Integer
        wDay As Integer
        wHour As Integer
        wMinute As Integer
        wSecond As Integer
        wMilliseconds As Integer
End Type
Type TIME_ZONE_INFORMATION
        Bias As Long
        StandardName(32) As Integer
        StandardDate As SYSTEMTIME
        StandardBias As Long
        DaylightName(32) As Integer
        DaylightDate As SYSTEMTIME
        DaylightBias As Long
End Type

Declare Function GetTimeZoneInformation Lib "kernel32" (lpTimeZoneInformation As TIME_ZONE_INFORMATION) As Long

Put the following code on a form, run the prog, and click the form, and get a message box showing weekday

Option Explicit

Private Sub Form_Click()
    Dim TimeZone As TIME_ZONE_INFORMATION
    GetTimeZoneInformation TimeZone
    MsgBox CStr(TimeZone.StandardDate.wDayOfWeek)
End Sub

0
 
yowkeeCommented:
raygibbins,

  Anythings different between your "answer" and my comments???
0
 
raygibbinsCommented:
yowkee,

Not really, but it works, so why is it not accepted yet?
0
 
yowkeeCommented:
raygibbins,

  Please look carefully! I am not the one to ask the question. And you should not post an answer which same as my comment.
  It just like taking other comment and post as answer.
0
 
jaalexAuthor Commented:
Sorry I posted the question and I have been out of town.  I belive that you raygibbins has copied the same thing that yowkee said.  That is why I am rejecting you answer.   Yowkee please answer and I will award you points

0
 
jaalexAuthor Commented:
Sorry for talking so long on grading this.  I
0
 
MirkwoodCommented:
Bought This Question.
0
Question has a verified solution.

Are you are experiencing a similar issue? Get a personalized answer when you ask a related question.

Have a better answer? Share it in a comment.

All Courses

From novice to tech pro — start learning today.