All of us must have come across the fact that some set of codes are specific to a particular OS only and incompatible with others. In some instances they may also lead to system crashes.

In such cases we need to track and identify the OS first and then proceed accordingly. So, here is how you can write a program in VB6.0 that can run in different Windows operating systems.

The first step is to make some simple declarations. Add the following code to your projects declarations.

Private Const VER_PLATFORM_WIN32s = 0
Private Const VER_PLATFORM_WIN32_WINDOWS = 1
Private Const VER_PLATFORM_WIN32_NT As Long = 2

Private Type OSVERSIONINFO
OSVSize As Long
dwVerMajor As Long
dwVerMinor As Long
dwBuildNumber As Long
PlatformID As Long
szCSDVersion As String * 128
End Type

After we are done with the above declaration we can have some methods/functions to determine current OS as shown below.

# 1.
Public Function IdentifyOperatingSystem() As String
Dim rOsVersionInfo As OSVERSIONINFO
Dim sOperatingSystem As String
sOperatingSystem = "NONE"
rOsVersionInfo.OSVSize = Len(rOsVersionInfo)
If GetVersionEx(rOsVersionInfo) Then
Select Case rOsVersionInfo.PlatformID

End Select
End If
End Function

# 2.
Public Function IsWinVista() As Boolean
Dim osv As OSVERSIONINFO
osv.OSVSize = Len(osv)
If GetVersionEx(osv) = 1 Then
IsWinVista = (osv.PlatformID = VER_PLATFORM_WIN32_NT) And (osv.dwVerMajor = 6)
End If
End Function