VB API判断数组为空

1.

'API判断数组为空或没有初始化

Private Declare Function SafeArrayGetDim Lib "oleaut32.dll" (ByRef saArray() As Any) As Long  

Private Sub Command1_Click()
Dim tmp() As String
If SafeArrayGetDim(tmp) = 0 Then
MsgBox "数组为空或没有初始化"
End If
End Sub

2.

Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (

                                                                              Destination As Any, Source As Any, ByVal Length As Long)
Private Declare Function VarPtrArray Lib "msvbvm60.dll" Alias "VarPtr" (Var() As Any) As Long

Private Sub Form_Load()
    Dim S() As Long                                            //动态数组
    Dim VarPtrArrayAddress As Long                 //对数组用函数VarPtrArray得到的地址
    Dim SafeArrayPoint As Long                         //'SafeArray结构的指针的值
    
    VarPtrArrayAddress = VarPtrArray(S)

    CopyMemory SafeArrayPoint, ByVal VarPtrArrayAddress, 4   //没有分配内存,这时候SafeArrayPoint的值为0
    If SafeArrayPoint = 0 Then
        MsgBox "空"
    End If

End Sub