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How to check if VB array is empty

How do I check if the VB array is empty. The followinf code
If LBound(MyArray()) <> -99 Then DoesExist = True
works but throws a floating type exception.

So, how do I check if the array is empty without getting this exception.

1 Solution
Guy Hengel [angelIII / a3]Billing EngineerCommented:

if not MyArray then DoesExists = false
If LBound(MyArray()) <> -99 Then DoesExist = True
Shiju SasidharanAssoc Project ManagerCommented:
Private Sub Form_Load()
Dim MyArray() As String
    If TestArray(MyArray) Then
       MsgBox "Array initialized"
        MsgBox "Array NOT initialized"
    End If
    ReDim MyArray(3)
    If TestArray(MyArray) Then
       MsgBox "Now Array is initialized"
        MsgBox "Array NOT initialized"
    End If
End Sub

Private Function TestArray(MyArray As Variant) As Boolean
On Error GoTo Trap
Dim lSize As Long
    lSize = LBound(MyArray)
    TestArray = True
End Function
Naveen SwamyYash Infinite Solutions Private LimitedCommented:
Private Function isArrayEmpty(arr as Variant)
  Dim i
  isArrayEmpty = False
  On Error Resume Next
  i = Ubound(arr) ' cause an error if array is empty
  If Err.Number > 0 Then Exit Function
  isArrayEmpty = True
End Function

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'=========== Just for information about SafeArray structure - you don't need them for IsArrayDimmed fucntion======
    cElements As Long  ' # of elements in the array dimension
    lLbound   As Long  ' lower bounds of the array dimension
End Type

    cDims       As Integer          ' // Count of dimensions in this array.
    fFeatures   As Integer          ' // Flags used by the SafeArray routines documented below.
    cbElements  As Long             ' // Size of an element of the array.
                                    ' // Does not include size of
                                    ' // pointed-to data.
    cLocks      As Long             ' // Number of times the array has been
                                    ' // locked without corresponding unlock.
    pvData      As Long             ' // Pointer to the data.
    ' Should be sized to cDims:
    rgsabound() As SAFEARRAYBOUND  ' // One bound for each dimension.
End Type
Const VT_BYREF = &H4000&

Private Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (lpDest As Any, lpSource As Any, ByVal cBytes As Long)

Public Function IsArrayDimmed(TheArray As Variant) As Boolean
    Dim lp As Long, VType As Integer
    If Not IsArray(TheArray) Then Exit Function
    Dim nDims As Integer
   ' Get the pointer to the array descriptor (SAFEARRAY structure)
   ' NOTE: A Variant's descriptor, padding & union take up 8 bytes.
   CopyMemory ByVal VarPtr(VType), ByVal VarPtr(TheArray), 2
   CopyMemory ByVal VarPtr(lp), ByVal (VarPtr(TheArray) + 8), 4
   If lp = 0 Then Exit Function
   ' Test if lp is a pointer or a pointer to a pointer.
   If (VType And VT_BYREF) <> 0 Then
      ' Get real pointer to the array descriptor (SAFEARRAY structure)
      CopyMemory ByVal VarPtr(lp), ByVal lp, 4
   End If
   If lp = 0 Then Exit Function
   CopyMemory nDims, ByVal lp, 2
   IsArrayDimmed = CBool(nDims)
End Function

Private Sub Command1_Click()
  Dim abArray()
  MsgBox IsArrayDimmed(abArray)
  ReDim abArray(2, 3)
  MsgBox IsArrayDimmed(abArray)
End Sub
Use the IsEmpty function.

If IsEmpty(MyArray()) = True Then
End If
Note: IsEmpty() only applies to non-array Variant variables.
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