在 Excel VBA 中使用多维数组进行 ReDim Preserve

Question

我可以让它工作，但不确定这是正确还是最有效的方法。

详细信息：循环遍历 151 行，然后根据列 C 中的条件，仅将这些行中的列 A 和 B 分配给二维数组。根据条件，数组中只需要 151 行中的 114 行。

我知道使用 ReDim Preserve，您只能调整最后一个数组维度的大小，而根本无法更改维度的数量。所以我使用LRow变量将数组中的行调整为总共151行，但我只需要在数组中的实际行在变量ValidRow中，所以看起来（151-114）= 37个多余的行由于 ReDim Preserve 行而在数组中。我想让数组尽可能大，它是 114 行而不是 151 行，但不确定这是否可行，请参阅下面的代码，非常感谢任何帮助，因为我是数组新手，并且已经花费了两个中最好的部分天看着这个。注意：列是常量，它们没有问题，但行会有所不同。

Sub FillArray2()

Dim Data() As Variant
Dim ValidRow, r, LRow As Integer

Sheets("Contract_BR_CONMaster").Select
LRow = Range("A1").End(xlDown).Row '151 total rows

Erase Data()

For r = 2 To LRow
 If Cells(r, 3).Value <> "Bridge From" And Cells(r, 3).Value <> "Bridge To" Then
  ValidRow = ValidRow + 1
  ReDim Preserve Data(1 To LRow, 1 To 2)
  Data(ValidRow, 1) = Range("A" & r).Value 'fills the array with col A
  Data(ValidRow, 2) = Range("B" & r).Value 'fills the array with col B
 End If

Next r

ActiveWorkbook.Worksheets("Test").Range("A2:B" & ValidRow + 1) = Data() 'assign after     loop has run through all data and assessed it

End Sub

Answer 1

我似乎已经通过使用行和列交换的转置来实现这一点，并且仍然使用 ReDim Preserve，然后在分配给范围时在最后转置。这样，数组的大小正是它需要的大小，没有空白单元格。

Sub FillArray3() 'Option 3 works using transposition where row and cols are swapped then swapped back at the end upon assignment to the range with no blank cells as array is sized incrementally via the For/Next loop

Dim Data() As Variant
Dim ValidRow, r, LRow As Integer

Sheets("Contract_BR_CONMaster").Select
LRow = Range("A1").End(xlDown).Row '151 total rows

Erase Data()

For r = 2 To LRow
 If Cells(r, 3).Value <> "Bridge From" And Cells(r, 3).Value <> "Bridge To" Then
  ValidRow = ValidRow + 1
  ReDim Preserve Data(1 To 2, 1 To ValidRow) 'can change the size of only the last dimension if you use Preserve so swapped rows and cols around
  Data(1, ValidRow) = Range("A" & r).Value 'fills the array with col A
  Data(2, ValidRow) = Range("B" & r).Value 'fills the array with col B
 End If

Next r

ActiveWorkbook.Worksheets("Test").Range("A2:B" & ValidRow + 1) = Application.Transpose(Data) 'swap rows and cols back

End Sub

Answer 2

另请注意，REDIM 的内部 VBA 实现不保证在缩小存储空间时释放存储空间。在这种实现中，一个常见的选择是在大小下降到小于输入大小的一半之前不物理地减少存储。

您是否考虑过创建一个类型安全的集合类来存储这些信息而不是数组？在它的最基本形式中（对于 Integer 的存储类型），它看起来是一个类模块，如下所示：

Option Explicit

Private mData As Collection

Public Sub Add(Key As String, Data As Integer)
    mData.Add Key, Data
End Sub

Public Property Get Count() As Integer
    Count = mData.Count
End Property

Public Function Item(Index As Variant) As Integer
    Item = mData.Item(Index)
End Function

Public Sub Remove(Item As Integer)
    mData.Remove Item
End Sub


Private Sub Class_Initialize()
    Set mData = New Collection
End Sub

此实现的一个特殊优势是大小逻辑完全从客户端代码中删除，这是应该的。

请注意，这种模式存储的数据类型可以是 VBA 支持的任何类型，包括数组或其他类。

Answer 3

另外两种方法。 FillArray4 - 创建的初始数组太大，但代码的第二部分使用双循环将其移动到新数组，该循环将数组创建为所需的确切大小。

Sub FillArray4()

Dim Data() As Variant, Data2() As Variant
Dim ValidRow As Integer, r As Integer, lRow As Integer

Sheets("Contract_BR_CONMaster").Select
lRow = Range("A1").End(xlDown).Row '151 total rows

'Part I - array is bigger than it has to be
Erase Data()

For r = 2 To lRow
 If Cells(r, 3).Value <> "Bridge From" And Cells(r, 3).Value <> "Bridge To" Then
  ValidRow = ValidRow + 1 'this is the size the array needs to be 114 rows
  ReDim Preserve Data(1 To lRow, 1 To 2) 'but makes array to be 151 rows as based on lrow not ValidRow as cannot dynamically resize 1st dim of array when using preserve
  Data(ValidRow, 1) = Range("A" & r).Value 'fills the array with col A
  Data(ValidRow, 2) = Range("B" & r).Value 'fills the array with col B
 End If
Next r

'Part II
'move data from Data() array that is too big to new array Data2() that is perfectly sized as it uses ValidRow instead of lrow
Erase Data2()

For i = LBound(Data, 1) To UBound(Data, 1) 'Rows
For j = LBound(Data, 2) To UBound(Data, 2) 'Cols
 If Not IsEmpty(Data(i, j)) Then
  ReDim Preserve Data2(1 To ValidRow, 1 To 2)
  Data2(i, j) = Data(i, j) 'fills the new array with data from original array but only non blank dims; Data2(i,j) is not one particular row or col its an intersection in the array
  'as opposed to part one where you fill the initial array with data from cols A and B using seperate lines for each col
 End If

Next
Next
ActiveWorkbook.Worksheets("Test").Range("A2:B" & ValidRow + 1) = Data2() 'assign data from new array to worksheet

End Sub

Sub FillArray5 - 简单得多，并且是我的首选，因为您只创建一个数组。初始循环确定数组需要的大小，然后第二个循环使用它来创建数组和存储数据。在这两种情况下只注意两个列。我在这种情况下遇到的问题是创建行不同的二维数组。这就是我去热带度假的时候了！

Sub FillArray5()

Dim Data() As Variant
Dim ValidRow As Integer, r As Integer, lRow As Integer, DimCount As Integer,  RemSpaceInArr As Integer

Sheets("Contract_BR_CONMaster").Select
lRow = Range("A1").End(xlDown).Row

Erase Data()

For r = 2 To lRow
 If Cells(r, 3).Value <> "Bridge From" And Cells(r, 3).Value <> "Bridge To" Then
  ValidRow = ValidRow + 1 'this is the size the array needs to be 114 rows
 End If
Next r

DimCount = 0 'reset
 For r = 2 To lRow
  If Cells(r, 3).Value <> "Bridge From" And Cells(r, 3).Value <> "Bridge To" Then
   ReDim Preserve Data(1 To ValidRow, 1 To 2) 'makes array exact size 114 rows using ValidRow from first loop above
   DimCount = DimCount + 1 'need this otherwise ValidRow starts the dim at 114 but needs to start at 1 and increment to max of ValidRow
   Data(DimCount, 1) = Range("A" & r).Value 'fills the array with col A
   Data(DimCount, 2) = Range("B" & r).Value 'fills the array with col B
  End If
 Next r
 RemSpaceInArr = ValidRow - DimCount 'just a check it should be 0

ActiveWorkbook.Worksheets("Test").Range("A2:B" & ValidRow + 1) = Data() 'assign data from array to worksheet

End Sub