摘要:我遍历多行数据,每次通过循环将来自不同列的数据存储在大约 6 个不同的变量中
问题:Range("A" & some iterator)
与 相比,我会节省大量的 CPU 周期ActiveCell.Offset(some number)
吗?一个比另一个快多少?
提前致谢!
出于纯粹的无聊和一点好奇,我为各种方法组合了一个粗略的计时器来循环 100,000 个 Excel 单元格。
理想情况下,您应该每次运行多次并取平均值,但它会给您一个粗略的速度轮廓。
在我的机器上,这就是我得到的
Option Explicit
#If Win64 Then
Public Declare PtrSafe Function GetTickCount Lib "kernel32" () As Long
#Else
Public Declare Function GetTickCount Lib "kernel32" () As Long
#End If
Sub TestSpeedofReadingCells()
Dim tcStart As Long
Dim tcEnd As Long
Dim temp As Variant
Dim i As Long
Dim rngobject As Range
Dim rngItem As Range
Dim rngArray() As Variant
Const rowsToRead As Long = 100000
'***Read individual cells using .Range
With Sheet1
tcStart = GetTickCount
For i = 1 To rowsToRead
temp = .Range("A" & i).Value
Next i
tcEnd = GetTickCount
Debug.Print "Time1: " & tcEnd - tcStart
End With
'***Read individual cells using .Range & screenupdating off
With Sheet1
Application.ScreenUpdating = False
tcStart = GetTickCount
For i = 1 To rowsToRead
temp = .Range("A" & i).Value
Next i
tcEnd = GetTickCount
Application.ScreenUpdating = True
Debug.Print "Time1a: " & tcEnd - tcStart
End With
'***Read individual cells using .Range & screenupdating off & using value2
With Sheet1
Application.ScreenUpdating = False
tcStart = GetTickCount
For i = 1 To rowsToRead
temp = .Range("A" & i).Value2
Next i
tcEnd = GetTickCount
Application.ScreenUpdating = True
Debug.Print "Time1b: " & tcEnd - tcStart
End With
'***Read individual cells using range object
With Sheet1
Set rngobject = .Range("A1:A" & rowsToRead)
tcStart = GetTickCount
For Each rngItem In rngobject
temp = rngItem
Next rngItem
tcEnd = GetTickCount
Debug.Print "Time2: " & tcEnd - tcStart
End With
'***Read individual cells using activecell
With Sheet1
tcStart = GetTickCount
.Range("A1").Select
For i = 1 To rowsToRead
temp = ActiveCell.Offset(i - 1, 0).Value
Next i
tcEnd = GetTickCount
Debug.Print "Time3: " & tcEnd - tcStart
End With
'***Read individual cells using activecell & screenupdating off
With Sheet1
Application.ScreenUpdating = False
tcStart = GetTickCount
.Range("A1").Select
For i = 1 To rowsToRead
temp = ActiveCell.Offset(i - 1, 0).Value
Next i
tcEnd = GetTickCount
Application.ScreenUpdating = True
Debug.Print "Time3a: " & tcEnd - tcStart
End With
'***Read individual cells using array
With Sheet1
tcStart = GetTickCount
rngArray = .Range("A1:A" & rowsToRead).Value
For i = 1 To rowsToRead 'should really use Lbound to Ubound but only example
temp = rngArray(i, 1)
Next i
tcEnd = GetTickCount
Debug.Print "Time4: " & tcEnd - tcStart
End With
End Sub