為什么使用整數而不是長？我經常看到Overflow與vba錯誤有關的問題。我的問題是為什么使用integer變量聲明而不是僅僅定義所有數值變量（不包括double等）long？除非您正在執行類似for循環的操作，您可以保證該值不會超過32,767的限制，否則是否會對性能產生影響或其他會導致不使用long？
4 回答
飲歌長嘯
TA貢獻1951條經驗 獲得超3個贊
即使這篇文章已有四年歷史了，我對此感到好奇并進行了一些測試。最重要的是要注意編碼器應該始終將變量聲明為SOMETHING。未申報的變量顯然表現最差（技術上未申報Variant）
Long確實表現最快，所以我不得不認為微軟總是建議使用Long而不是Integer有意義。我猜測也是如此Byte，但大多數程序員都沒有使用它。
64位WINDOWS 10 LAPTOP的結果
使用代碼：
Sub VariableOlymics()'Run this macro as many times as you'd like, with an activesheet ready for data'in cells B2 to D6Dim beginTIME As
Double, trials As Long, i As Long, p As Long
trials = 1000000000
p = 0
beginTIME = Now For i = 1 To trials Call boomBYTE Next i Call Finished(p, Now - beginTIME, CDbl(trials))
p = p + 1
beginTIME = Now For i = 1 To trials Call boomINTEGER Next i Call Finished(p, Now - beginTIME, CDbl(trials))
p = p + 1
beginTIME = Now For i = 1 To trials Call boomLONG Next i Call Finished(p, Now - beginTIME, CDbl(trials))
p = p + 1
beginTIME = Now For i = 1 To trials Call boomDOUBLE Next i Call Finished(p, Now - beginTIME, CDbl(trials))
p = p + 1
beginTIME = Now For i = 1 To trials Call boomUNDECLARED Next i Call Finished(p, Now - beginTIME, CDbl(trials))
p = p + 1End SubPrivate Sub boomBYTE()Dim a As Byte, b As Byte, c As Byte
a = 1
b = 1 + a
c = 1 + b
c = c + 1End SubPrivate Sub boomINTEGER()Dim a As Integer, b As Integer, c As Integer
a = 1
b = 1 + a
c = 1 + b
c = c + 1End SubPrivate Sub boomLONG()Dim a As Long, b As Long, c As Long
a = 1
b = 1 + a
c = 1 + b
c = c + 1End SubPrivate Sub boomDOUBLE()Dim a As Double, b As Double, c As Double
a = 1
b = 1 + a
c = 1 + b
c = c + 1End SubPrivate Sub boomUNDECLARED()
a = 1
b = 1 + a
c = 1 + b
c = c + 1End SubPrivate Sub Finished(i As Long, timeUSED As Double, trials As Double)
With Range("B2").Offset(i, 0)
.Value = .Value + trials .Offset(0, 1).Value = .Offset(0, 1).Value + timeUSED
.Offset(0, 2).FormulaR1C1 = "=ROUND(RC[-1]*3600*24,0)"
End WithEnd Sub添加回答
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