asp 数组插入元素的速度问题

在第5个位置插入元素代码如下：

Dim arr(), num
...
num = UBound(arr)
ReDim Preserve arr(num + 1)
For i = num + 1 To 5 + 1 Step -1
    arr(i) = arr(i - 1)
Next
arr(5) = "new value"

与

Function ArrayCopy(src, srcpos, dest, destpos, clength)
    Do While clength > 0
        dest(destpos + (clength - 1)) = src(srcpos + (clength - 1))
        clength = clength - 1
    Loop
End Function

Dim arr(10), b
...
num = UBound(arr)
b = Array(num + 1)
Call ArrayCopy(a, 0, b, 0, 4)
Call ArrayCopy(a, 5, b, 6, 6)
b(5) = "new value"
arr = b

哪一个效率比较高呢？？？

---

Dim arr(), num
...
num = UBound(arr)
ReDim Preserve arr(num + 1)
For i = num + 1 To 5 + 1 Step -1
    arr(i) = arr(i - 1)
Next
arr(5) = "new value"
这个高吧

---

第一个。