vbs的字符串操作效率分析总结

如有不对之处，请大家拍拍砖，呵呵
也可以用数组来拼接字符串啦！

'最简单的例子，生成num个重复的str，例如 XString(5,"<br>") '输出: <br><br><br><br><br>
Function XString(num,str)
On Error Resume Next
Dim i,a
Redim a(num-1)
For i=0 To num-1
a(i)=str
Next
XString=Join(a,"")
On Error GoTo 0
End Function


'字符串拼接类公共版
Class clsStrCat
Private aFStrings()
Private iFSPos,iFSLen,iFSIncr
Private Sub Class_Initialize()
On Error Resume Next
iFSIncr = STRCATBUF
If Err Then iFSIncr = 200 : Err.Clear
Reset
On Error GoTo 0
End Sub
Private Sub Class_Terminate()
Erase aFStrings
End Sub
Public Property Let Item(ByRef sData)
If iFSPos > iFSLen Then
iFSLen = iFSPos + iFSIncr
ReDim Preserve aFStrings(iFSLen)
End If
aFStrings(iFSPos) = sData
iFSPos = iFSPos + 1
End Property
Public Default Property Get Item()
Item = Join(aFStrings, "")
End Property
Public Sub Reset()
iFSPos = 0
iFSLen = iFSIncr
ReDim aFStrings(iFSLen)
End Sub
Public Sub Resize(n)
If Not IsNumeric(n) Then Exit Sub
iFSPos = 0
iFSIncr = n
iFSLen = iFSIncr
ReDim aFStrings(iFSLen)
End Sub
Public Property Get Strs()
Strs=aFStrings
End Property
Public Property Get Count()
Count=iFSPos
End Property
Public Property Get IsInit()
If iFSPos=0 Then IsInit=True Else IsInit=False
End Property
End Class