The following code is a fast way to compose a big string by using Mid$ function instead of using the concatenating operator. The strings concatenated in a loop are often variable. So use S1 to represent general case.
Const AllocFactor = 100000 Dim S As String Dim S1 As String Dim tmp As String Dim i As Long Dim StrLen As Long Dim MaxLen As Long Dim Curpos As Long Dim CurLen As Long MaxLen = AllocFactor S = Space(MaxLen) Curpos = 1 S1 = "abc" For i = 0 To 99999 StrLen = Len(S1) CurLen = Curpos + StrLen - 1 If CurLen > MaxLen Then tmp = S S = Space(MaxLen + AllocFactor) Mid$(S, 1, MaxLen) = tmp MaxLen = MaxLen + AllocFactor End If Mid$(S, Curpos, StrLen) = S1 Curpos = CurLen + 1 Next If CurLen
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