How do I reverse individual words in a string in VBA? - vba

Question

I've managed to reverse the string as a whole using the code below:
Dim str As Variant
Dim i As Integer, strLen As Integer
Dim NewStr As String
str = "VBA is amazing"
strLen = Len(str)
NewStr = ""
For i = 1 To strLen
NewStr = NewStr & Mid(str, strLen - (i - 1), 1)
Next i
MsgBox (NewStr)
The outcome is: gnizama si ABV, but I want it to be: ABV si gnizama
Goal is not to use Split or StrReverse.

Answer 1

Goal is not to use Split or StrReverse.
But those are what to use:
Dim Straight As String
Dim Reversed As String
Dim Index As Long
Dim Words() As String
Straight = "VBA is amazing"
Words = Split(Straight)
For Index = LBound(Words) To UBound(Words)
Words(Index) = StrReverse(Words(Index))
Next
Reversed = Join(Words)
Debug.Print Reversed
' ABV si gnizama
If not, you must either roll your own substitutes or run a double loop indentifying spaces and, between these, collect and reverse the words. Slow, but doable.

Answer 2

Solution without Split or StrReverse:
Sub RevWords(Optional str As String = "VBA is amazing")
' RegExp: need to switch on «Microsoft VBScript Regular Expression 5.5» in menu «Tools/References»
Dim RegEx As New RegExp
Dim res As Object, revStr As String, i As Integer, s As Variant
With RegEx
.Global = True
.Pattern = "([^ ]+)"
Set res = .Execute(str)
End With
For Each s In res
e = Len(s)
Do While e > 0
revStr = revStr & Mid(s, e, 1)
e = e - 1
Loop
revStr = revStr & " "
Next
Debug.Print str & " >> " & Trim(revStr)
End Sub
' output: VBA is amazing >> ABV si gnizama

Answer 3

Try this:
Function CustomReverse(inputString As String) As String
Dim wordSeparator As String, reversedString As String
Dim i As Integer, j As Integer, k As Integer, vector As Integer
reversedString = inputString
wordSeparator = " "
i = 0
j = 1
Do
i = InStr(i + 1, inputString, wordSeparator, vbTextCompare)
If i = 0 Then i = Len(inputString) + 1
For k = j To i - 1
If Mid(reversedString, k, 1) = wordSeparator Then Exit For
vector = i - k - 1
Mid(reversedString, k, 1) = Mid(inputString, j + vector, 1)
Next
j = i + 1
Loop While i > 0 And j < Len(inputString)
CustomReverse = reversedString
End Function
Usage:
Sub Test()
Debug.Print CustomReverse("VBA is amazing")
'prints: "ABV si gnizama"
End Sub

Answer 4

Not sure why you don't want to use Split and StrReverse. The implementation is easy:
Sub Test()
Dim s As String
Dim words() As String
Dim i As Long
Dim word As Variant
s = "VBA is amazing"
words = Split(s, " ")
i = LBound(words, 1)
For Each word In words
words(i) = StrReverse(word)
i = i + 1
Next word
MsgBox Join(words, " ")
End Sub
If, for whatever reason, you cannot use Split or StrReverse then you need something like this:
Sub Test2()
Const SPACE As String = " "
Dim lastSpace As Long
Dim nextSpace As Long
Dim s As String
Dim word As String
Dim newStr As String
s = "VBA is amazing"
nextSpace = InStr(1, s, SPACE)
If nextSpace = 0 Then
newStr = ReverseWord(s)
Else
Do While nextSpace > 0
word = Mid$(s, lastSpace + 1, nextSpace - lastSpace - 1)
newStr = newStr & ReverseWord(word) & SPACE
lastSpace = nextSpace
nextSpace = InStr(nextSpace + 1, s, SPACE)
Loop
word = Right$(s, Len(s) - lastSpace)
newStr = newStr & ReverseWord(word)
End If
MsgBox newStr
End Sub
Private Function ReverseWord(ByVal word As String) As String
Dim i As Long
Dim res As String
For i = Len(word) To 1 Step -1
res = res & Mid$(word, i, 1)
Next i
ReverseWord = res
End Function
EDIT #1
The ReverseWord method can be optimized:
Private Function ReverseWord(ByVal word As String) As String
Dim i1 As Long: i1 = 1
Dim i2 As Long: i2 = Len(word)
Dim c As String
Do While i1 < i2
c = Mid$(word, i1, 1)
Mid$(word, i1, 1) = Mid$(word, i2, 1)
Mid$(word, i2, 1) = c
i1 = i1 + 1
i2 = i2 - 1
Loop
ReverseWord = word
End Function

Answer 5

other solution from me
Sub test()
Dim str As Variant
Dim i As Integer, strLen As Integer, iSp As Integer, n As Integer, f As Integer
Dim NewStr As String
Dim wordPart() As String
f = 0
n = 1
str = "VBA is amazing"
strLen = Len(str)
NewStr = ""
iSp = spacesCounter(str) + 1
ReDim wordPart(iSp)
For i = 1 To strLen
If Mid(str, i, 1) = " " Then
If n = 1 Then
wordPart(n) = Mid(str, 1, i - 1)
f = i + 1
n = n + 1
Else
wordPart(n) = Mid(str, f, (i) - f)
f = i + 1
n = n + 1
End If
ElseIf i = strLen Then
wordPart(n) = Mid(str, f)
End If
Next i
For i = 1 To iSp
MsgBox (wordPart(i))
For j = 1 To Len(wordPart(i))
If i <> 1 And j = 1 Then NewStr = NewStr & " "
NewStr = NewStr & Mid(wordPart(i), Len(wordPart(i)) - (j - 1), 1)
Next j
Next i
MsgBox (NewStr)
End Sub

Answer 6

Try,
Sub test()
Dim strL As Variant
Dim i As Integer, strLen As Integer
Dim NewStr As String
Dim s As String, s1 As String
strL = "VBA is amazing"
strLen = Len(strL)
NewStr = ""
For i = 1 To strLen
s = Mid(strL, i, 1)
If s = " " Then
NewStr = NewStr & s1 & s
s1 = ""
Else
s1 = s & s1
End If
Next i
NewStr = NewStr & s1
MsgBox (NewStr)
End Sub