words.bas

加入一个用VB编写CGI的VB源程序。（你需要在Win98上首先安装20Personal WebServer

      If pointer > lSource Then Exit Do        'beyond end of sSource
      WordIndex = pointer                      'position of word
      Exit Do                                  'word found, done
   End If
  
   pos = InStr(pointer, sSource, SP)           'find next space
   If pos = 0 Then Exit Do                     'word not found
   x = x + 1                                   'increment word counter
   pointer = pos + 1
Loop

Exit Function
strIndex:
sTarget = CStr(vTarget)
lTarget = Len(sTarget)
If lTarget = 0 Then Exit Function              'nothing to count

'find byte position of sTarget (string)
pointer = 1
Do
   pos = InStr(pointer, sSource, sTarget)
   If pos = 0 Then Exit Do
   If Mid$(sSource, pos + lTarget, 1) = SP _
   Or pos + lTarget > lSource Then
      If pos = 1 Then Exit Do
      If Mid$(sSource, pos - 1, 1) = SP Then Exit Do
   End If
   pointer = pos + lTarget
Loop

WordIndex = pos

End Function

Public Function WordLength(ByVal sSource As String, _
                                       n As Long) As Long
'=========================================================
' Wordlength returns the length of the nth word in sSource
' Usage:
'    WordLength("red blue green", 2)    4
'=========================================================
Const SP    As String = " "
Dim lSource As Long   'length of sSource
Dim pointer As Long   'start parameter Instr()
Dim pos     As Long   'position of target with InStr()
Dim x       As Long   'word count
Dim lEnd    As Long   'position of trailing word delimiter

sSource = CSpace(sSource)
lSource = Len(sSource)

'find the nth word
x = 1
pointer = 1

Do
   Do While Mid$(sSource, pointer, 1) = SP     'skip consecutive spaces
      pointer = pointer + 1
   Loop
   If x = n Then                               'the target word-number
      lEnd = InStr(pointer, sSource, SP)       'pos of space at end of word
      If lEnd = 0 Then lEnd = lSource + 1      '   or if its the last word
      WordLength = lEnd - pointer
      Exit Do                                  'word found, done
   End If
  
   pos = InStr(pointer, sSource, SP)           'find next space
   If pos = 0 Then Exit Do                     'word not found
   x = x + 1                                   'increment word counter
  
   pointer = pos + 1                           'start of next word
Loop

End Function

Public Function DelWord(ByVal sSource As String, _
                                    n As Long, _
                      Optional vWords As Variant) As String
'===========================================================
' DelWord deletes from sSource, starting with the
' nth word for a length of vWords words.
' If vWords is omitted, all words from the nth word on are
' deleted.
' Usage:
'   DelWord("now is not the time", 3)     "now is"
'   DelWord("now is not the time", 3, 1)  "now is the time"
'===========================================================
Const SP    As String = " "
Dim lWords  As Long    'length of sTarget
Dim lSource As Long    'length of sSource
Dim pointer As Long    'start parameter of InStr()
Dim pos     As Long    'position of target in InStr()
Dim x       As Long    'word counter
Dim lStart  As Long    'position of word n
Dim lEnd    As Long    'position of space after last word

lSource = Len(sSource)
DelWord = sSource
sSource = CSpace(sSource)
If IsMissing(vWords) Then
   lWords = -1
ElseIf IsNumeric(vWords) Then
   lWords = CLng(vWords)
Else
   Exit Function
End If

If n = 0 Or lWords = 0 Then Exit Function      'nothing to delete

'find position of n
x = 1
pointer = 1

Do
   Do While Mid$(sSource, pointer, 1) = SP     'skip consecutive spaces
      pointer = pointer + 1
   Loop
   If x = n Then                               'the target word-number
      lStart = pointer
      If lWords < 0 Then Exit Do
   End If
   
   If lWords > 0 Then                          'lWords was provided
      If x = n + lWords - 1 Then               'find pos of last word
         lEnd = InStr(pointer, sSource, SP)    'pos of space at end of word
         Exit Do                               'word found, done
      End If
   End If
   
   pos = InStr(pointer, sSource, SP)           'find next space
   If pos = 0 Then Exit Do                     'word not found
   x = x + 1                                   'increment word counter
  
   pointer = pos + 1                           'start of next word
Loop
If lStart = 0 Then Exit Function
If lEnd = 0 Then
   DelWord = Trim$(Left$(sSource, lStart - 1))
Else
   DelWord = Trim$(Left$(sSource, lStart - 1) & Mid$(sSource, lEnd + 1))
End If
End Function

Public Function MidWord(ByVal sSource As String, _
                                    n As Long, _
                      Optional vWords As Variant) As String
'===========================================================
' MidWord returns a substring sSource, starting with the
' nth word for a length of vWords words.
' If vWords is omitted, all words from the nth word on are
' returned.
' Usage:
'   MidWord("now is not the time", 3)     "not the time"
'   MidWord("now is not the time", 3, 2)  "not the"
'===========================================================
Const SP    As String = " "
Dim lWords  As Long    'vWords converted to long
Dim lSource As Long    'length of sSource
Dim pointer As Long    'start parameter of InStr()
Dim pos     As Long    'position of target in InStr()
Dim x       As Long    'word counter
Dim lStart  As Long    'position of word n
Dim lEnd    As Long    'position of space after last word

lSource = Len(sSource)
sSource = CSpace(sSource)
If IsMissing(vWords) Then
   lWords = -1
ElseIf IsNumeric(vWords) Then
   lWords = CLng(vWords)
Else
   Exit Function
End If

If n = 0 Or lWords = 0 Then Exit Function              'nothing to delete

'find position of n
x = 1
pointer = 1

Do
   Do While Mid$(sSource, pointer, 1) = SP     'skip consecutive spaces
      pointer = pointer + 1
   Loop
   If x = n Then                               'the target word-number
      lStart = pointer
      If lWords < 0 Then Exit Do               'include rest of sSource
   End If
   
   If lWords > 0 Then                          'lWords was provided
      If x = n + lWords - 1 Then               'find pos of last word
         lEnd = InStr(pointer, sSource, SP)    'pos of space at end of word
         Exit Do                               'word found, done
      End If
   End If
   
   pos = InStr(pointer, sSource, SP)           'find next space
   If pos = 0 Then Exit Do                     'word not found
   x = x + 1                                   'increment word counter
  
   pointer = pos + 1                           'start of next word
Loop
If lStart = 0 Then Exit Function
If lEnd = 0 Then
   MidWord = Trim$(Mid$(sSource, lStart))
Else
   MidWord = Trim$(Mid$(sSource, lStart, lEnd - lStart))
End If
End Function

Public Function CSpace(sSource As String) As String
'==================================================
'CSpace converts blank characters
'(ascii: 9,10,13,160) to space (32)
'
'  cSpace("a" & vbTab   & "b")  "a b"
'  cSpace("a" & vbCrlf  & "b")  "a  b"
'==================================================
Dim pointer   As Long
Dim pos       As Long
Dim x         As Long
Dim iSpace(3) As Integer

' define blank characters
iSpace(0) = 9    'Horizontal Tab
iSpace(1) = 10   'Line Feed
iSpace(2) = 13   'Carriage Return
iSpace(3) = 160  'Hard Space

CSpace = sSource
For x = 0 To UBound(iSpace) ' replace all blank characters with space
   pointer = 1
   Do
      pos = InStr(pointer, CSpace, Chr$(iSpace(x)))
      If pos = 0 Then Exit Do
      Mid$(CSpace, pos, 1) = " "
      pointer = pos + 1
   Loop
Next x

End Function