topical media & game development
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

talk show tell print

basic-regex-20-Lookaheads.htm / htm



  <html>
  <head>
  <title>Positive and Negative Lookahead</title>
  <script language="vbscript" type="text/vbscript">
  Function MatchLookaheads
  Dim myRegExp, TestName, Match, Matches, displayString
  displayString = ""
  Set myRegExp = new RegExp
  myRegExp.Pattern = "the(?=atre)" 'matches, for example, the in theatre
  myRegExp.IgnoreCase = True
  myRegExp.Global = True
  TestString = InputBox("Enter characters and numbers in the text box below.")
  Set Matches = myRegexp.Execute(TestString)
  displayString = displayString & "MATCH ATTEMPT 1: 'the' in 'theatre'" & VBCrLf
    For Each Match in Matches
      displayString = displayString & "Match found at position " & Match.FirstIndex & "."
      displayString = displayString & "The match value is '" & Match.Value & "'." & VBCrLf
    Next
  displayString = displayString & VBCrLf & VBCrLf
  'Begin a new match which produces a new Match collection.
  myRegExp.Pattern = "the(?!atre)" 'matches the NOT in theatre
  Set Matches = myRegexp.Execute(TestString)
  displayString = displayString & "MATCH ATTEMPT 2: 'the' not in 'theatre'" & VBCrLf
    For Each Match in Matches
      displayString = displayString & "Match found at position " & Match.FirstIndex & "."
      displayString = displayString & "The match value is '" & Match.Value & "'." & VBCrLf
    Next
    MsgBox displayString
  End Function
  
  </script>
  </head>
  <body onload="MatchLookaheads">
  
  </body>
  </html>
[] readme course(s) preface I 1 2 II 3 4 III 5 6 7 IV 8 9 10 V 11 12 afterthought(s) appendix reference(s) example(s) resource(s) _

(C) Æliens 20/2/2008

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