如何用VBA与RegExp保留CRLF提取两个日期字符串间文本

问题场景 #

文档内容示例：

5/1/2023
blah
blah
blah

4/1/2023
jabber
jabber
jabber

预期提取两个日期之间的内容（保留换行）：

blah
blah
blah

但实际提取结果丢失了所有换行：

blahblahblah

用户原VBA代码 #

Function getLastNote()
'extracts content between two date strings. The result should be the latest note entry
Dim regEx As Object, matchCollection As Object, extractedString As String

Set regEx = CreateObject("VBScript.RegExp")

With regEx
  .IgnoreCase = True
  .Global = False    ' Only look for 1 match; False is actually the default.
  .Pattern = "\d{1,2}\/\d{1,2}\/\d{4}((.|\n)*?)\d{1,2}\/\d{1,2}\/\d\d\d\d"
End With

Set matchCollection = regEx.Execute(ActiveDocument.Content.text)
If matchCollection.Count > 0 Then
    ' Extract the first submatch's (capture group's) value -
    getLastNote = matchCollection(0).submatches(0)
Else
    getLastNote = ActiveDocument.Content 'there's no match so return the text of the doc.
End If
End Function

问题原因 #

1. Word文档的文本中，段落换行是段落标记（对应VBA的vbCr，正则里为\r），而非普通的\n，原正则里的\n无法匹配Word的换行符。
2. (.|\n)的写法在VBScript正则中不能可靠匹配所有换行场景，且效率较低。
3. Else分支直接返回ActiveDocument.Content对象而非文本内容，存在逻辑问题。

解决方案 #

修改正则表达式，用[\s\S]匹配任意字符（包括换行），同时修正Else分支的返回值：

Function getLastNote()
'extracts content between two date strings. The result should be the latest note entry
Dim regEx As Object, matchCollection As Object, extractedString As String

Set regEx = CreateObject("VBScript.RegExp")

With regEx
  .IgnoreCase = True
  .Global = False    ' Only look for 1 match; False is actually the default.
  .Pattern = "\d{1,2}\/\d{1,2}\/\d{4}([\s\S]*?)\d{1,2}\/\d{1,2}\/\d{4}"
End With

Set matchCollection = regEx.Execute(ActiveDocument.Content.Text)
If matchCollection.Count > 0 Then
    ' Extract the first submatch's (capture group's) value -
    getLastNote = matchCollection(0).submatches(0)
Else
    getLastNote = ActiveDocument.Content.Text '返回文档文本而非对象
End If
End Function

修改说明 #

• [\s\S]*?：\s匹配任意空白字符（包括Word的段落标记\r），\S匹配非空白字符，组合后能匹配所有字符，确保包含换行的内容被完整捕获。
• 修正Else分支返回ActiveDocument.Content.Text，保证无论是否匹配成功，返回的都是文本格式内容。

内容的提问来源于stack exchange，提问作者Dirigo