使用VB.NET扫描文件中的一串字忽略多余的空格

Question

我正在搜索文件以查找一串单词。例如“一二三”。我一直在使用：

Dim text As String = File.ReadAllText(filepath) 
For each phrase in phrases 
    index = text.IndexOf(phrase, StringComparison.OrdinalIgnoreCase) 
    If index >= 0 Then 
     Exit For 
    End If 
Next 

和它的工作很好，但我现在已经发现有些文件可能包含目标短语与字之间不止一个空格差距。

例如我的代码发现

“one two three”，但未能找到“one two three”

是有办法，我可以使用正则表达式，或任何其他技术，捕捉到这句话即使之间的距离单词不止一个空格？

我知道我可以使用

Dim text As String = File.ReadAllText(filepath) 
For each phrase in phrases 
    text=text.Replace(" "," ") 
    index = text.IndexOf(phrase, StringComparison.OrdinalIgnoreCase) 
    If index >= 0 Then 
     Exit For 
    End If 
Next 

，但我想知道是否有实现这一

Answer 1

您可以创建一个删除任何双重空格的函数。

Option Strict On 
Option Explicit On 
Option Infer Off 
Public Class Form1 
    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load 
     Dim testString As String = "one two three four five  six" 
     Dim excessSpacesGone As String = RemoveExcessSpaces(testString) 
     'one two three four five six 
     Clipboard.SetText(excessSpacesGone) 
     MsgBox(excessSpacesGone) 
    End Sub 
    Function RemoveExcessSpaces(source As String) As String 
     Dim result As String = source 
     Do 
      result = result.Replace(" ", " "c) 
     Loop Until result.IndexOf(" ") = -1 
     Return result 
    End Function 
End Class 

Answer 2

你可以在你的短语转换成正则表达式与\s+每个字之间更有效的方式，和然后检查相应的文本。例如

Dim text = "This contains one Two three" 
Dim phrases = { 
    "one two three" 
} 
' Splits each phrase into words and create the regex from the words. 
For each phrase in phrases.Select(Function(p) String.Join("\s+", p.Split({" "c}, StringSplitOptions.RemoveEmptyEntries))) 
    If Regex.IsMatch(text, phrase, RegexOptions.IgnoreCase) Then 
     Console.WriteLine("Found!") 
     Exit For 
    End If 
Next 

请注意，这并不在这句话的开始/结束检查单词边界，所以"This contains someone two threesome"也将匹配。如果你不想要，在正则表达式的两端添加"\s"。

Answer 3

评论中的代码将解释代码

 Dim inputStr As String = "This contains one  Two three and some  other words" '<--- this be the input from the file 
     inputStr = Regex.Replace(inputStr, "\s{2,}", " ") '<--- Replace extra white spaces if any 
     Dim searchStr As String = "one two three" '<--- be the string to be searched 
     searchStr = Regex.Replace(searchStr, "\s{2,}", " ") '<--- Replace extra white spaces if any 
     If UCase(inputStr).Contains(UCase(searchStr)) Then '<--- check if input contains search string 
      MsgBox("contains") '<-- display message if it contains 
     End If