使用VB.NET掃描文件中的一串字忽略多餘的空格

Question

我正在搜索文件以查找一串單詞。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，但我現在已經發現有些文件可能包含目標短語與字之間不止一個空格差距。

例如我的代碼發現

「one two three」，但未能找到「one two three」

是有辦法，我可以使用正則表達式，或任何其他技術，捕捉到這句話即使之間的距離單詞不止一個空格？

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 

，但我想知道是否有實現這一

Answer 1

您可以創建一個刪除任何雙重空格的函數。

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

你可以在你的短語轉換成正則表達式與\s+每個字之間更有效的方式，和然後檢查相應的文本。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 

請注意，這並不在這句話的開始/結束檢查單詞邊界，所以"This contains someone two threesome"也將匹配。如果你不想要，在正則表達式的兩端添加"\s"。

Answer 3

評論中的代碼將解釋代碼

 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