c# - 从前面带有分隔符的文本中删除单词(使用正则表达式)

Question

我需要从文本中删除旁边带有分隔符的单词。我已经删除了单词，但我不知道如何同时删除分隔符。有什么建议吗？
目前我有:

static void Main(string[] args)
        {
            Program p = new Program();
            string text = "";
            text = p.ReadText("Duomenys.txt", text);
            string[] wordsToDelete = { "Hello", "Thanks", "kinda" };
            char[] separators = { ' ', '.', ',', '!', '?', ':', ';', '(', ')', '\t' };
            p.DeleteWordsFromText(text, wordsToDelete, separators);
        }

        public string ReadText(string file, string text)
        {     
            text = File.ReadAllText(file);           
            return text;
        }

        public void DeleteWordsFromText(string text, string[] wordsToDelete, char[] separators)
        {
            Console.WriteLine(text);
            for (int i = 0; i < wordsToDelete.Length; i++)
            {
                text = Regex.Replace(text, wordsToDelete[i], String.Empty);
            }
            Console.WriteLine("-------------------------------------------");
            Console.WriteLine(text);
        }

结果应该是:

how are you?
I am  good.

我有:

, how are you?
, I am . good.

Duomenys.txt

Hello, how are you? 
Thanks, I am kinda. good. 

Answer 1

你可以像这样构建一个正则表达式

\b(?:Hello|Thanks|kinda)\b[ .,!?:;()    ]*

其中 \b(?:Hello|Thanks|kinda)\b 将匹配任何要删除的单词作为整个单词和 [ .,!?:;() ]* 将在要删除的单词之后匹配所有分隔符 0 次或多次。

C# solution :

char[] separators = { ' ', '.', ',', '!', '?', ':', ';', '(', ')', '\t' };
string[] wordsToDelete = { "Hello", "Thanks", "kinda" };
string SepPattern = new String(separators).Replace(@"\", @"\\").Replace("^", @"\^").Replace("-", @"\-").Replace("]", @"\]");
var pattern = $@"\b(?:{string.Join("|", wordsToDelete.Select(Regex.Escape))})\b[{SepPattern}]*";
// => \b(?:Hello|Thanks|kinda)\b[ .,!?:;()  ]*
Regex rx = new Regex(pattern, RegexOptions.Compiled);
// RegexOptions.IgnoreCase can be added to the above flags for case insensitive matching: RegexOptions.IgnoreCase | RegexOptions.Compiled
DeleteWordsFromText("Hello, how are you?", rx);
DeleteWordsFromText("Thanks, I am kinda. good.", rx);

这是 DeleteWordsFromText 方法:

public static void DeleteWordsFromText(string text, Regex p)
{
    Console.WriteLine($"---- {text} ----");
    Console.WriteLine(p.Replace(text, ""));
}

输出:

---- Hello, how are you? ----
how are you?
---- Thanks, I am kinda. good. ----
I am good.

注意事项:

• string SepPattern = new String(分隔符).Replace(@"\", @"\\").Replace("^", @"\^").Replace("-", @"\-").Replace("]", @"\]"); - 它是将在字符类中使用的分隔符模式，因为只有 ^, -, \, ] 字符需要在字符类中转义，只有这些字符被转义
• $@"\b(?:{string.Join("|", wordsToDelete.Select(Regex.Escape))})\b" - 这将从单词构建交替删除并且只会将它们作为整个单词进行匹配。

图案细节

• \b - 单词边界
• (?: - 非捕获组的开始:
  • Hello - Hello 字词
  • | - 或
  • Thanks- 谢谢 word
  • | - 或者
  • kinda- kinda 单词
• ) - 组结束
• \b - 单词边界
• [ .,!?:;() ]* - 字符类中任何 0+ 个字符。

参见 regex demo .