c# - 正则表达式全局替换为组

Question

我四处寻找如何在涉及组的 C# 中实现正则表达式全局替换的示例，但一无所获。所以我自己写了。谁能提出更好的方法来做到这一点？

static void Main(string[] args)
{
    Regex re = new Regex(@"word(\d)-(\d)");
    string input = "start word1-2 filler word3-4 end";
    StringBuilder output = new StringBuilder();
    int beg = 0;
    Match match = re.Match(input);
    while (match.Success)
    {
        // get string before match
        output.Append(input.Substring(beg, match.Index - beg));

        // replace "wordX-Y" with "wdX-Y"
        string repl = "wd" + match.Groups[1].Value + "-" + match.Groups[2].Value;
        // get replacement string
        output.Append(re.Replace(input.Substring(match.Index, match.Length), repl));

        // get string after match
        Match nmatch = match.NextMatch();
        int end = (nmatch.Success) ? nmatch.Index : input.Length;
        output.Append(input.Substring(match.Index + match.Length, end - (match.Index + match.Length)));

        beg = end;
        match = nmatch;
    }
    if (beg == 0)
        output.Append(input);
}

Answer 1

您根本不需要执行任何逻辑，可以使用替换字符串中的组引用来完成替换:

string output = Regex.Replace(input, @"word(\d)-(\d)", "wd$1-$2");