c# - 正则表达式平衡组

Question

我正在尝试匹配字符串中的平衡大括号 ({})。例如，我想平衡以下内容：

if (a == 2)
{
  doSomething();
  { 
     int x = 10;
  }
}

// this is a comment

while (a <= b){
  print(a++);
} 

我从 MSDN 想出了这个正则表达式，但效果不佳。我想提取 {} 的多个嵌套匹配集。我只对父匹配感兴趣

   "[^{}]*" +
   "(" + 
   "((?'Open'{)[^{}]*)+" +
   "((?'Close-Open'})[^{}]*)+" +
   ")*" +
   "(?(Open)(?!))";

Answer 1

你很接近。

改编自这个问题的第二个答案（我将其用作我的规范“在 C#/.NET 正则表达式引擎中平衡 xxx”答案，如果它对您有帮助，请投票支持它！它过去曾帮助过我）：

var r = new Regex(@"
[^{}]*                  # any non brace stuff.
\{(                     # First '{' + capturing bracket
    (?:                 
    [^{}]               # Match all non-braces
    |
    (?<open> \{ )       # Match '{', and capture into 'open'
    |
    (?<-open> \} )      # Match '}', and delete the 'open' capture
    )+                  # Change to * if you want to allow {}
    (?(open)(?!))       # Fails if 'open' stack isn't empty!
)\}                     # Last '}' + close capturing bracket
"; RegexOptions.IgnoreWhitespace);