C# 正则表达式提取字符串中括号里的值

version = Regex.Replace(str, @"(.*()(.*)().*)", "$2"); //小括号()
    
Regex rgx = new Regex(@"(?i)(?<=[)(.*)(?=])");//中括号[]
string tmp = rgx.Match(CvoName).Value;//中括号[]
    
string sheetData = Regex.Match(LinkData, @"{(.*)}", RegexOptions.Singleline).Groups[1].Value;//大括号{}