最后一个C#正则问题了,搞了半天搞不对啊。
string str1 = "1";
string str2 = "2";
string str3 = "3";
string str4 = "4";
string str = "1X23Y4";
string pattern = string.Format(@"(?<={0})(((?!{1}).)*)(?={1}{2}(((?!{3}).)*){3})", str1, str2, str3, str4);
str = Regex.Replace(str, pattern, "$3");
如果2-3之间有未知的字符串,这个正则该怎么改改???