正则表达式平衡组

[zenjj99]

想学习平衡组正则表达式，这种正则式不懂，

这个是我想验证的正则表达式

{if(name == "")}
{elseif(name == "")}
{else}
{/if}

下面的是正则验证字符

{if(name == "1")}
fsc
{elseif(name == "2")}
	{if(name == "1")}
	ds2
	{elseif(name == "3")}
	xk00
	{else}
	25s
	{/if}
{else}
df
{/if}

想用平衡组来写，可是

{elseif(name == "")}
{else}

这2个可有可无，相互嵌套时不知道怎么样写，那位前辈能解决呢？？
谢谢！！

[-过客-]

看你的举例，结束标志{/if}只与{if(name == "")}对应，与{elseif(name == "")}或{else}无关

Regex reg = new Regex(@"(?is){if\(name\s*==(?>{if\(name\s*==(?<o>)|{/if}(?<-o>)|(?:(?!{/?if).)*)*(?(o)(?!)){/if}");
MatchCollection mc = reg.Matches(yourStr);
foreach (Match m in mc)
{
    richTextBox2.Text += m.Value + "\n================\n";
}

[zenjj99]

内部那个嵌套不能提取出来

[zenjj99]

那我如何能分别{elseif(name == "")}或{else}是属于那个{if(name == "")}和{/if} 的呢？

[-过客-]

以下面这个为例，你想要的结果是什么？

{if(name == "1")}
fsc
{elseif(name == "2")}
{if(name == "1")}
ds2
{elseif(name == "3")}
xk00
{else}
25s
{/if}
{else}
df
{/if}

[zenjj99]

能否分成

{if(name == "1")}
fsc
{elseif(name == "2")}
  {if(name == "1")}
  ds2
  {elseif(name == "3")}
  xk00
  {else}
  25s
  {/if}
{else}
df
{/if}

  {if(name == "1")}
  ds2
  {elseif(name == "3")}
  xk00
  {else}
  25s
  {/if}

能分割只和它结构相关体

[-过客-]

在这篇博客的4 平衡组应用范围探讨中我有介绍，这类需求，用正则要加递归来实现
.NET正则基础之——平衡组

//递归方法
private void getNesting(string src, Regex reg, List<string> list)
{
    MatchCollection mc = reg.Matches(src);
    foreach (Match m in mc)
    {
        list.Add(m.Value);
        src = m.Value.Remove(m.Value.Length - 1, 1);
        if (reg.IsMatch(src))
        {
            getNesting(src, reg, list);
        }
    }
}            
//调用
string test = @"{if(name == ""1"")}
fsc
{elseif(name == ""2"")}
  {if(name == ""1"")}
  ds2
  {elseif(name == ""3"")}
  xk00
  {else}
  25s
  {/if}
{else}
df
{/if}";
List<string> list = new List<string>();
Regex reg = new Regex(@"(?is){if\(name\s*==(?>{if\(name\s*==(?<o>)|{/if}(?<-o>)|(?:(?!{/?if).)*)*(?(o)(?!)){/if}");
getNesting(test, reg, list);
foreach (string s in list)
{
    richTextBox2.Text += s + "\n====================\n";
}

[zenjj99]

3Q，过客前辈就是厉害，^_^