c# - 正则表达式模式与某些节目标题不匹配

Question

使用 C# 正则表达式匹配并返回从字符串解析的数据会返回不可靠的结果。

我使用的模式如下:

Regex r=new Regex( 
      @"(.*?)S?(\d{1,2})E?(\d{1,2})(.*)|(.*?)S?(\d{1,2})E?(\d{1,2})",
      RegexOptions.IgnoreCase
);

以下是几个失败的测试用例

---

Ellen 2015.05.22 Joseph Gordon Levitt [REPOST]
The Soup 2015.05.22 [mp4]
Big Brother UK Live From The House (May 22, 2015)

应该返回

• 显示姓名(例如，Ellen)
• 日期(例如，2015.05.22)
• 额外信息(例如，Joseph Gordon Levitt [REPOST])

---

Alaskan Bush People S02 Wild Times Special

应该返回

• 显示名称(例如，Alaskan Bush People)
• 季节(例如，02)
• 额外信息(例如，Wild Times Special)

---

500 Questions S01E03

应该返回

• 显示名称(例如，500 个问题)
• 季节(例如，01)
• 剧集(例如，03)

工作并返回正确数据的示例

Boyster S01E13 – E14
Mysteries at the Museum S08E08
Mysteries at the National Parks S01E07 – E08
The Last Days Of… S01E06
Born Naughty? S01E02
Have I Got News For You S49E07

看起来，模式忽略 S 和 E(如果未找到)，然后使用第一组匹配数字填充该槽。

很明显，此模式需要做更多工作才能处理上述可变字符串。非常感谢您在此问题上的协助。

Answer 1

分而治之

您试图用一个简单的表达式解析太多内容。那不会很好地工作。在这种情况下，最好的方法是将问题分成更小的问题，然后分别解决每个问题。然后，我们可以稍后将所有内容组合成一个模式。

让我们为要提取的数据编写一些模式。

• 季/集:

  S\d+(?:E\d+(?:\s*\p{Pd}\s*E\d+)?)?
  

  我使用 \p{Pd} 而不是 - 来适应任何破折号类型。

• 日期:

  \d{4}\.\d{1,2}\.\d{1,2}
  

  或者...

  (?i:January|February|March|April|May|June|July|August|September|October|November|December)
  \s*\d{1,2},\s*\d{4}
  

• 为额外信息写一个简单的模式:

  .*?
  

  (是的，这很普通)

• 我们还可以像这样检测显示格式:

  \[.*?\]
  

• 您可以根据需要添加其他部分。

现在，我们可以将所有内容放入一个模式中，使用组名来提取数据:

^\s*
(?<name>.*?)
(?<info> \s+ (?:
    (?<episode>S\d+(?:E\d+(?:\s*\p{Pd}\s*E\d+)?)?)
    |
    (?<date>\d{4}\.\d{1,2}\.\d{1,2})
    |
    \(?(?<date>(?i:January|February|March|April|May|June|July|August|September|October|November|December)\s*\d{1,2},\s*\d{4})\)?
    |
    \[(?<format>.*?)\]
    |
    (?<extra>(?(info)|(?!)).*?)
))*
\s*$

只需忽略 info 组(它用于 extra 中的条件，这样 extra 就不会消耗应该属于的部分节目名称)。你可以获得多个 extra 信息，所以只需将它们连接起来，在每个部分之间留一个空格。

示例代码:

var inputData = new[]
{
    "Boyster S01E13 – E14",
    "Mysteries at the Museum S08E08",
    "Mysteries at the National Parks S01E07 – E08",
    "The Last Days Of… S01E06",
    "Born Naughty? S01E02",
    "Have I Got News For You S49E07",
    "Ellen 2015.05.22 Joseph Gordon Levitt [REPOST]",
    "The Soup 2015.05.22 [mp4]",
    "Big Brother UK Live From The House (May 22, 2015)",
    "Alaskan Bush People S02 Wild Times Special",
    "500 Questions S01E03"
};

var re = new Regex(@"
    ^\s*
    (?<name>.*?)
    (?<info> \s+ (?:
        (?<episode>S\d+(?:E\d+(?:\s*\p{Pd}\s*E\d+)?)?)
        |
        (?<date>\d{4}\.\d{1,2}\.\d{1,2})
        |
        \(?(?<date>(?i:January|February|March|April|May|June|July|August|September|October|November|December)\s*\d{1,2},\s*\d{4})\)?
        |
        \[(?<format>.*?)\]
        |
        (?<extra>(?(info)|(?!)).*?)
    ))*
    \s*$
", RegexOptions.IgnorePatternWhitespace);

foreach (var input in inputData)
{
    Console.WriteLine();
    Console.WriteLine("--- {0} ---", input);

    var match = re.Match(input);
    if (!match.Success)
    {
        Console.WriteLine("FAIL");
        continue;
    }

    foreach (var groupName in re.GetGroupNames())
    {
        if (groupName == "0" || groupName == "info")
            continue;

        var group = match.Groups[groupName];
        if (!group.Success)
            continue;

        foreach (Capture capture in group.Captures)
            Console.WriteLine("{0}: '{1}'", groupName, capture.Value);
    }
}

这个的输出是...

--- Boyster S01E13 - E14 ---
name: 'Boyster'
episode: 'S01E13 - E14'

--- Mysteries at the Museum S08E08 ---
name: 'Mysteries at the Museum'
episode: 'S08E08'

--- Mysteries at the National Parks S01E07 - E08 ---
name: 'Mysteries at the National Parks'
episode: 'S01E07 - E08'

--- The Last Days Ofâ?¦ S01E06 ---
name: 'The Last Days Ofâ?¦'
episode: 'S01E06'

--- Born Naughty? S01E02 ---
name: 'Born Naughty?'
episode: 'S01E02'

--- Have I Got News For You S49E07 ---
name: 'Have I Got News For You'
episode: 'S49E07'

--- Ellen 2015.05.22 Joseph Gordon Levitt [REPOST] ---
name: 'Ellen'
date: '2015.05.22'
format: 'REPOST'
extra: 'Joseph'
extra: 'Gordon'
extra: 'Levitt'

--- The Soup 2015.05.22 [mp4] ---
name: 'The Soup'
date: '2015.05.22'
format: 'mp4'

--- Big Brother UK Live From The House (May 22, 2015) ---
name: 'Big Brother UK Live From The House'
date: 'May 22, 2015'

--- Alaskan Bush People S02 Wild Times Special ---
name: 'Alaskan Bush People'
episode: 'S02'
extra: 'Wild'
extra: 'Times'
extra: 'Special'

--- 500 Questions S01E03 ---
name: '500 Questions'
episode: 'S01E03'