javascript - 在 C# 中匹配表情符号

Question

我正在尝试找到一种从 utf8 文本文件中过滤表情符号的方法。显然有一个可用的 javascript 正则表达式 ( https://raw.githubusercontent.com/mathiasbynens/emoji-regex/master/index.js ) 可用于匹配表情符号。我无法将此正则表达式翻译成 c# 方言(看起来有些差异我不明白)。然后我尝试按照简单的代码来匹配我的文本中的所有非单词和非空格字符(手动检查它们并选择表情符号，然后将它们放入正则表达式中并用空字符串替换它们)。

string input = @"some path\";
            List<char> emojis = new List<char>();
            foreach(FileInfo file in new DirectoryInfo(input).GetFiles("*.txt", SearchOption.AllDirectories))
            {
                MatchCollection matches = Regex.Matches(File.ReadAllText(file.FullName), @"[^\w\s]{1}");
                foreach(Match match in matches)
                {
                    string value = match.Value;
                    foreach(char c in value.ToCharArray())
                    {
                        if(!emojis.Contains(c))
                        {
                            emojis.Add(c);
                        }
                    }
                }
            }
            foreach(char c in emojis)
            {
                File.AppendAllText(@"\\Emojis.txt", c.ToString()+"|");
            }

但是我在#develop 中遇到异常

System.Text.EncoderFallbackException: Unable to translate Unicode character \uD83D at index 0 to specified code page.

显然，将正则表达式匹配的字符转换为字符并不是一个好主意。任何想法我该如何解决这个问题？问候

Answer 1

这是我在 Visual Studio 中运行的代码，它可以毫无问题地执行。

string regex = "(?:0\x20E3|1\x20E3|2\x20E3|3\x20E3|4\x20E3|5\x20E3|6\x20E3|7\x20E3|8\x20E3|9\x20E3|#\x20E3|\\*\x20E3|\xD83C(?:\xDDE6\xD83C(?:\xDDE8|\xDDE9|\xDDEA|\xDDEB|\xDDEC|\xDDEE|\xDDF1|\xDDF2|\xDDF4|\xDDF6|\xDDF7|\xDDF8|\xDDF9|\xDDFA|\xDDFC|\xDDFD|\xDDFF)|\xDDE7\xD83C(?:\xDDE6|\xDDE7|\xDDE9|\xDDEA|\xDDEB|\xDDEC|\xDDED|\xDDEE|\xDDEF|\xDDF1|\xDDF2|\xDDF3|\xDDF4|\xDDF6|\xDDF7|\xDDF8|\xDDF9|\xDDFB|\xDDFC|\xDDFE|\xDDFF)|\xDDE8\xD83C(?:\xDDE6|\xDDE8|\xDDE9|\xDDEB|\xDDEC|\xDDED|\xDDEE|\xDDF0|\xDDF1|\xDDF2|\xDDF3|\xDDF4|\xDDF5|\xDDF7|\xDDFA|\xDDFB|\xDDFC|\xDDFD|\xDDFE|\xDDFF)|\xDDE9\xD83C(?:\xDDEA|\xDDEC|\xDDEF|\xDDF0|\xDDF2|\xDDF4|\xDDFF)|\xDDEA\xD83C(?:\xDDE6|\xDDE8|\xDDEA|\xDDEC|\xDDED|\xDDF7|\xDDF8|\xDDF9|\xDDFA)|\xDDEB\xD83C(?:\xDDEE|\xDDEF|\xDDF0|\xDDF2|\xDDF4|\xDDF7)|\xDDEC\xD83C(?:\xDDE6|\xDDE7|\xDDE9|\xDDEA|\xDDEB|\xDDEC|\xDDED|\xDDEE|\xDDF1|\xDDF2|\xDDF3|\xDDF5|\xDDF6|\xDDF7|\xDDF8|\xDDF9|\xDDFA|\xDDFC|\xDDFE)|\xDDED\xD83C(?:\xDDF0|\xDDF2|\xDDF3|\xDDF7|\xDDF9|\xDDFA)|\xDDEE\xD83C(?:\xDDE8|\xDDE9|\xDDEA|\xDDF1|\xDDF2|\xDDF3|\xDDF4|\xDDF6|\xDDF7|\xDDF8|\xDDF9)|\xDDEF\xD83C(?:\xDDEA|\xDDF2|\xDDF4|\xDDF5)|\xDDF0\xD83C(?:\xDDEA|\xDDEC|\xDDED|\xDDEE|\xDDF2|\xDDF3|\xDDF5|\xDDF7|\xDDFC|\xDDFE|\xDDFF)|\xDDF1\xD83C(?:\xDDE6|\xDDE7|\xDDE8|\xDDEE|\xDDF0|\xDDF7|\xDDF8|\xDDF9|\xDDFA|\xDDFB|\xDDFE)|\xDDF2\xD83C(?:\xDDE6|\xDDE8|\xDDE9|\xDDEA|\xDDEB|\xDDEC|\xDDED|\xDDF0|\xDDF1|\xDDF2|\xDDF3|\xDDF4|\xDDF5|\xDDF6|\xDDF7|\xDDF8|\xDDF9|\xDDFA|\xDDFB|\xDDFC|\xDDFD|\xDDFE|\xDDFF)|\xDDF3\xD83C(?:\xDDE6|\xDDE8|\xDDEA|\xDDEB|\xDDEC|\xDDEE|\xDDF1|\xDDF4|\xDDF5|\xDDF7|\xDDFA|\xDDFF)|\xDDF4\xD83C\xDDF2|\xDDF5\xD83C(?:\xDDE6|\xDDEA|\xDDEB|\xDDEC|\xDDED|\xDDF0|\xDDF1|\xDDF2|\xDDF3|\xDDF7|\xDDF8|\xDDF9|\xDDFC|\xDDFE)|\xDDF6\xD83C\xDDE6|\xDDF7\xD83C(?:\xDDEA|\xDDF4|\xDDF8|\xDDFA|\xDDFC)|\xDDF8\xD83C(?:\xDDE6|\xDDE7|\xDDE8|\xDDE9|\xDDEA|\xDDEC|\xDDED|\xDDEE|\xDDEF|\xDDF0|\xDDF1|\xDDF2|\xDDF3|\xDDF4|\xDDF7|\xDDF8|\xDDF9|\xDDFB|\xDDFD|\xDDFE|\xDDFF)|\xDDF9\xD83C(?:\xDDE6|\xDDE8|\xDDE9|\xDDEB|\xDDEC|\xDDED|\xDDEF|\xDDF0|\xDDF1|\xDDF2|\xDDF3|\xDDF4|\xDDF7|\xDDF9|\xDDFB|\xDDFC|\xDDFF)|\xDDFA\xD83C(?:\xDDE6|\xDDEC|\xDDF2|\xDDF8|\xDDFE|\xDDFF)|\xDDFB\xD83C(?:\xDDE6|\xDDE8|\xDDEA|\xDDEC|\xDDEE|\xDDF3|\xDDFA)|\xDDFC\xD83C(?:\xDDEB|\xDDF8)|\xDDFD\xD83C\xDDF0|\xDDFE\xD83C(?:\xDDEA|\xDDF9)|\xDDFF\xD83C(?:\xDDE6|\xDDF2|\xDDFC)))|[\xA9\xAE\x203C\x2049\x2122\x2139\x2194-\x2199\x21A9\x21AA\x231A\x231B\x2328\x23CF\x23E9-\x23F3\x23F8-\x23FA\x24C2\x25AA\x25AB\x25B6\x25C0\x25FB-\x25FE\x2600-\x2604\x260E\x2611\x2614\x2615\x2618\x261D\x2620\x2622\x2623\x2626\x262A\x262E\x262F\x2638-\x263A\x2648-\x2653\x2660\x2663\x2665\x2666\x2668\x267B\x267F\x2692-\x2694\x2696\x2697\x2699\x269B\x269C\x26A0\x26A1\x26AA\x26AB\x26B0\x26B1\x26BD\x26BE\x26C4\x26C5\x26C8\x26CE\x26CF\x26D1\x26D3\x26D4\x26E9\x26EA\x26F0-\x26F5\x26F7-\x26FA\x26FD\x2702\x2705\x2708-\x270D\x270F\x2712\x2714\x2716\x271D\x2721\x2728\x2733\x2734\x2744\x2747\x274C\x274E\x2753-\x2755\x2757\x2763\x2764\x2795-\x2797\x27A1\x27B0\x27BF\x2934\x2935\x2B05-\x2B07\x2B1B\x2B1C\x2B50\x2B55\x3030\x303D\x3297\x3299]|\xD83C[\xDC04\xDCCF\xDD70\xDD71\xDD7E\xDD7F\xDD8E\xDD91-\xDD9A\xDE01\xDE02\xDE1A\xDE2F\xDE32-\xDE3A\xDE50\xDE51\xDF00-\xDF21\xDF24-\xDF93\xDF96\xDF97\xDF99-\xDF9B\xDF9E-\xDFF0\xDFF3-\xDFF5\xDFF7-\xDFFF]|\xD83D[\xDC00-\xDCFD\xDCFF-\xDD3D\xDD49-\xDD4E\xDD50-\xDD67\xDD6F\xDD70\xDD73-\xDD79\xDD87\xDD8A-\xDD8D\xDD90\xDD95\xDD96\xDDA5\xDDA8\xDDB1\xDDB2\xDDBC\xDDC2-\xDDC4\xDDD1-\xDDD3\xDDDC-\xDDDE\xDDE1\xDDE3\xDDEF\xDDF3\xDDFA-\xDE4F\xDE80-\xDEC5\xDECB-\xDED0\xDEE0-\xDEE5\xDEE9\xDEEB\xDEEC\xDEF0\xDEF3]|\xD83E[\xDD10-\xDD18\xDD80-\xDD84\xDDC0]";
string input = "aedfvwefervsreA";
var result = Regex.Match(input, regex);

我没有测试字符串来查看它是否产生了正确的结果，但这应该是 C# 中 Javascript 模式的一对一表示。