Detecting *all* emojis

Question

Right now I'm using this piece of code :

public static bool ContainsEmoji(this string text) {     Regex rgx = new Regex(@"\p{Cs}");     return rgx.IsMatch(text); } 

And it's being somewhat helpful.

Most of them appear to be detected, but some aren't.

Here's a reference list to help : http://unicode.org/emoji/charts/full-emoji-list.html

All the smiley faces appear to be fine, but these specific emojis do not get caught by the Regex :

1920 U+2614 ☔ umbrella with rain drops

1921 U+26F1 ⛱ umbrella on ground

1922 U+26A1 ⚡ high voltage

1923 U+2744 ❄ snowflake

On the keyboard these are not close to each other, but in the list they are following each other, so I just assumed that there was a point where it would start not working in the emoji list, and it's not really verifying. From 1905 (weather-like emojis), going down, some are caught in the regex, some aren't. There does not seem to be any rule.

I can't afford to just go full ASCII because I need people to enter characters such as cyrillic, but I can't accept emojis specifically. I have no clue how to go forward from here.

I read the MSDN docs about surrogates high/low pairs, but at this stage this is very confusing to me, and I think some push in the right direction would go a long way.

Thank you very much for your time :)

Answer 1

You may use the following regex to match all 4702 emoji characters defined in the Emoji Keyboard/Display Test Data for UTR #51 (Version: 14.0) file:

var EmojiPattern = @"[#*0-9]\uFE0F?\u20E3|©\uFE0F?|[®\u203C\u2049\u2122\u2139\u2194-\u2199\u21A9\u21AA]\uFE0F?|[\u231A\u231B]|[\u2328\u23CF]\uFE0F?|[\u23E9-\u23EC]|[\u23ED-\u23EF]\uFE0F?|\u23F0|[\u23F1\u23F2]\uFE0F?|\u23F3|[\u23F8-\u23FA\u24C2\u25AA\u25AB\u25B6\u25C0\u25FB\u25FC]\uFE0F?|[\u25FD\u25FE]|[\u2600-\u2604\u260E\u2611]\uFE0F?|[\u2614\u2615]|\u2618\uFE0F?|\u261D(?:\uD83C[\uDFFB-\uDFFF]|\uFE0F)?|[\u2620\u2622\u2623\u2626\u262A\u262E\u262F\u2638-\u263A\u2640\u2642]\uFE0F?|[\u2648-\u2653]|[\u265F\u2660\u2663\u2665\u2666\u2668\u267B\u267E]\uFE0F?|\u267F|\u2692\uFE0F?|\u2693|[\u2694-\u2697\u2699\u269B\u269C\u26A0]\uFE0F?|\u26A1|\u26A7\uFE0F?|[\u26AA\u26AB]|[\u26B0\u26B1]\uFE0F?|[\u26BD\u26BE\u26C4\u26C5]|\u26C8\uFE0F?|\u26CE|[\u26CF\u26D1\u26D3]\uFE0F?|\u26D4|\u26E9\uFE0F?|\u26EA|[\u26F0\u26F1]\uFE0F?|[\u26F2\u26F3]|\u26F4\uFE0F?|\u26F5|[\u26F7\u26F8]\uFE0F?|\u26F9(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?|\uFE0F(?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\u26FA\u26FD]|\u2702\uFE0F?|\u2705|[\u2708\u2709]\uFE0F?|[\u270A\u270B](?:\uD83C[\uDFFB-\uDFFF])?|[\u270C\u270D](?:\uD83C[\uDFFB-\uDFFF]|\uFE0F)?|\u270F\uFE0F?|[\u2712\u2714\u2716\u271D\u2721]\uFE0F?|\u2728|[\u2733\u2734\u2744\u2747]\uFE0F?|[\u274C\u274E\u2753-\u2755\u2757]|\u2763\uFE0F?|\u2764(?:\u200D(?:\uD83D\uDD25|\uD83E\uDE79)|\uFE0F(?:\u200D(?:\uD83D\uDD25|\uD83E\uDE79))?)?|[\u2795-\u2797]|\u27A1\uFE0F?|[\u27B0\u27BF]|[\u2934\u2935\u2B05-\u2B07]\uFE0F?|[\u2B1B\u2B1C\u2B50\u2B55]|[\u3030\u303D\u3297\u3299]\uFE0F?|\uD83C(?:[\uDC04\uDCCF]|[\uDD70\uDD71\uDD7E\uDD7F]\uFE0F?|[\uDD8E\uDD91-\uDD9A]|\uDDE6\uD83C[\uDDE8-\uDDEC\uDDEE\uDDF1\uDDF2\uDDF4\uDDF6-\uDDFA\uDDFC\uDDFD\uDDFF]|\uDDE7\uD83C[\uDDE6\uDDE7\uDDE9-\uDDEF\uDDF1-\uDDF4\uDDF6-\uDDF9\uDDFB\uDDFC\uDDFE\uDDFF]|\uDDE8\uD83C[\uDDE6\uDDE8\uDDE9\uDDEB-\uDDEE\uDDF0-\uDDF5\uDDF7\uDDFA-\uDDFF]|\uDDE9\uD83C[\uDDEA\uDDEC\uDDEF\uDDF0\uDDF2\uDDF4\uDDFF]|\uDDEA\uD83C[\uDDE6\uDDE8\uDDEA\uDDEC\uDDED\uDDF7-\uDDFA]|\uDDEB\uD83C[\uDDEE-\uDDF0\uDDF2\uDDF4\uDDF7]|\uDDEC\uD83C[\uDDE6\uDDE7\uDDE9-\uDDEE\uDDF1-\uDDF3\uDDF5-\uDDFA\uDDFC\uDDFE]|\uDDED\uD83C[\uDDF0\uDDF2\uDDF3\uDDF7\uDDF9\uDDFA]|\uDDEE\uD83C[\uDDE8-\uDDEA\uDDF1-\uDDF4\uDDF6-\uDDF9]|\uDDEF\uD83C[\uDDEA\uDDF2\uDDF4\uDDF5]|\uDDF0\uD83C[\uDDEA\uDDEC-\uDDEE\uDDF2\uDDF3\uDDF5\uDDF7\uDDFC\uDDFE\uDDFF]|\uDDF1\uD83C[\uDDE6-\uDDE8\uDDEE\uDDF0\uDDF7-\uDDFB\uDDFE]|\uDDF2\uD83C[\uDDE6\uDDE8-\uDDED\uDDF0-\uDDFF]|\uDDF3\uD83C[\uDDE6\uDDE8\uDDEA-\uDDEC\uDDEE\uDDF1\uDDF4\uDDF5\uDDF7\uDDFA\uDDFF]|\uDDF4\uD83C\uDDF2|\uDDF5\uD83C[\uDDE6\uDDEA-\uDDED\uDDF0-\uDDF3\uDDF7-\uDDF9\uDDFC\uDDFE]|\uDDF6\uD83C\uDDE6|\uDDF7\uD83C[\uDDEA\uDDF4\uDDF8\uDDFA\uDDFC]|\uDDF8\uD83C[\uDDE6-\uDDEA\uDDEC-\uDDF4\uDDF7-\uDDF9\uDDFB\uDDFD-\uDDFF]|\uDDF9\uD83C[\uDDE6\uDDE8\uDDE9\uDDEB-\uDDED\uDDEF-\uDDF4\uDDF7\uDDF9\uDDFB\uDDFC\uDDFF]|\uDDFA\uD83C[\uDDE6\uDDEC\uDDF2\uDDF3\uDDF8\uDDFE\uDDFF]|\uDDFB\uD83C[\uDDE6\uDDE8\uDDEA\uDDEC\uDDEE\uDDF3\uDDFA]|\uDDFC\uD83C[\uDDEB\uDDF8]|\uDDFD\uD83C\uDDF0|\uDDFE\uD83C[\uDDEA\uDDF9]|\uDDFF\uD83C[\uDDE6\uDDF2\uDDFC]|\uDE01|\uDE02\uFE0F?|[\uDE1A\uDE2F\uDE32-\uDE36]|\uDE37\uFE0F?|[\uDE38-\uDE3A\uDE50\uDE51\uDF00-\uDF20]|[\uDF21\uDF24-\uDF2C]\uFE0F?|[\uDF2D-\uDF35]|\uDF36\uFE0F?|[\uDF37-\uDF7C]|\uDF7D\uFE0F?|[\uDF7E-\uDF84]|\uDF85(?:\uD83C[\uDFFB-\uDFFF])?|[\uDF86-\uDF93]|[\uDF96\uDF97\uDF99-\uDF9B\uDF9E\uDF9F]\uFE0F?|[\uDFA0-\uDFC1]|\uDFC2(?:\uD83C[\uDFFB-\uDFFF])?|[\uDFC3\uDFC4](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDFC5\uDFC6]|\uDFC7(?:\uD83C[\uDFFB-\uDFFF])?|[\uDFC8\uDFC9]|\uDFCA(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDFCB\uDFCC](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?|\uFE0F(?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDFCD\uDFCE]\uFE0F?|[\uDFCF-\uDFD3]|[\uDFD4-\uDFDF]\uFE0F?|[\uDFE0-\uDFF0]|\uDFF3(?:\u200D(?:\u26A7\uFE0F?|\uD83C\uDF08)|\uFE0F(?:\u200D(?:\u26A7\uFE0F?|\uD83C\uDF08))?)?|\uDFF4(?:\u200D\u2620\uFE0F?|\uDB40\uDC67\uDB40\uDC62\uDB40(?:\uDC65\uDB40\uDC6E\uDB40\uDC67|\uDC73\uDB40\uDC63\uDB40\uDC74|\uDC77\uDB40\uDC6C\uDB40\uDC73)\uDB40\uDC7F)?|[\uDFF5\uDFF7]\uFE0F?|[\uDFF8-\uDFFF])|\uD83D(?:[\uDC00-\uDC07]|\uDC08(?:\u200D\u2B1B)?|[\uDC09-\uDC14]|\uDC15(?:\u200D\uD83E\uDDBA)?|[\uDC16-\uDC3A]|\uDC3B(?:\u200D\u2744\uFE0F?)?|[\uDC3C-\uDC3E]|\uDC3F\uFE0F?|\uDC40|\uDC41(?:\u200D\uD83D\uDDE8\uFE0F?|\uFE0F(?:\u200D\uD83D\uDDE8\uFE0F?)?)?|[\uDC42\uDC43](?:\uD83C[\uDFFB-\uDFFF])?|[\uDC44\uDC45]|[\uDC46-\uDC50](?:\uD83C[\uDFFB-\uDFFF])?|[\uDC51-\uDC65]|[\uDC66\uDC67](?:\uD83C[\uDFFB-\uDFFF])?|\uDC68(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:\uDC8B\u200D\uD83D)?\uDC68|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D(?:\uDC66(?:\u200D\uD83D\uDC66)?|\uDC67(?:\u200D\uD83D[\uDC66\uDC67])?|[\uDC68\uDC69]\u200D\uD83D(?:\uDC66(?:\u200D\uD83D\uDC66)?|\uDC67(?:\u200D\uD83D[\uDC66\uDC67])?)|[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92])|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])|\uD83C(?:\uDFFB(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:\uDC8B\u200D\uD83D)?\uDC68\uD83C[\uDFFB-\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D\uDC68\uD83C[\uDFFC-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFC(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:\uDC8B\u200D\uD83D)?\uDC68\uD83C[\uDFFB-\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D\uDC68\uD83C[\uDFFB\uDFFD-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFD(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:\uDC8B\u200D\uD83D)?\uDC68\uD83C[\uDFFB-\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D\uDC68\uD83C[\uDFFB\uDFFC\uDFFE\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFE(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:\uDC8B\u200D\uD83D)?\uDC68\uD83C[\uDFFB-\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D\uDC68\uD83C[\uDFFB-\uDFFD\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFF(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:\uDC8B\u200D\uD83D)?\uDC68\uD83C[\uDFFB-\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D\uDC68\uD83C[\uDFFB-\uDFFE]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?))?|\uDC69(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:\uDC8B\u200D\uD83D)?[\uDC68\uDC69]|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D(?:\uDC66(?:\u200D\uD83D\uDC66)?|\uDC67(?:\u200D\uD83D[\uDC66\uDC67])?|\uDC69\u200D\uD83D(?:\uDC66(?:\u200D\uD83D\uDC66)?|\uDC67(?:\u200D\uD83D[\uDC66\uDC67])?)|[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92])|\uD83E[\uDDAF-\uDDB3\uDDBC\uDDBD])|\uD83C(?:\uDFFB(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF]|\uDC8B\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFC-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFC(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF]|\uDC8B\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB\uDFFD-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFD(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF]|\uDC8B\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB\uDFFC\uDFFE\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFE(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF]|\uDC8B\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFD\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFF(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D\uD83D(?:[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF]|\uDC8B\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFF])|\uD83C[\uDF3E\uDF73\uDF7C\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83D[\uDC68\uDC69]\uD83C[\uDFFB-\uDFFE]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?))?|\uDC6A|[\uDC6B-\uDC6D](?:\uD83C[\uDFFB-\uDFFF])?|\uDC6E(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDC6F(?:\u200D[\u2640\u2642]\uFE0F?)?|[\uDC70\uDC71](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDC72(?:\uD83C[\uDFFB-\uDFFF])?|\uDC73(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDC74-\uDC76](?:\uD83C[\uDFFB-\uDFFF])?|\uDC77(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDC78(?:\uD83C[\uDFFB-\uDFFF])?|[\uDC79-\uDC7B]|\uDC7C(?:\uD83C[\uDFFB-\uDFFF])?|[\uDC7D-\uDC80]|[\uDC81\uDC82](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDC83(?:\uD83C[\uDFFB-\uDFFF])?|\uDC84|\uDC85(?:\uD83C[\uDFFB-\uDFFF])?|[\uDC86\uDC87](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDC88-\uDC8E]|\uDC8F(?:\uD83C[\uDFFB-\uDFFF])?|\uDC90|\uDC91(?:\uD83C[\uDFFB-\uDFFF])?|[\uDC92-\uDCA9]|\uDCAA(?:\uD83C[\uDFFB-\uDFFF])?|[\uDCAB-\uDCFC]|\uDCFD\uFE0F?|[\uDCFF-\uDD3D]|[\uDD49\uDD4A]\uFE0F?|[\uDD4B-\uDD4E\uDD50-\uDD67]|[\uDD6F\uDD70\uDD73]\uFE0F?|\uDD74(?:\uD83C[\uDFFB-\uDFFF]|\uFE0F)?|\uDD75(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?|\uFE0F(?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDD76-\uDD79]\uFE0F?|\uDD7A(?:\uD83C[\uDFFB-\uDFFF])?|[\uDD87\uDD8A-\uDD8D]\uFE0F?|\uDD90(?:\uD83C[\uDFFB-\uDFFF]|\uFE0F)?|[\uDD95\uDD96](?:\uD83C[\uDFFB-\uDFFF])?|\uDDA4|[\uDDA5\uDDA8\uDDB1\uDDB2\uDDBC\uDDC2-\uDDC4\uDDD1-\uDDD3\uDDDC-\uDDDE\uDDE1\uDDE3\uDDE8\uDDEF\uDDF3\uDDFA]\uFE0F?|[\uDDFB-\uDE2D]|\uDE2E(?:\u200D\uD83D\uDCA8)?|[\uDE2F-\uDE34]|\uDE35(?:\u200D\uD83D\uDCAB)?|\uDE36(?:\u200D\uD83C\uDF2B\uFE0F?)?|[\uDE37-\uDE44]|[\uDE45-\uDE47](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDE48-\uDE4A]|\uDE4B(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDE4C(?:\uD83C[\uDFFB-\uDFFF])?|[\uDE4D\uDE4E](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDE4F(?:\uD83C[\uDFFB-\uDFFF])?|[\uDE80-\uDEA2]|\uDEA3(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDEA4-\uDEB3]|[\uDEB4-\uDEB6](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDEB7-\uDEBF]|\uDEC0(?:\uD83C[\uDFFB-\uDFFF])?|[\uDEC1-\uDEC5]|\uDECB\uFE0F?|\uDECC(?:\uD83C[\uDFFB-\uDFFF])?|[\uDECD-\uDECF]\uFE0F?|[\uDED0-\uDED2\uDED5-\uDED7]|[\uDEE0-\uDEE5\uDEE9]\uFE0F?|[\uDEEB\uDEEC]|[\uDEF0\uDEF3]\uFE0F?|[\uDEF4-\uDEFC\uDFE0-\uDFEB])|\uD83E(?:\uDD0C(?:\uD83C[\uDFFB-\uDFFF])?|[\uDD0D\uDD0E]|\uDD0F(?:\uD83C[\uDFFB-\uDFFF])?|[\uDD10-\uDD17]|[\uDD18-\uDD1C](?:\uD83C[\uDFFB-\uDFFF])?|\uDD1D|[\uDD1E\uDD1F](?:\uD83C[\uDFFB-\uDFFF])?|[\uDD20-\uDD25]|\uDD26(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDD27-\uDD2F]|[\uDD30-\uDD34](?:\uD83C[\uDFFB-\uDFFF])?|\uDD35(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDD36(?:\uD83C[\uDFFB-\uDFFF])?|[\uDD37-\uDD39](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDD3A|\uDD3C(?:\u200D[\u2640\u2642]\uFE0F?)?|[\uDD3D\uDD3E](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDD3F-\uDD45\uDD47-\uDD76]|\uDD77(?:\uD83C[\uDFFB-\uDFFF])?|[\uDD78\uDD7A-\uDDB4]|[\uDDB5\uDDB6](?:\uD83C[\uDFFB-\uDFFF])?|\uDDB7|[\uDDB8\uDDB9](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDDBA|\uDDBB(?:\uD83C[\uDFFB-\uDFFF])?|[\uDDBC-\uDDCB]|[\uDDCD-\uDDCF](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDDD0|\uDDD1(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\uD83C[\uDF3E\uDF73\uDF7C\uDF84\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83E\uDDD1|[\uDDAF-\uDDB3\uDDBC\uDDBD]))|\uD83C(?:\uDFFB(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1\uD83C[\uDFFC-\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF84\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83E\uDDD1\uD83C[\uDFFB-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFC(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1\uD83C[\uDFFB\uDFFD-\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF84\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83E\uDDD1\uD83C[\uDFFB-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFD(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1\uD83C[\uDFFB\uDFFC\uDFFE\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF84\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83E\uDDD1\uD83C[\uDFFB-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFE(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1\uD83C[\uDFFB-\uDFFD\uDFFF]|\uD83C[\uDF3E\uDF73\uDF7C\uDF84\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83E\uDDD1\uD83C[\uDFFB-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?|\uDFFF(?:\u200D(?:[\u2695\u2696\u2708]\uFE0F?|\u2764\uFE0F?\u200D(?:\uD83D\uDC8B\u200D)?\uD83E\uDDD1\uD83C[\uDFFB-\uDFFE]|\uD83C[\uDF3E\uDF73\uDF7C\uDF84\uDF93\uDFA4\uDFA8\uDFEB\uDFED]|\uD83D[\uDCBB\uDCBC\uDD27\uDD2C\uDE80\uDE92]|\uD83E(?:\uDD1D\u200D\uD83E\uDDD1\uD83C[\uDFFB-\uDFFF]|[\uDDAF-\uDDB3\uDDBC\uDDBD])))?))?|[\uDDD2\uDDD3](?:\uD83C[\uDFFB-\uDFFF])?|\uDDD4(?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|\uDDD5(?:\uD83C[\uDFFB-\uDFFF])?|[\uDDD6-\uDDDD](?:\u200D[\u2640\u2642]\uFE0F?|\uD83C[\uDFFB-\uDFFF](?:\u200D[\u2640\u2642]\uFE0F?)?)?|[\uDDDE\uDDDF](?:\u200D[\u2640\u2642]\uFE0F?)?|[\uDDE0-\uDDFF\uDE70-\uDE74\uDE78-\uDE7A\uDE80-\uDE86\uDE90-\uDEA8\uDEB0-\uDEB6\uDEC0-\uDEC2\uDED0-\uDED6])"; 

See the regex demo (although the JS option is used, the regex yields the same result in C#.)

The pattern is created dynamically from the list of emojis and contracted using a regex trie, with a couple of post-process steps to shrink the pattern even more.

If you need to check if the whole string is solely composed of emojis, wrap the above pattern with a group, append anchors on both ends, and add + (one or more) / * (zero or more) quantifier to the group.

// If the string should contain at least one emoji: var rx = $@"^(?:{EmojiPattern})+\z"; var rx = $@"^(?:{EmojiPattern})+$"; // Or, to allow empty strings var rx = $@"^(?:{EmojiPattern})*\z"; var rx = $@"^(?:{EmojiPattern})*$"; 

Here, ^ matches the start of string, $ matches the end of string (but there may be a final \n at the end of string) and \z matches the very end of string.

Answer 2

The Unicode Technical Standard #51 defines a regular expression pattern for detecting Emoji based on the Unicode character properties. It needs translation into your language and RegExp library of choice and relies on Unicode support in those patterns.

\p{RI} \p{RI}  | \p{Emoji}    ( \p{EMod}    | \x{FE0F} \x{20E3}?    | [\x{E0020}-\x{E007E}]+ \x{E007F} )?   (\x{200D} \p{Emoji}     ( \p{EMod}      | \x{FE0F} \x{20E3}?      | [\x{E0020}-\x{E007E}]+ \x{E007F} )?   )* 

By relying on these character properties it won't be as necessary to maintain a custom database or table of known characters and combinations. Unicode specification updates should trickle down through the provided framework, language, or platform.

I've done this for JavaScript but alas not for C#, still I'm hoping that this answer helps out.

const emoji = new RegExp(   '(?:' +                                    /*** Proper "Emoji" ***/     '\\p{RI}\\p{RI}' +                       // Regional indicators like 🇦 + 🇸 = 🇦🇸     '|' +     '\\p{Emoji}' +                           // Emoji character     '(?:' +                                  // optionally followed…       '\\p{Emoji_Modifier}' +                //   …with a modifier like skin-tone, hair style, etc…       '|' +       '\\u{FE0F}\\u{20E3}?' +                //   …with "visual representation" marker ☂ vs ☂️       '|' +                                  //         "combining visual keycap" a vs. a⃣       '[\\u{E0020}-\\u{E007E}]+\\u{E007F}' + //   …with Emoji tag sequences for flags     ')?' +     '(?:' +       '\\u{200D}\\p{Emoji}' +                // …with zero or more ZWJ sequences       '(?:' +                                //   …each of which might also have modifier         '\\p{Emoji_Modifier}' +              //      sequences as on the base Emoji above         '|' +         '\\u{FE0F}\\u{20E3}?' +         '|' +         '[\\u{E0020}-\\u{E007E}]+\\u{E007F}' +       ')?' +     ')*' +   ')',   'gu'                                       // Global to find all matches and persist `lastIndex` if necessary ); 

and also as a one-liner with a regex101 link

/(?:\p{RI}\p{RI}|\p{Emoji}(?:\p{Emoji_Modifier}|\u{FE0F}\u{20E3}?|[\u{E0020}-\u{E007E}]+\u{E007F})?(?:\u{200D}\p{Emoji}(?:\p{Emoji_Modifier}|\u{FE0F}\u{20E3}?|[\u{E0020}-\u{E007E}]+\u{E007F})?)*)|[\u{1f900}-\u{1f9ff}\u{2600}-\u{26ff}\u{2700}-\u{27bf}]/gu