如何从字符串中删除变音符号（重音符号）？

Question

我正在尝试转换一些捷克语，西班牙语，法语等字符串。我想在保留字母的同时取出字母中的重音符号。 （例如，将é转换为e，č至c，Ž至Z，ñ至n）

实现这一目标的最佳方法是什么？

不过，有一个很好的similar question/answer for JavaScript

Answer 1

未经过严格测试但似乎有效

void main() {
      var paragraph = "L'avantage d'utiliser le lorem ipsum est bien évidemment de pouvoir créer des maquettes ou de remplir un site internet de contenus qui présentent un rendu s'approchant un maximum du rendu final. \n Par défaut lorem ipsum ne contient pas d'accent ni de caractères spéciaux contrairement à la langue française qui en contient beaucoup. C'est sur ce critère que nous proposons une solution avec cet outil qui générant du faux-texte lorem ipsum mais avec en plus, des caractères spéciaux tel que les accents ou certains symboles utiles pour la langue française. \n L'utilisation du lorem standard est facile d’utilisation mais lorsque le futur client utilisera votre logiciel il se peut que certains caractères spéciaux ou qu'un accent ne soient pas codés correctement. \n Cette page a pour but donc de pouvoir perdre le moins de temps possible et donc de tester directement si tous les encodages de base de donnée ou des sites sont les bons de plus il permet de récuperer un code css avec le texte formaté !";
   print(removeDiacritics(paragraph));
}

final defaultDiacriticsRemovalap = [
    {'base':'A', 'letters':'\u0041\u24B6\uFF21\u00C0\u00C1\u00C2\u1EA6\u1EA4\u1EAA\u1EA8\u00C3\u0100\u0102\u1EB0\u1EAE\u1EB4\u1EB2\u0226\u01E0\u00C4\u01DE\u1EA2\u00C5\u01FA\u01CD\u0200\u0202\u1EA0\u1EAC\u1EB6\u1E00\u0104\u023A\u2C6F'},
    {'base':'AA','letters':'\uA732'},
    {'base':'AE','letters':'\u00C6\u01FC\u01E2'},
    {'base':'AO','letters':'\uA734'},
    {'base':'AU','letters':'\uA736'},
    {'base':'AV','letters':'\uA738\uA73A'},
    {'base':'AY','letters':'\uA73C'},
    {'base':'B', 'letters':'\u0042\u24B7\uFF22\u1E02\u1E04\u1E06\u0243\u0182\u0181'},
    {'base':'C', 'letters':'\u0043\u24B8\uFF23\u0106\u0108\u010A\u010C\u00C7\u1E08\u0187\u023B\uA73E'},
    {'base':'D', 'letters':'\u0044\u24B9\uFF24\u1E0A\u010E\u1E0C\u1E10\u1E12\u1E0E\u0110\u018B\u018A\u0189\uA779'},
    {'base':'DZ','letters':'\u01F1\u01C4'},
    {'base':'Dz','letters':'\u01F2\u01C5'},
    {'base':'E', 'letters':'\u0045\u24BA\uFF25\u00C8\u00C9\u00CA\u1EC0\u1EBE\u1EC4\u1EC2\u1EBC\u0112\u1E14\u1E16\u0114\u0116\u00CB\u1EBA\u011A\u0204\u0206\u1EB8\u1EC6\u0228\u1E1C\u0118\u1E18\u1E1A\u0190\u018E'},
    {'base':'F', 'letters':'\u0046\u24BB\uFF26\u1E1E\u0191\uA77B'},
    {'base':'G', 'letters':'\u0047\u24BC\uFF27\u01F4\u011C\u1E20\u011E\u0120\u01E6\u0122\u01E4\u0193\uA7A0\uA77D\uA77E'},
    {'base':'H', 'letters':'\u0048\u24BD\uFF28\u0124\u1E22\u1E26\u021E\u1E24\u1E28\u1E2A\u0126\u2C67\u2C75\uA78D'},
    {'base':'I', 'letters':'\u0049\u24BE\uFF29\u00CC\u00CD\u00CE\u0128\u012A\u012C\u0130\u00CF\u1E2E\u1EC8\u01CF\u0208\u020A\u1ECA\u012E\u1E2C\u0197'},
    {'base':'J', 'letters':'\u004A\u24BF\uFF2A\u0134\u0248'},
    {'base':'K', 'letters':'\u004B\u24C0\uFF2B\u1E30\u01E8\u1E32\u0136\u1E34\u0198\u2C69\uA740\uA742\uA744\uA7A2'},
    {'base':'L', 'letters':'\u004C\u24C1\uFF2C\u013F\u0139\u013D\u1E36\u1E38\u013B\u1E3C\u1E3A\u0141\u023D\u2C62\u2C60\uA748\uA746\uA780'},
    {'base':'LJ','letters':'\u01C7'},
    {'base':'Lj','letters':'\u01C8'},
    {'base':'M', 'letters':'\u004D\u24C2\uFF2D\u1E3E\u1E40\u1E42\u2C6E\u019C'},
    {'base':'N', 'letters':'\u004E\u24C3\uFF2E\u01F8\u0143\u00D1\u1E44\u0147\u1E46\u0145\u1E4A\u1E48\u0220\u019D\uA790\uA7A4'},
    {'base':'NJ','letters':'\u01CA'},
    {'base':'Nj','letters':'\u01CB'},
    {'base':'O', 'letters':'\u004F\u24C4\uFF2F\u00D2\u00D3\u00D4\u1ED2\u1ED0\u1ED6\u1ED4\u00D5\u1E4C\u022C\u1E4E\u014C\u1E50\u1E52\u014E\u022E\u0230\u00D6\u022A\u1ECE\u0150\u01D1\u020C\u020E\u01A0\u1EDC\u1EDA\u1EE0\u1EDE\u1EE2\u1ECC\u1ED8\u01EA\u01EC\u00D8\u01FE\u0186\u019F\uA74A\uA74C'},
    {'base':'OI','letters':'\u01A2'},
    {'base':'OO','letters':'\uA74E'},
    {'base':'OU','letters':'\u0222'},
    {'base':'OE','letters':'\u008C\u0152'},
    {'base':'oe','letters':'\u009C\u0153'},
    {'base':'P', 'letters':'\u0050\u24C5\uFF30\u1E54\u1E56\u01A4\u2C63\uA750\uA752\uA754'},
    {'base':'Q', 'letters':'\u0051\u24C6\uFF31\uA756\uA758\u024A'},
    {'base':'R', 'letters':'\u0052\u24C7\uFF32\u0154\u1E58\u0158\u0210\u0212\u1E5A\u1E5C\u0156\u1E5E\u024C\u2C64\uA75A\uA7A6\uA782'},
    {'base':'S', 'letters':'\u0053\u24C8\uFF33\u1E9E\u015A\u1E64\u015C\u1E60\u0160\u1E66\u1E62\u1E68\u0218\u015E\u2C7E\uA7A8\uA784'},
    {'base':'T', 'letters':'\u0054\u24C9\uFF34\u1E6A\u0164\u1E6C\u021A\u0162\u1E70\u1E6E\u0166\u01AC\u01AE\u023E\uA786'},
    {'base':'TZ','letters':'\uA728'},
    {'base':'U', 'letters':'\u0055\u24CA\uFF35\u00D9\u00DA\u00DB\u0168\u1E78\u016A\u1E7A\u016C\u00DC\u01DB\u01D7\u01D5\u01D9\u1EE6\u016E\u0170\u01D3\u0214\u0216\u01AF\u1EEA\u1EE8\u1EEE\u1EEC\u1EF0\u1EE4\u1E72\u0172\u1E76\u1E74\u0244'},
    {'base':'V', 'letters':'\u0056\u24CB\uFF36\u1E7C\u1E7E\u01B2\uA75E\u0245'},
    {'base':'VY','letters':'\uA760'},
    {'base':'W', 'letters':'\u0057\u24CC\uFF37\u1E80\u1E82\u0174\u1E86\u1E84\u1E88\u2C72'},
    {'base':'X', 'letters':'\u0058\u24CD\uFF38\u1E8A\u1E8C'},
    {'base':'Y', 'letters':'\u0059\u24CE\uFF39\u1EF2\u00DD\u0176\u1EF8\u0232\u1E8E\u0178\u1EF6\u1EF4\u01B3\u024E\u1EFE'},
    {'base':'Z', 'letters':'\u005A\u24CF\uFF3A\u0179\u1E90\u017B\u017D\u1E92\u1E94\u01B5\u0224\u2C7F\u2C6B\uA762'},
    {'base':'a', 'letters':'\u0061\u24D0\uFF41\u1E9A\u00E0\u00E1\u00E2\u1EA7\u1EA5\u1EAB\u1EA9\u00E3\u0101\u0103\u1EB1\u1EAF\u1EB5\u1EB3\u0227\u01E1\u00E4\u01DF\u1EA3\u00E5\u01FB\u01CE\u0201\u0203\u1EA1\u1EAD\u1EB7\u1E01\u0105\u2C65\u0250'},
    {'base':'aa','letters':'\uA733'},
    {'base':'ae','letters':'\u00E6\u01FD\u01E3'},
    {'base':'ao','letters':'\uA735'},
    {'base':'au','letters':'\uA737'},
    {'base':'av','letters':'\uA739\uA73B'},
    {'base':'ay','letters':'\uA73D'},
    {'base':'b', 'letters':'\u0062\u24D1\uFF42\u1E03\u1E05\u1E07\u0180\u0183\u0253'},
    {'base':'c', 'letters':'\u0063\u24D2\uFF43\u0107\u0109\u010B\u010D\u00E7\u1E09\u0188\u023C\uA73F\u2184'},
    {'base':'d', 'letters':'\u0064\u24D3\uFF44\u1E0B\u010F\u1E0D\u1E11\u1E13\u1E0F\u0111\u018C\u0256\u0257\uA77A'},
    {'base':'dz','letters':'\u01F3\u01C6'},
    {'base':'e', 'letters':'\u0065\u24D4\uFF45\u00E8\u00E9\u00EA\u1EC1\u1EBF\u1EC5\u1EC3\u1EBD\u0113\u1E15\u1E17\u0115\u0117\u00EB\u1EBB\u011B\u0205\u0207\u1EB9\u1EC7\u0229\u1E1D\u0119\u1E19\u1E1B\u0247\u025B\u01DD'},
    {'base':'f', 'letters':'\u0066\u24D5\uFF46\u1E1F\u0192\uA77C'},
    {'base':'g', 'letters':'\u0067\u24D6\uFF47\u01F5\u011D\u1E21\u011F\u0121\u01E7\u0123\u01E5\u0260\uA7A1\u1D79\uA77F'},
    {'base':'h', 'letters':'\u0068\u24D7\uFF48\u0125\u1E23\u1E27\u021F\u1E25\u1E29\u1E2B\u1E96\u0127\u2C68\u2C76\u0265'},
    {'base':'hv','letters':'\u0195'},
    {'base':'i', 'letters':'\u0069\u24D8\uFF49\u00EC\u00ED\u00EE\u0129\u012B\u012D\u00EF\u1E2F\u1EC9\u01D0\u0209\u020B\u1ECB\u012F\u1E2D\u0268\u0131'},
    {'base':'j', 'letters':'\u006A\u24D9\uFF4A\u0135\u01F0\u0249'},
    {'base':'k', 'letters':'\u006B\u24DA\uFF4B\u1E31\u01E9\u1E33\u0137\u1E35\u0199\u2C6A\uA741\uA743\uA745\uA7A3'},
    {'base':'l', 'letters':'\u006C\u24DB\uFF4C\u0140\u013A\u013E\u1E37\u1E39\u013C\u1E3D\u1E3B\u017F\u0142\u019A\u026B\u2C61\uA749\uA781\uA747'},
    {'base':'lj','letters':'\u01C9'},
    {'base':'m', 'letters':'\u006D\u24DC\uFF4D\u1E3F\u1E41\u1E43\u0271\u026F'},
    {'base':'n', 'letters':'\u006E\u24DD\uFF4E\u01F9\u0144\u00F1\u1E45\u0148\u1E47\u0146\u1E4B\u1E49\u019E\u0272\u0149\uA791\uA7A5'},
    {'base':'nj','letters':'\u01CC'},
    {'base':'o', 'letters':'\u006F\u24DE\uFF4F\u00F2\u00F3\u00F4\u1ED3\u1ED1\u1ED7\u1ED5\u00F5\u1E4D\u022D\u1E4F\u014D\u1E51\u1E53\u014F\u022F\u0231\u00F6\u022B\u1ECF\u0151\u01D2\u020D\u020F\u01A1\u1EDD\u1EDB\u1EE1\u1EDF\u1EE3\u1ECD\u1ED9\u01EB\u01ED\u00F8\u01FF\u0254\uA74B\uA74D\u0275'},
    {'base':'oi','letters':'\u01A3'},
    {'base':'ou','letters':'\u0223'},
    {'base':'oo','letters':'\uA74F'},
    {'base':'p','letters':'\u0070\u24DF\uFF50\u1E55\u1E57\u01A5\u1D7D\uA751\uA753\uA755'},
    {'base':'q','letters':'\u0071\u24E0\uFF51\u024B\uA757\uA759'},
    {'base':'r','letters':'\u0072\u24E1\uFF52\u0155\u1E59\u0159\u0211\u0213\u1E5B\u1E5D\u0157\u1E5F\u024D\u027D\uA75B\uA7A7\uA783'},
    {'base':'s','letters':'\u0073\u24E2\uFF53\u00DF\u015B\u1E65\u015D\u1E61\u0161\u1E67\u1E63\u1E69\u0219\u015F\u023F\uA7A9\uA785\u1E9B'},
    {'base':'t','letters':'\u0074\u24E3\uFF54\u1E6B\u1E97\u0165\u1E6D\u021B\u0163\u1E71\u1E6F\u0167\u01AD\u0288\u2C66\uA787'},
    {'base':'tz','letters':'\uA729'},
    {'base':'u','letters': '\u0075\u24E4\uFF55\u00F9\u00FA\u00FB\u0169\u1E79\u016B\u1E7B\u016D\u00FC\u01DC\u01D8\u01D6\u01DA\u1EE7\u016F\u0171\u01D4\u0215\u0217\u01B0\u1EEB\u1EE9\u1EEF\u1EED\u1EF1\u1EE5\u1E73\u0173\u1E77\u1E75\u0289'},
    {'base':'v','letters':'\u0076\u24E5\uFF56\u1E7D\u1E7F\u028B\uA75F\u028C'},
    {'base':'vy','letters':'\uA761'},
    {'base':'w','letters':'\u0077\u24E6\uFF57\u1E81\u1E83\u0175\u1E87\u1E85\u1E98\u1E89\u2C73'},
    {'base':'x','letters':'\u0078\u24E7\uFF58\u1E8B\u1E8D'},
    {'base':'y','letters':'\u0079\u24E8\uFF59\u1EF3\u00FD\u0177\u1EF9\u0233\u1E8F\u00FF\u1EF7\u1E99\u1EF5\u01B4\u024F\u1EFF'},
    {'base':'z','letters':'\u007A\u24E9\uFF5A\u017A\u1E91\u017C\u017E\u1E93\u1E95\u01B6\u0225\u0240\u2C6C\uA763'}
];

final diacriticsMap = {};

final diacriticsRegExp = new RegExp('[^\u0000-\u007E]', multiLine: true);

String removeDiacritics(String str) {
  if(diacriticsMap.isEmpty) {
    for (var i=0; i < defaultDiacriticsRemovalap.length; i++){
      var letters = defaultDiacriticsRemovalap[i]['letters'];
      for (var j=0; j < letters.length ; j++){
          diacriticsMap[letters[j]] = defaultDiacriticsRemovalap[i]['base'];
      }
    }
  }
    // "what?" version ... http://jsperf.com/diacritics/12
  return str.replaceAllMapped(diacriticsRegExp, (a){
    return diacriticsMap[a.group(0)] != null ? diacriticsMap[a.group(0)] : a.group(0);
  });
}

在DartPad

尝试

另见https://pub.dartlang.org/packages/diacritic

Answer 2

另一个对我有用的简单解决方案：

String removeDiacritics(String str) {

  var withDia = 'ÀÁÂÃÄÅàáâãäåÒÓÔÕÕÖØòóôõöøÈÉÊËèéêëðÇçÐÌÍÎÏìíîïÙÚÛÜùúûüÑñŠšŸÿýŽž';
  var withoutDia = 'AAAAAAaaaaaaOOOOOOOooooooEEEEeeeeeCcDIIIIiiiiUUUUuuuuNnSsYyyZz'; 

  for (int i = 0; i < withDia.length; i++) {      
    str = str.replaceAll(withDia[i], withoutDia[i]);
  }

return str;

}