How to convert UTF-8 strings to ascii in Dart/Flutter [duplicate] - flutter

I'm trying to convert some strings that are in Czech, Spanish, French etc. I'd like to take out the accent marks in the letters while keeping the letter. (E.g. convert é to e, č to c, Ž to Z, ñ to n)
What is the best way to achieve this?
Btw, there is a good similar question/answer for JavaScript

Not throughougly tested but seems to work
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 = RegExp('[^\u0000-\u007E]', multiLine: true);
String removeDiacritics(String str) {
if(diacriticsMap.isEmpty) {
for (int i = 0; i < defaultDiacriticsRemovalap.length; i++){
var letters = defaultDiacriticsRemovalap[i]['letters'];
for (int j = 0; j < letters.length; j++) {
diacriticsMap[letters[j]] = defaultDiacriticsRemovalap[i]['base'];
}
}
}
return str.replaceAllMapped(diacriticsRegExp, (a){
return diacriticsMap[a.group(0)] ?? a.group(0);
});
}
Try it at DartPad
See also https://pub.dartlang.org/packages/diacritic

Another simple solution that worked for me:
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;
}

Here's my adaptation of Leonardo's solution. It extends the string class for ease of use and uses SplitMapJoin instead of a for loop:
extension DiacriticsAwareString on String {
static const diacritics =
'ÀÁÂÃÄÅàáâãäåÒÓÔÕÕÖØòóôõöøÈÉÊËĚèéêëěðČÇçčÐĎďÌÍÎÏìíîïĽľÙÚÛÜŮùúûüůŇÑñňŘřŠšŤťŸÝÿýŽž';
static const nonDiacritics =
'AAAAAAaaaaaaOOOOOOOooooooEEEEEeeeeeeCCccDDdIIIIiiiiLlUUUUUuuuuuNNnnRrSsTtYYyyZz';
String get withoutDiacriticalMarks => this.splitMapJoin('',
onNonMatch: (char) => char.isNotEmpty && diacritics.contains(char)
? nonDiacritics[diacritics.indexOf(char)]
: char);
}

use just the library to make diacritic strings:
https://pub.dev/packages/diacritic
Example from the docs:
import 'package:diacritic/diacritic.dart';
main() {
// prints 'arvizturo tukorfurogep'
print(removeDiacritics('árvíztűrő tükörfúrógép'));
}

This is a slightly more flexible solution. it uses replaceAllMapped and has the advantages to replace also continuations symbols such ææ æ with ae
extension StringExtensions on String {
String replaceAllDiacritics() {
return replaceAllMapped(
RegExp('[À-ž]'),
(m) => diacriticsMapping[m.group(0)] ?? '',
);
}
// put here your mapping, this cover chars corresponding to regex [À-ž]
static const diacriticsMapping = {
//[À-ÿ]
'À': 'A',
'Á': 'A',
'Â': 'A',
'Ã': 'A',
'Ä': 'A',
'Å': 'A',
'Æ': 'AE',
'Ç': 'C',
'È': 'E',
'É': 'E',
'Ê': 'E',
'Ë': 'E',
'Ì': 'I',
'Í': 'I',
'Î': 'I',
'Ï': 'I',
'Ð': 'D',
'Ñ': 'N',
'Ò': 'O',
'Ó': 'O',
'Ô': 'O',
'Õ': 'O',
'Ö': 'O',
'×': 'x', //math multiplication
'Ø': 'O',
'Ù': 'U',
'Ú': 'U',
'Û': 'U',
'Ü': 'U',
'Ý': 'Y',
'Þ': 'TH',
'ß': 'SS',
'à': 'a',
'á': 'a',
'â': 'a',
'ã': 'a',
'ä': 'a',
'å': 'a',
'æ': 'ae',
'ç': 'c',
'è': 'e',
'é': 'e',
'ê': 'e',
'ë': 'e',
'ì': 'i',
'í': 'i',
'î': 'i',
'ï': 'i',
'ð': 'd',
'ñ': 'n',
'ò': 'o',
'ó': 'o',
'ô': 'o',
'õ': 'o',
'ö': 'o',
'÷': ' ', //math division
'ø': 'o',
'ù': 'u',
'ú': 'u',
'û': 'u',
'ü': 'u',
'ý': 'y',
'þ': 'th',
'ÿ': 'y',
//[Ā-ž] EuropeanLatin
'Ā': 'A',
'ā': 'a',
'Ă': 'A',
'ă': 'a',
'Ą': 'A',
'ą': 'a',
'Ć': 'C',
'ć': 'c',
'Ĉ': 'C',
'ĉ': 'c',
'Ċ': 'C',
'ċ': 'c',
'Č': 'C',
'č': 'c',
'Ď': 'D',
'ď': 'd',
'Đ': 'D',
'đ': 'd',
'Ē': 'E',
'ē': 'e',
'Ĕ': 'E',
'ĕ': 'e',
'Ė': 'E',
'ė': 'e',
'Ę': 'E',
'ę': 'e',
'Ě': 'E',
'ě': 'e',
'Ĝ': 'G',
'ĝ': 'g',
'Ğ': 'G',
'ğ': 'g',
'Ġ': 'G',
'ġ': 'g',
'Ģ': 'G',
'ģ': 'g',
'Ĥ': 'H',
'ĥ': 'h',
'Ħ': 'H',
'ħ': 'h',
'Ĩ': 'I',
'ĩ': 'i',
'Ī': 'I',
'ī': 'i',
'Ĭ': 'I',
'ĭ': 'i',
'Į': 'I',
'į': 'i',
'İ': 'I',
'ı': 'i',
'IJ': 'IJ',
'ij': 'ij',
'Ĵ': 'J',
'ĵ': 'j',
'Ķ': 'K',
'ķ': 'k',
'ĸ': 'k',
'Ĺ': 'L',
'ĺ': 'l',
'Ļ': 'L',
'ļ': 'l',
'Ľ': 'L',
'ľ': 'l',
'Ŀ': 'L',
'ŀ': 'l',
'Ł': 'L',
'ł': 'l',
'Ń': 'N',
'ń': 'n',
'Ņ': 'N',
'ņ': 'n',
'Ň': 'N',
'ň': 'n',
'ʼn': 'n',
'Ŋ': 'N',
'ŋ': 'n',
'Ō': 'O',
'ō': 'o',
'Ŏ': 'O',
'ŏ': 'o',
'Ő': 'O',
'ő': 'o',
'Œ': 'OE',
'œ': 'oe',
'Ŕ': 'R',
'ŕ': 'r',
'Ŗ': 'R',
'ŗ': 'r',
'Ř': 'R',
'ř': 'r',
'Ś': 'S',
'ś': 's',
'Ŝ': 'S',
'ŝ': 's',
'Ş': 'S',
'ş': 's',
'Š': 'S',
'š': 's',
'Ţ': 'T',
'ţ': 't',
'Ť': 'T',
'ť': 't',
'Ŧ': 'T',
'ŧ': 't',
'Ũ': 'U',
'ũ': 'u',
'Ū': 'U',
'ū': 'u',
'Ŭ': 'U',
'ŭ': 'u',
'Ů': 'U',
'ů': 'u',
'Ű': 'U',
'ű': 'u',
'Ų': 'U',
'ų': 'u',
'Ŵ': 'W',
'ŵ': 'w',
'Ŷ': 'Y',
'ŷ': 'y',
'Ÿ': 'Y',
'Ź': 'Z',
'ź': 'z',
'Ż': 'Z',
'ż': 'z',
'Ž': 'Z',
'ž': 'z',
};

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'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w',
'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '.', ',', ';', ':', '-',
'_', ' ', '!', '#', '#', '\$', '%', '^', '&', '*', '(', ')', '+', '=', '\"', '№', '~', '?',
'\\', '/', '|', '[', ']', '{', '}', '`', '\'', '<', '>'];
late dynamic keyWord = ' ';
late dynamic text = ' ';
late dynamic res;
late dynamic a4;
late dynamic m;
late dynamic n;
late dynamic f;
var d = 0;
var k = 0;
var z = 0;
var operation = 0;
var m1 = 0;
var c = 0;
encode(keyWord, text){
late dynamic res;
var l = (text.length) as int;
for( var i = l ; i >= 1; i-- ){
if(symbols.contains(text[d])) {
var f = symbols.indexOf(text[d]);
a4 = '';
if(f == 0){
a4 = '0';
while(f > 0){
a4 = (f % 4).toString() + a4.toString();
f = f ~/ 4;
}
a4 = '$a4';
}
}
else{
a4 += '1123';
}
while(a4.length != 4) {
a4 = '0' + a4;
}
for( var j = 4 ; j >= 1; j-- ){
res += (keyWord[(a4[z]) as int]);
res.whenComplete((){
setState(() {});
});
z += 1;
}
z = 0;
d += 1;
}
return(res);
}
The encode function does not work due to LateInitializationError: Local 'res' has not been initialized.
The rest of the code works correctly, the res
variable was not called anywhere except for this function. Maybe someone faced the same problem or knows how to solve it? I would be grateful for your help.
Exception is pretty self-explanatory. You access res in res += (keyWord[(a4[z]) as int]);, when it's not yet initialized. You should remove late and do dynamic res = '' for example.
P.S. 'res += value' is basically 'res = res + value'. That's why you get the error
P.S.S Why not to use some typing? Your code's res.whenComplete will fail, because it's not a Future. Seems, that you don't use any code completion at all.

Text Corrector Function

I'm trying to make a stringCorrector function for avoiding non-English words, but don't know how to implement this to string in Dart;
as an example;
İstanbul ====> Istanbul, New York===> NewYork, İşÇöÜ===>IsCoU
String stringCorrector(String string) {
Map<String, String> correcterMap = {
'ö': 'o',
'ü': 'u',
'Ö': 'O',
'Ü': 'U',
'İ': 'I',
'ı': 'i',
'ğ': 'g',
'Ğ': 'G',
' ': ''
};
}
May be I can help you if I understand the use of this. For the first two examples, it is relatively easy, but for the third one you will need to have a whole map of values to replace.
You would get something like this :
String stringCorrector(String string) {
Map<String, String> correcterMap = {
'ö': 'o',
'ü': 'u',
'Ö': 'O',
'Ü': 'U',
'İ': 'I',
'ı': 'i',
'ğ': 'g',
'Ğ': 'G',
' ': '',
};
correcterMap.forEach((key, value) {
string = string.replaceAll(RegExp(key), value);
});
return string;}
It's just a matter of mapping the string and reducing that result.
String stringCorrector(String string) {
Map<String, String> correcterMap = {
'ö': 'o',
'ü': 'u',
'Ö': 'O',
'Ü': 'U',
'İ': 'I',
'ı': 'i',
'ğ': 'g',
'Ğ': 'G',
' ': ''
};
return string.runes.map(
(int charCode) {
String char = String.fromCharCode(charCode);
return correcterMap[char] ?? char;
}
).reduce((a, b) => a + b);
}

I am getting Range error like Invalid value: Not in range 16..17, inclusive: 19Error: RangeError (end):

I am using Dart pad for to show the list items using sublist but i am getting range error here is my code please help me.
void main() {
var list = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q','f','e','y'];
for(int i=0;i<list.length;i++) {
if(i.isEven && i<list.length-1)
print(list.sublist(i,i+2));
else
print(list.sublist(i,i+3));
}
}
You tried accessing some items outside the list with i + 3. Using i<list.length-2 will allow the compiler to check if the item is in the list before trying to print the value.
void main() {
var list = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q'];
for(int i=0;i<list.length;i++) {
if(i.isEven && i<list.length-2)
print(list.sublist(i,i+2));
else if(i<list.length-2)
print(list.sublist(i, i+3));
}
}

Replacing string with empty vector

I'm trying to modify this code so that if the input of this function contains the letter 'Z', it will return return an empty vector. I am able to do this for the letter 'Q' or 'Z' if it is at the beginning of string, but unfortunately it won't work if either of these two letters are at the end.
function d = change(a)
new_claim = regexprep(a, 'A', '2');
new_claim1 = regexprep(new_claim, 'B', '2');
new_claim2 = regexprep(new_claim1, 'C', '2');
new_claim3 = regexprep(new_claim2, 'D', '3');
new_claim4 = regexprep(new_claim3, 'E', '3');
new_claim5 = regexprep(new_claim4, 'F', '3');
new_claim6 = regexprep(new_claim5, 'G', '4');
new_claim7 = regexprep(new_claim6, 'H', '4');
new_claim8 = regexprep(new_claim7, 'I', '4');
new_claim9 = regexprep(new_claim8, 'J', '5');
new_claim10 = regexprep(new_claim9, 'K', '5');
new_claim11 = regexprep(new_claim10, 'L', '5');
new_claim12 = regexprep(new_claim11, 'M', '6');
new_claim13 = regexprep(new_claim12, 'N', '6');
new_claim14 = regexprep(new_claim13, 'O', '6');
new_claim15 = regexprep(new_claim14, 'P', '7');
new_claim16 = regexprep(new_claim15, 'R', '7');
new_claim17 = regexprep(new_claim16, 'S', '7');
new_claim18 = regexprep(new_claim17, 'T', '8');
new_claim19 = regexprep(new_claim18, 'U', '8');
new_claim20 = regexprep(new_claim19, 'V', '8');
new_claim21 = regexprep(new_claim20, 'W', '9');
new_claim22 = regexprep(new_claim21, 'X', '9');
new_claim23 = regexprep(new_claim22, 'Y', '9');
new_claim24 = regexprep(new_claim23, '-', ' ');
new_claim25 = regexprep(new_claim24, '(', '');
new_claim26 = regexprep(new_claim25, ')','');
d = new_claim26;
if strfind(d,'Q') == true
d = [];
elseif strfind(d,'Z') == true
d = [];
else
return;
end
If it's your desire to check to see if a string contains the letter Z or z, maybe put this at the beginning of your code:
if ~isempty(regexp(a, '[Zz]'))
d = [];
return;
end
If you also wanted to check for Q or q, you can do:
if ~isempty(regexp(a, '[ZzQq]'))
d = [];
return;
end
The above uses a regular expression to see if there are any characters in your string that contain either Z or z (or Q or q, depending on what you want). regexp returns the indices of where these characters were found. If there were Z or z (or Q or q characters, depending on what you want) characters found, then the indices would be non-empty, hence the ~isempty check. If there were no Z or z (or Q or q) characters that were found, this would be empty and so this statement is skipped. What's important is that if we have found Z, z (or Q, q) characters, we immediately make d empty and return so that the rest of the logic is not run.
You can then carry on with the rest of your code.
You can check if a character is in a string with: any(d == 'Q') || any(d == 'Z')

Send image to web service

I want send an image from my App to web service, to do it, im send the data like an NSData, but it do nothing:
NSData *imagen= UIImagePNGRepresentation(windowImage);
The Web Service wait the data like: base64Binary
To send this type of data, i know that i need convert the NSData to NSString using the famous method "base64Encoding"
NSData *imagen=UIImagePNGRepresentation(windowImage);
NSString *encoded= [imagen base64Encoding];
And i Send the data like SOAP:
NSString *soapMsg= [NSString stringWithFormat:............<imagenBase64>%#<imagenBase64>,encoded];
Where is the error? I need to do other conversion?
See the following answers. Do like this.
NSData *imagen=UIImagePNGRepresentation(windowImage);
NSString *base64String = [self base64StringFromData:imagen length:[imagen length]];
Now, send this base64string to your web service.
static char base64EncodingTable[64] = {
'A', 'B', 'C', 'D', 'E', 'F', 'G', 'H', 'I', 'J', 'K', 'L', 'M', 'N', 'O', 'P',
'Q', 'R', 'S', 'T', 'U', 'V', 'W', 'X', 'Y', 'Z', 'a', 'b', 'c', 'd', 'e', 'f',
'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v',
'w', 'x', 'y', 'z', '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', '+', '/'
};
+ (NSString *) base64StringFromData: (NSData *)data length: (int)length {
unsigned long ixtext, lentext;
long ctremaining;
unsigned char input[3], output[4];
short i, charsonline = 0, ctcopy;
const unsigned char *raw;
NSMutableString *result;
lentext = [data length];
if (lentext < 1)
return #"";
result = [NSMutableString stringWithCapacity: lentext];
raw = [data bytes];
ixtext = 0;
while (true) {
ctremaining = lentext - ixtext;
if (ctremaining <= 0)
break;
for (i = 0; i < 3; i++) {
unsigned long ix = ixtext + i;
if (ix < lentext)
input[i] = raw[ix];
else
input[i] = 0;
}
output[0] = (input[0] & 0xFC) >> 2;
output[1] = ((input[0] & 0x03) << 4) | ((input[1] & 0xF0) >> 4);
output[2] = ((input[1] & 0x0F) << 2) | ((input[2] & 0xC0) >> 6);
output[3] = input[2] & 0x3F;
ctcopy = 4;
switch (ctremaining) {
case 1:
ctcopy = 2;
break;
case 2:
ctcopy = 3;
break;
}
for (i = 0; i < ctcopy; i++)
[result appendString: [NSString stringWithFormat: #"%c", base64EncodingTable[output[i]]]];
for (i = ctcopy; i < 4; i++)
[result appendString: #"="];
ixtext += 3;
charsonline += 4;
if ((length > 0) && (charsonline >= length))
charsonline = 0;
}
return result;
}
I tried the code which Raj posted as an answer, and worked perfectly for my iPhone app.
But then I realised that you can do the same thing using one line of code:
NSString* base64string = [imageData base64EncodedStringWithOptions:NSDataBase64Encoding76CharacterLineLength];
And to convert your base64 string back into a binary:
NSData* imageData = [[NSData alloc] initWithBase64EncodedString:base64string options:0];
Blimey.
For once, with Objective-C, that was easier than expected...!