Is there a way to exclude certain characters when using flutter list.where-CodePudding

I have a searchDelegate and when user searches, I use the list.where to fetch accordingly, now that I have that down, I have an issue where when user doesn't include some characters like a comma or apostrophe or hypen, it doesn't show those results, EXAMPLE I have a book in my list with title => 'Tis you I want, O Juliet.

when user searches without the apostrophe, or even misses the comma, it won't show that book unless you type it character for character, I want a case where I can make the where() method ignore the user's ignorance if you get me... here's some code snippet.

import 'package:flutter/material.dart';

import 'book.dart';
import 'book_brain.dart';

class MyDelegate extends SearchDelegate<Book> {

  @override
  Widget? buildLeading(BuildContext context) {
    return IconButton(
      icon: const Icon(Icons.arrow_back),
      onPressed: () {
        Navigator.pop(context);
      },
    );
  }

  @override
  List<Widget>? buildActions(BuildContext context) {
    return [
      IconButton(
        icon: const Icon(Icons.clear),
        onPressed: () {
          query.isEmpty ? Navigator.pop(context) : query = '';
        },
      ),
    ];
  }

  @override
  Widget buildResults(BuildContext context) {

    return const Center();
  }

  @override
  Widget buildSuggestions(BuildContext context) {

    List<Book> suggestions = BookBrain().allBooks().where((book) {

      final result = book.bookText.toLowerCase();
      final input = query.toLowerCase();
      final result2 = book.bookTitle.toLowerCase();

      //here I wanna make it ignore when user misses certain characters

      return result.contains(input) || result2.contains(input);

    }).toList();



    return ListView.builder(
        itemCount: suggestions.length,
        itemBuilder: (context, suggestIndex) {
          final suggestion = suggestions[suggestIndex];

          return ListTile(
            title: Text(suggestion.bookTitle),
            trailing: Text('${suggestion.authorName} ${suggestion.bookYear}',
            style: const TextStyle(
              fontStyle: FontStyle.italic,
              fontWeight: FontWeight.w300,
            ),
            ),
            onTap: () {
              close(context, suggestion);
            },
          );
        });
  }
}

CodePudding user response：

You can accomplish this with a regex. result and result2 will have all spaces and special characters removed.

// "It's in 4 hours." -> "itsin4hours"
final result = book.bookText.replaceAll(RegExp('[^A-Za-z0-9]'), '').toLowerCase();
final result2 = book.bookTitle.replaceAll(RegExp('[^A-Za-z0-9]'), '').toLowerCase();

More detailed example here