Flutter String Utils - All Time useful

string_utils.dart

extension StringExtensions on String? {
  String? get capitalize {
    if (this == null) return null;
    final firstLetter = this![0].toUpperCase();
    final rest = this!.substring(1);
    return '$firstLetter$rest';
  }

  String? get toLowerSnackCase {
    if (this == null) return null;
    // Replace all non-alphanumeric characters with underscores, then lowercase
    return this!.replaceAll(RegExp(r'[^a-zA-Z0-9]'), '_').toLowerCase();
  }
}