Dart String Extensions

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extension StringX on String {
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  // Capitalize first letter
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  String get capitalize => isEmpty ? this : '${this[0].toUpperCase()}${substring(1)}';
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  // Title case every word
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  String get titleCase => split(' ').map((w) => w.capitalize).join(' ');
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  // Truncate with ellipsis
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  String truncate(int maxLength, {String ellipsis = '...'}) {
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    if (length <= maxLength) return this;
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    return '${substring(0, maxLength - ellipsis.length)}$ellipsis';
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  }
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  // Validation
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  bool get isValidEmail {
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    return RegExp(r'^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$').hasMatch(this);
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  }
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  bool get isValidUrl {
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    return RegExp(r'^https?:\/\/(www\.)?[-a-zA-Z0-9@:%._+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b').hasMatch(this);
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  }
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  bool get isValidPhone => RegExp(r'^[+]?[0-9]{8,15}$').hasMatch(replaceAll(' ', ''));
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  // Parsing
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  int?    get toIntOrNull    => int.tryParse(this);
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  double? get toDoubleOrNull => double.tryParse(this);
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  // Utils
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  String get removeHtml    => replaceAll(RegExp('<[^>]*>'), '');
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  String get toSlug        => toLowerCase().trim().replaceAll(RegExp(r'[^a-z0-9]+'), '-');
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  bool   get isBlank       => trim().isEmpty;
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  bool   get isNotBlank    => !isBlank;
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  String get nullIfBlank   => isBlank ? '' : this; // or return null with nullable
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}
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extension NullableStringX on String? {
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  bool get isNullOrEmpty  => this == null || this!.isEmpty;
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  bool get isNullOrBlank  => this == null || this!.isBlank;
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  String get orEmpty      => this ?? '';
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}
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// Usage
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'hello world'.titleCase;          // 'Hello World'
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'bilal@bidev.site'.isValidEmail;  // true
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'Flutter is awesome!'.truncate(14); // 'Flutter is ...'
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'  '.isBlank;                      // true