extension AssetString on String {
  String get ktIcon => "assets/$this";
  // 截断字符串并添加省略号
  String truncate(int maxLength) {
    if (length <= maxLength) return this;
    return '${substring(0, maxLength)}...';
  }

  // 首字母大写
  String capitalize() {
    if (isEmpty) return this;
    return this[0].toUpperCase() + substring(1);
  }

  // 转为 int，失败返回 null
  int? toIntOrNull() => int.tryParse(this);

  // 转为 double，失败返回 null
  double? toDoubleOrNull() => double.tryParse(this);

  // 判断是否为数字
  bool get isNumeric => double.tryParse(this) != null;

  // 去除所有空白
  String get removeAllWhitespace => replaceAll(RegExp(r'\s+'), '');
}

extension NullString on String? {
  bool get isNullString => this == null || (this?.isEmpty ?? false);

  // 安全截断
  String safeTruncate(int maxLength) {
    if (this == null) return '';
    return this!.truncate(maxLength);
  }

  // 安全首字母大写
  String get safeCapitalize => (this?.capitalize() ?? '');
}