如何从 Dart 中删除 if-else 链？

Question

我在 Flutter 应用程序中有一个相当大的 if-else 链，它从标题列表中检查一堆条件。 我试图弄清楚如何在没有这一系列 if-else 语句的情况下处理这样的链。 Map 是否合适，或者可能是一个简单的开关盒？

if (listOfMaps[i]["title"] == "BPM LOW" && !activeAlarms.contains("BPM LOW")) {
            activeAlarms.add("BPM LOW");
          } else if (listOfMaps[i]["title"] == "BPM HIGH" && !activeAlarms.contains("BPM HIGH")) {
            activeAlarms.add("BPM HIGH");
          } else if (listOfMaps[i]["title"] == "PIP LOW" &&
              !activeAlarms.contains("PIP LOW")) {
            activeAlarms.add("PIP LOW");
          } else if (listOfMaps[i]["title"] == "PIP HIGH" &&
              !activeAlarms.contains("PIP HIGH")) {
            activeAlarms.add("PIP HIGH");
          }

Answer 1

for (final data in listOfMaps) {
  final title = data["title"];
  if (!activeAlarms.contains(title)) {
    activeAlarms.add(title);
  }
}

Answer 2

List activeAlarms = ["BPM HIGH"];
List listOfMaps = [
  {"title": "BPM LOW"},
  {"title": "BPM HIGH"},
  {"title": "PIP LOW"},
  {"title": "PIP HIGH"},
];
print('listOfMaps:');
print(listOfMaps);

print('activeAlarms before:');
print(activeAlarms);

listOfMaps.forEach((e) {
  activeAlarms.singleWhere((element) => (element == e["title"]), orElse: () {
    activeAlarms.add(e["title"]);
  });
});

print('activeAlarms after:');
print(activeAlarms);

这是一些代码。
和 output：

flutter: listOfMaps:  
flutter: [{title: BPM LOW}, {title: BPM HIGH}, {title: PIP LOW}, {title: PIP HIGH}]  
flutter: activeAlarms before:  
flutter: [BPM HIGH]  
flutter: activeAlarms after:  
flutter: [BPM HIGH, BPM LOW, PIP LOW, PIP HIGH]