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dart中地图值的访问列表?_Dart - Fatal编程技术网

dart中地图值的访问列表?

dart中地图值的访问列表?,dart,Dart,我有这个地图列表,如何从这个地图访问每个索引的“答案”值 var questions = [ { "question": "Whats your favourite color?", "answers": ["Red", "Green", "Yellow"] }, { "question": "Whats your favourite animal?", "answers": ["Tiger", "Elephant", "U

我有这个地图列表,如何从这个地图访问每个索引的“答案”值

var questions = [
    {
      "question": "Whats your favourite color?",
      "answers": ["Red", "Green", "Yellow"]
    },
    {
      "question": "Whats your favourite animal?",
      "answers": ["Tiger", "Elephant", "Unicorn"]
    },
    {
      "question": "Whats your favourite game?",
      "answers": ["Tiger", "Elephant", "Unicorn"]
    }
  ];

这只是一个对象列表。您只需通过以下方式访问:

questions.forEach((element) {
  print(element['answers']);
});
以及打印答案:

questions.forEach((element) {
  var answers = element['answers'];
  answers.forEach((answer) {
    print(answer);
  });
});

questions.forEach((元素)=>print(元素['answers'])
(\u问题[\u索引++][“答案”]作为列表)[i++]
只是一天的提示。您只需编写
answers.forEach(print)
即可,它将自动为每个元素调用
print
方法。在第二个代码中获取此错误-没有为类“Object”定义方法“forEach”。-““对象”来自“dart:core”,Try
var answers=element['answers']作为列表。问题是编译器无法猜测
元素['answers']
返回的类型。