Dart List 用法小结

Posted 2021-09-13 bigshot

一、map结合..操作符更改数组中的某一个字段，其他字段不变

void main() {

  List<PersonModel> list =[
    PersonModel(name:\'kobe1\',age:20,sex:1),
    PersonModel(name:\'kobe2\',age:30,sex:2),
    PersonModel(name:\'kobe3\',age:40,sex:1),
  ];

// map 使用..操作符后会改变原来的List  
list.map((e)=>e..name = \'new name\').toList();
  
  for(var item in list){
    print(item.toJson());
  }
// 打印输出
// {name: new name, age: 20, sex: 1}
// {name: new name, age: 30, sex: 2}
// {name: new name, age: 40, sex: 1}
}


class PersonModel {
  String name;
  int age;
  int sex;

  PersonModel({this.name, this.age, this.sex});

  PersonModel.fromJson(Map<String, dynamic> json) {
    name = json[\'name\'];
    age = json[\'age\'];
    sex = json[\'sex\'];
  }

  Map<String, dynamic> toJson() {
    final Map<String, dynamic> data = new Map<String, dynamic>();
    data[\'name\'] = this.name;
    data[\'age\'] = this.age;
    data[\'sex\'] = this.sex;
    return data;
  }
}