[英]React add property to immutable object
I'm trying to add a new property to objects within an array. 我正在尝试向数组中的对象添加新属性。 My idea was to do something like this:
我的想法是做这样的事情:
class Foo extends Component {
constructor(props) {
super(props);
this.state = this.getInitialState();
console.log(this.state); //Property "label" is missing in "members" array
}
/**
* Get initial state
* @returns {{title, description}}
*/
getInitialState = () => {
let members = this.props.members.slice();
members.map((member) => {
return {
...member,
label: (member.firstName + " " + member.lastName)
}
});
console.log(members); //"label" is not a property of objects
return {title: "", description: "", responsible: [], typeOf: null,
members: members};
};
render () {
return (<div/>)
}
}
I want members
to stay/remain immutable, yet adding another property to every object within this array. 我希望
members
保持/保持不变,但要向此数组内的每个对象添加另一个属性。 What am I doing wrong here? 我在这里做错了什么? Thanks!
谢谢!
You are not storing returned value of map to members variable 您没有存储映射到成员变量的返回值
getInitialState = () => {
let members = this.props.members.map((member) => {
return {
...member,
label: (member.firstName + " " + member.lastName)
}
});
console.log(members); //"label" is not a property of objects
return {title: "", description: "", responsible: [], typeOf: null,
members: members};
};
数组原型.map()不会更改原始数组,但会返回一个新数组。
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