Angular 2实例化类具有空值 [英] Angular 2 instantiate class with empty values

问题描述

如何将成员实例化为具有空值的类?

How do you instantiate the members as class with empty values?

Plunkr

Plunkr

我用

public members = new MemberClass();

但是控制台显示Member:{}，所以我无法设置默认的空值

but the console shows Members: {} so I'm unable to set the default empty values

所以基本上我正在尝试复制一个空结构，如:

so basically I'm trying to replicate an empty structure like:

this.members = [ 
    { 
      "Name" : "", "Id" : "", "Team" : "",
      "Cases" : {
        "history" : []
      }
    }
];

推荐答案

使用接口;)这是一种可以创建带有属性设置为Member的空对象的Array的方法.我不知道用例，至少我没有为空对象/模型数组设置属性，但是我们开始:)

Use interfaces ;) And this is a way you can create an Array with an empty object of type Member with properties set. I don't know the use case, at least I do not set the properties for empty objects/arrays of models, but here we go :)

首先，您的界面是:

export interface Member {
    Id: string;
    Name: string;
    Cases: Case[];
}
export interface History {
    Id: string;
    CaseNumber: string;
}
export interface Case {
    History: History[];
}

然后您创建3个函数来设置属性:

Then you create 3 functions to set the properties:

export function createMember(Id?:string,Name?:string, Cases?:Case[]): Member {
  return {
    Id,
    Name,
    Cases[createCase()]       
  }
}

export function createCase(History?:History[]): Case {
  return {
    History[createHistory()]
  }
}

export function createHistory(Id?: string,CaseNumber?:string): History {
  return {
    Id,
    CaseNumber
  }
}

现在您可以在组件中调用函数createMember，然后调用其他两个函数:

And now in your component you can call the function createMember, that then calls the two other functions:

members = [createMember()];

PS，根据您的模型，以下不是Member -array的模型，它们的名称和构建不匹配，但是我是根据您提供的模型创建的.

PS, according to your models, the following is not the model of Member-array, they name and build doesn't match, but I have created the above, based on the models you have provided.

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