速記字段初始上課時已經計算財產

Question

比方說，我有一個非常簡單的類與計算性能：

class Person { 
    firstName: string; 
    lastName: string; 

    get fuillName(): string { 
    return this.firstName + ' ' + this.lastName; 
    } 
} 

現在我想創建Person類型的對象：

let p: Person = { 
    firstName: 'John', 
    lastName: 'Smith' 
}; 

這給我一個錯誤：

Type '{ firstName: string; lastName: string; }' is not assignable to type 'Person'. Property 'fuillName' is missing in type '{ firstName: string; lastName: string; }'.

咦？ fullName是隻讀屬性。所以我跟着this question並實現了部分初始化器：

constructor(init?: Partial<Person>) { 
    Object.assign(this, init); 
} 

同樣的錯誤。我知道我可以做到這一點：

let p = new Person(); 
p.firstName = 'John'; 
p.lastName = 'Smith'; 
console.debug(p.fullName); 

但是有沒有簡短的手段來初始化類使用JSON語法？

Answer 1

如果你定義Person類如下：

class Person { 
    firstName?: string; 
    lastName?: string; 

    constructor(values: Object = {}) { 
     Object.assign(this, values); 
    } 

    get fullName(): string { 
     return this.firstName + ' ' + this.lastName; 
    } 
    } 

，你可以初始化一個新的用戶，如下所示：

let p = new Person({firstName : 'John', lastName: 'Smith'}); //one line, two assignations 
    console.log(p.fullName); 

再進一步：

class Person { 
    ....// as above 
    set fullName(fullName: string){ 
     let splitName = fullName.split(" "); 
     this.firstName = splitName[0] || ''; 
     this.lastName = splitName[1] || ''; 
    } 
    } 

    let p = new Person() 
    p.fullName = "Paul Doe"; 

Plunker Demo

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