打字稿方法装饰器 [英] Typescript Method Decorator

问题描述

我有此代码

function changeFunc() {
    return function(target: any, title: string, descriptor: PropertyDescriptor) {

        descriptor.value = function () {
            console.log(this.name);
        };

        return descriptor;

    }
}


class Man {
    name: string = "asdsds";

    constructor(name: string) {
        this.name = name;
    }

    @changeFunc()
    getName() {
        console.log("Hello");
    }

}


var man = new Man('Manos Serifios');
man.getName();  

换句话说，我尝试(与装饰器)进行更改方法

In other words i try (with the decorator) to change the method

getName() {  
    console.log("Hello");  
}  

与此

function () {
    console.log(this.name);
}

但是this.name被评估为未定义.

but this.name evaluated as undefined.

如果我在控制台上登录"this"，则似乎是正确的(实例人).

If i console log the "this" it seems that is the right(instance man).

推荐答案

您在decorator方法中没有特定的 object实例的上下文.参数如下(来自 https://www.typescriptlang.org/docs/handbook/decorators.html ):

You don't have the context of a specific object instance inside the decorator method. The parameters are the following (from https://www.typescriptlang.org/docs/handbook/decorators.html):

是静态成员的类的构造函数，还是实例成员的类的原型.

成员的名字.

成员的属性描述符.

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