es6 class 函数中的 this[functionName] 导致 "Element implicitly has an 'any' type because expression of type string can't be used to index"

Question

我正在尝试使用 es6 classes 创建类似服务的命令，如下所示：

class Person {
    run(){
        console.log("running");
    }
    walk(){
        console.log("walking");
    }
    talk(){
        console.log("talking");
    }
    execute(name: string){
       this[name]()
    }
}

const me = new Person();

me.execute('run');
me.execute('walk');
me.execute('talk');

这是完全有效的，但打字稿在 this[name] 部分咆哮：

TS7053: Element implicitly has an 'any' type because expression of type 'string' can't be used to index type 'Person'.

在这种情况下如何将“名称”参数定义为 class Person 成员类型？

Answer 1

定义名称类型如下

execute(name: "talk" | "walk" | "run") {
    this[name]()
}

Answer 2

鉴于键可以是除 execute 本身之外的任何 class 键，您可以按如下方式定义参数类型：

execute(name: Exclude<keyof Person, 'execute'>){
   this[name]();
}

您可以在此 TypeScript playground 上看到它的实际效果。

es6 class 函数中的 this[functionName] 导致 "Element implicitly has an 'any' type because expression of type string can't be used to index"

this[functionName] in an es6 class function cause "Element implicitly has an 'any' type because expression of type string can't be used to index"

typescript

es6-class