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Javascript make object string keys enumerable

Time:05-17

I have a class set up with string keys, like this:

class MyClass {
    constructor() {
        this.id = 0
        this.data = []
    }

    "GET /data"(req, res) {
        res.json(this.data)
    }
}

The goal is to dynamically loop over the functions in an instance like this:

for (let key in new MyClass()) {
    console.log(key)
}

However, everything I have tried has only resulted in the keys id and data.

I can manually get the function and run it just fine:

let item = new MyClass()
item["GET /data"]()

But it does not show up in any dynamic enumeration I have tried.

Manually setting the enumeration also works:

class MyClass {
    constructor() {
        this.id = 0
        this.data = []
        
        // Here!!!
        Object.defineProperty(this, "GET /data", {
            value: this["GET /data"],
            writable: false,
            enumerable: true,
            configurable: true
        })
    }

    "GET /data"(req, res) {
        res.json(this.data)
    }
}

console.log(Object.keys(new MyClass())) // ["id", "data", "GET /data"]

But that defeats the purpose of doing it dynamically. Is there any way to either dynamically get the names of functions with string keys, or make every property enumerable?

CodePudding user response:

Object.getOwnPropertyNames(MyClass.prototype)

gives you

["constructor", "GET /data"]

CodePudding user response:

There are two ways to do this

Object.keys(myObj)

or

for (let key in myObj) {
}
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