[Jufry]

Sorry for this question, I am a beginner.

Don’t I know about this?

    function test() {
        const idObj = [{"constructor":"constructor", "home":"home"}]
        const idArr = ["constructor", "home"]
        console.log("results: ", idObj["constructor"], idArr["constructor"])
    }

I cant use the “constructor” string as object or array value. Output from the code above is:

results: function Array() { [native code] } function Array() { [native code] }

Can someone teach me about this?

 

Thanks 🙂

 

[Filippo]

Hi Jufry,

thank you for reaching out to us and don’t worry, beginner questions are fine.

 

Here you’re missing the concepts of JavaScript Arrays and Objects. A JavaScript array is a list of elements that you access by position, while JavaScript Objects are basically key-value pairs. Here’s a few samples:

                const jsArray = ["a", "b", "c"]
                console.log(jsArray[0], jsArray[1], jsArray[2]) // prints: a b c

                const jsObject = { "a": 1, "b": 2, "c": 3 }
                console.log(jsObject["a"], jsObject["b"], jsObject["c"]) // prints: 1 2 3

                // You can also have arrays of objects
                const arrayOfObjects = [{"a": 1}, {"b": 2}, {"c": 3}]

                // And objects can contain arrays
                const objectWithArray = { "a": [1, 2, 3] }

In your example you’re basically treating both as object and trying to access the property with the key “constructor”, which is actually a javascript function.

 

Hope this is clear enough to get you started.