Question 108458 in Javascript Question posted in
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Javascript – Can't use argument of js function on JSON

I have an object like this:

const myObj = [
{
 "name": "harry",
 "id_1": "j-347",
 "id_2": "j-303"
}, 
{
 "name": "liouk",
 "id_1": "k-398",
 "id_2": "k-945"
}
]

If I want to access hary’s id_1 (or id_2) I have to type

myObj[0].id_1 (or id_2)

I have this function:

function getId(counter, id) {
 console.log(counter);
 console.log(id)
 console.log(myObj[counter].id;
}

but when I call getId(0, "id_1") I get:

0
id_1
undefined

In addition, if I delete the line "console.log(id)" from the function, my code editor tells me that ‘id’ is declared but its value is never read, despite the fact that I use it on the last line of the function.
It seems like the argument "id_1" not be recognized after the . (console.log(myObj[counter].id;)

What do I do wrong?

Tags:

2

Answers


  1. 0

    It’s not possible to access object properties dynamically using dot notation . However, with Bracket notation [], you can use a variable to dynamically access object properties.

    const myObj = [{
    "name": "harry",
    "id_1": "j-347",
    "id_2": "j-303"
  },
  {
    "name": "liouk",
    "id_1": "k-398",
    "id_2": "k-945"
  }
]

function getId(counter, id) {
  console.log(counter);
  console.log(id)
  console.log(myObj[counter][id]);
  }
getId(0, "id_1")
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  2. 0

    the function you have written needs a little tweak, as id property doesnt exist inside the array u have provided instead u are passing it as string, which is pointing to the required property

    function getId(counter, id) {
  console.log(counter);
  console.log(id)
  console.log(myObj[counter][id]);
}
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