How to generate array key using array index in for on the associative array in javascript

Question

Is it possible to generate array keys using the array index in the "for" to create associative arrays?

I want the values in the index array in the "for" to be used as keys in the associative array

The sample code that you want to get the value for making an associative array is in the middle of the *** sign:

                 if(data.status == 422){
                    let msg = data.responseJSON.errors;
                    let msgObject = Object.keys(msg);
                    
                    for (let i = 0; i < msgObject.length; i++) {
                        if (msg[msgObject[i]]) {
                            let msgObjectIndex = msgObject[i];

                            let columnIndex = {
                                       ||
                                       \/
                                ***msgObject[i]*** : column[msgObject[i]]
                                       /\
                                       ||
                            };
                            console.log(columnIndex);
                            
                        }
                    }
                }else {
                    alert('Please Reload to read Ajax');
                    console.log("ERROR : ", e);
                    }
                },

then variable column is:

let column = {
            'nama_paket' : $('.edit_error_nama_paket'), 
            'tipe_berat' : $('.edit_error_tipe_berat'), 
            'harga'      : $('.edit_error_harga'), 
            'id_service' : $('.edit_error_id_service'),
        };

I tried the code above to get the following error: Uncaught SyntaxError: Unexpected token '[' thanks

Answer 1

You can generate computed property names with [] syntax

Simple example:

 let obj = {}; ['a','b','c'].forEach((e,i) => { let computed = {[e]:i}; Object.assign(obj, computed) }) console.log(obj)

Answer 2

Here couple of ways you can do, see my comments.

1. one way is as suggested by @charlietlf.
2. After object creation, add the key/value

    let msg = data.responseJSON.errors;
    let msgObject = Object.keys(msg);
    
    for (let i = 0; i < msgObject.length; i++) {
      if (msg[msgObject[i]]) {
        let msgObjectIndex = msgObject[i];
    
        const newKey1 = `MyNewKey${2 + 3}`; // sample
        let columnIndex = {
          // One way is
          [newKey1]: column[msgObject[i]],
        };
    
        // Alternatively, we can add the generated key and value to obj
        const newKey2 = msgObject[i];
        //  or something like newKey2 = `MyKey${msgObject[i]}`
        columnIndex[newKey2] = column[msgObject[i]];
    
        console.log(columnIndex);
      }
    }