How can I use data in a string to update a javascript object?

Question

I have the following data array:

var ans = 
[
 {"text":"x","response":false},
 {"text":"y","response":false},
 {"text":"z","response":true}
];

var correct = "010"; // I need to add this to the array ans

Can anyone suggest how I could use use the data in the correct variable to add to the array so as to make:

var ans = 
[
 {"text":"x","response":false,"correct":false},
 {"text":"y","response":false,"correct":true},
 {"text":"z","response":true,"correct":false}
];

What are you trying to do? – Kyle Emmanuel Jul 24 '14 at 05:07 — Kyle Emmanuel, Jul 24 '14 at 05:07

score 2 · Accepted Answer · answered Jul 24 '14 at 05:06

2

for(var i=0; i< ans.length; i++) {
    ans[i].correct = correct.charAt(i) == "1";
}

answered Jul 24 '14 at 05:06

Anton L

412
4
12

I see you are setting the value to "1" will this be the same as setting to true? – Samantha J T Star Jul 24 '14 at 05:33
I'm not setting it to 1. I'm setting it to a result of (correct.charAt(i) == "1") comparison which is a boolean value: true or false – Anton L Jul 24 '14 at 05:36

score 2 · Answer 2 · answered Jul 24 '14 at 05:08

2

for (var i = 0; i < correct.length; i++) {
    ans[i]["correct"] = correct[i] === "1";
}

answered Jul 24 '14 at 05:08

jw2013

64
1
1
3

I see you are setting the value to "1" will this be the same as setting to true? – Samantha J T Star Jul 24 '14 at 05:33
We are not setting the value to "1", we are setting the value to the result of comparison (correct[i] === "1"), which can be either true or false. – jw2013 Jul 24 '14 at 07:28

score 1 · Answer 3 · edited May 23 '17 at 10:33

1

You an also do it like this(using a for-in loop).

Reference: For-each over an array in JavaScript?

for(key in ans){
    ans[key].correct = correct.charAt(key) == "1";
}

edited May 23 '17 at 10:33

Community

1
1

answered Jul 24 '14 at 05:20

Kyle Emmanuel

2,193
1
15
22

I see you are setting the value to "1" will this be the same as setting to true? – Samantha J T Star Jul 24 '14 at 05:35

score 0 · Answer 4 · answered Jul 24 '14 at 05:20

var ans = 
    [
     {"text":"x","response":false},
     {"text":"y","response":false},
     {"text":"z","response":true}
    ];

var correct = "010";

var sep = correct.split("");

var arr = [];

for (var i = 0; i < sep.length; i++) {
     if (sep[i] == 0) {
       arr.push("false");
      } else {
       arr.push("true");
     }
   }

  var len = ans.length;

 for (var i = 0; i < len; i++) {

        ans[i].correct = arr[i];
    }

How can I use data in a string to update a javascript object?

4 Answers4