Dynamic naming of variable in JavaScript in for loop

Question

I have a requirement where in I have to populate these variables using for loop in JavaScript digitalData.option1.name1 digitalData.option2.name2 so on..... I tried below code

var i=1;
for(some conditions){
digitalData.this["option"+i].this["option"+i] = value;
i++;
}

But it is showing syntax error and I also tried this Window["digitalData.option+i+.name+i"] But digitaData is not getting populated

Remove `this` and `.` in this line `digitalData.this["option"+i].this["option"+i]` — Sagar Jajoriya, Mar 18 '18 at 18:47
@SagarJajoriya Unfortunately it's not that *easy* as that will result in `cannot set property name0 of undefined`. — connexo, Mar 18 '18 at 18:57

connexo · Accepted Answer · 2018-03-18T19:25:38.440

1

Use

var digitalData = digitalData || {}

for (let i = 0; i < 10; i++) {
  digitalData["option"+i] = digitalData["option"+i] || {}
  digitalData["option"+i]["name"+i] = i
}

console.log(digitalData)

You need to do the setting in two steps, otherwise you get a cannot set property name0 of undefined error.

edited Mar 18 '18 at 19:25

answered Mar 18 '18 at 18:47

connexo

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I was wondering what if we had something like digitalData.pageInfo.marketing.option1.name1???..will this also follow same steps??? – Abdullah Sholapur Mar 18 '18 at 19:23
Be careful if some of those properties already exist - you probably don't want to overwrite these then using `= {}`. I'll update my answer to make it safer. – connexo Mar 18 '18 at 19:25
Please ask a new question. – connexo Mar 18 '18 at 22:09

Dynamic naming of variable in JavaScript in for loop

1 Answers1