JavaScript "for" loop selecting JSON Data

Question

OKAYSO, I'm working with some JSON data and formatting it into the DOM, and I'm trying to avoid stuff that looks like this...

var image1 = content.list.story[1].image[0].crop[1].src;
var image2 = content.list.story[1].image[0].crop[1].src;
var image3 = content.list.story[2].image[0].crop[1].src;
var image4 = content.list.story[3].image[0].crop[1].src;

To avoid that, I'm using the following for loop

var count ;
for(count = 0; count < 1; count++){
   console.log("content.list.story["+[count]+"].image[0].crop[1].src");
};

That code prints

content.list.story[0].image[0].crop[1].src

Exactly as it should. However, when I format it to print the actual resource, as such...

var count ;
for(count = 0; count < 1; count++){
   console.log(content.list.story['+[count]+'].image[0].crop[1].src);
};

...it returns undefined.

Any idea what I'm screwing up here?

content.list.story[count].image[0].crop[1].src

Explosion Pills
– Explosion Pills

2017-03-01 19:05:12 +00:00
Commented Mar 1, 2017 at 19:05 — Explosion Pills
– Explosion Pills, Commented Mar 1, 2017 at 19:05

Rafael Dantas · Accepted Answer · 2017-03-01 19:07:33Z

3

The correct code is:

var count ;
for(count = 0; count < 1; count++){
    console.log(content.list.story[count].image[0].crop[1].src);
};

You should use variable with index, in your example, you had put index "[count]" and correct index is "0".

answered Mar 1, 2017 at 19:07

Rafael Dantas

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Comments

holi-java · Accepted Answer · 2017-03-01 19:10:41Z

1

try the code below:

  var count ;
 for(count = 0; count < 1; count++){
   console.log(content.list.story[count].image[0].crop[1].src);
 };

answered Mar 1, 2017 at 19:10

holi-java

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Comments

Tarek El-Mallah · Accepted Answer · 2017-03-01 19:24:29Z

1

I think you are using index from 1 to 4 and you are using 0 in loop. So the array[0] is undefined.

Also even if JSON index begins at 0, the code should be like below, note using "story[count]" not story['+[count]+']

var count ;
for(count = 0; count < 1; count++){
   console.log(content.list.story[count].image[0].crop[1].src);
};

edited Mar 1, 2017 at 19:24

Tarek El-Mallah

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answered Mar 1, 2017 at 19:07

Jake

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1 Comment

Nick Tirrell Over a year ago

Negative. JSON index begins at 0.

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