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JavaScript

Posted by Łukasz Czuliński
Łukasz Czuliński
8,646 Points

Trying to get value of hidden input but returning 'undefined'.

Hi eall. As said in the title, I'm trying to return the value of an input. 

var itemBar = document.getElementsByClassName('quote-item-bar');


for(var i = 0; i < itemBar.length; i++){
    var position = itemBar[i].getElementsByClassName('position');
    console.log(i, position.value);
}

which returns

0 undefined
1 undefined

Here are the html inputs

<input class="position" name="item_position[]" type="hidden" value="2">
<input class="position" name="item_position[]" type="hidden" value="3">

Despite them having values of 2 and 3 respectively. What super-simple thing am I missing here?

2 Answers

Robert Richey
Robert Richey
Courses Plus Student 16,352 Points

When getting elements by class name, you're getting an array of nodes unless you specify the index you want.

document.getElementsByClassName("position")[i];

An individual input element has a value property but an array of input elements do not.

Edited for clarity

Łukasz Czuliński
Łukasz Czuliński
8,646 Points
Łukasz Czuliński
Łukasz Czuliński
8,646 Points

I get what you mean, but I can't just get all .position elements. I need to get the ones that are only within a particular div (.quote-item-bar). There are more on the page that I want to ignore.

I'm trying to avoid doing this without adding a second class that is unique to these inputs.

Łukasz Czuliński
Łukasz Czuliński
8,646 Points

Nevermind, got it. Because I know there is only one instance of position all I did was:

var position = itemBar[i].getElementsByClassName('position')[0].value;

I suppose I could just do a second for loop within the function if the number is dynamic. Thanks for the help.