JSFiddle - React, Tailwind, and code Playground

HTML

<div>
        <div class="container">
            <p class="primary_key">1</p>
            <p class="content">content1</p>
        </div>
        <div class="container">
            <p class="primary_key">2</p>
            <p class="content">content2</p>
        </div>
    </div>

CSS

.primary_key{
            display: none;
        }

JavaScript

var allContainer = document.getElementsByClassName('container');
    for(var i=0; i<allContainer.length; i++){
        var container =  allContainer[i];
        allContainer[i].innerHTML = document.getElementsByClassName('container');
            clickContainer(container);
        }
    }


function clickContainer(ele){
    var selectedId = ele.getElementsByClassName('primary_key')[0].innerHTML;
    alert(selectedId);
}