How to pull in data by using a data-attribute?

Question

I'm trying to pull in data from our API with a data- html trick.. I can call the data directly and it load just fine. But when i try to get the data variable from the data attribute it won't work.

Is there something flawed in my code?

ie

<span id="totalBalanceBTC" data-api-user-getbalance="totalBalance">--</span>

function dataAPI() {
    let balanceUrl = 'https://api.example.io/v1/user/getbalance/username';
    let balanceApiData = getApiData(balanceUrl);

    $('[data-api-user-getbalance]').each(function (){

      let dataUserBalance = $(this).data("api-user-getbalance");
      let data = balanceApiData.dataUserBalance;

        // WORKS
        $(this).html(balanceApiData.totalBalance);

        // DOES NOT WORK
        $(this).html(balanceApiData.dataUserBalance);

    });
  }

Answer 1

1. jQuery's .data() drops the data- prefix and converts the remaining hyphenated string to camelCase , using the dashes as delimiters. It should be:

let dataUserBalance = $(this).data("apiUserGetbalance");

2. To access an object property using a variable, you'll need to use bracket notation . Otherwise you're trying to get the property "dataUserBalance" , which doesn't exist.

let data = balanceApiData[dataUserBalance];

 const balanceApiData = { totalBalance: 500 }; const $elem = $("#totalBalanceBTC"); let dataUserBalance = $elem.data("apiUserGetbalance"); let data = balanceApiData[dataUserBalance]; console.log(data); 

 <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script> <span id="totalBalanceBTC" data-api-user-getbalance="totalBalance"></span>