如何在 javascript 中访问 function 中的变量值

Question

I have searched on the website for solutions, but I have had no luck. I need to make this data global. My code is present below:

     function val() {
            var plans = @json($plans);
            var id = document.getElementById("plan_id").value;
            plans.forEach(function(element) {
                if (id == element.id) {
                    var  i = element.amount;
                    return i;
                }
            });

        }
        var obj =  val()
        console.log(obj)

After I log that, it wont give any values but if I log inside the foreach, I will get the amount. Pls how can I access data inside foreach

Answer 1

Your function needs to return a value if you want to log it outside like this.

function val() {
  const plans = @json($plans);
  const id = document.getElementById("plan_id").value;
  return plans
    .filter(element => id === element.id)
    .map(element => element.amount);

}

const obj = val()
console.log(obj)

Answer 2

You are not returning anything from the function and return inside forEach is always undefined . Use find

 function val() { var plans = @json($plans); var id = document.getElementById("plan_id").value; return plans.find(element => id === element.id).amount; } var obj = val() console.log(obj)

Answer 3

This would on change get the amountValue from based on what ID you have selected.

var amountValue = null;

function val() {
    var plans = @json($plans);
    var id = document.getElementById("plan_id").value;
    for (i = 0; i < plans.length; i++) {
        if (id === plans[i].id) {
            amountValue = plans[i].amount;
            return amountValue;
        }
    }
}
var obj = val()
console.log(obj)

Answer 4

Thanks everyone, I have fixed my issue, but I follow another process.

I actually get the amount using onclick