如何使用jquery将多个数组输入相乘

Question

My form

<div class="form-inline form-group">
    <div class="input-group form-group">
    <input class="form-control" type="text" name="budget-value1[]" size="3" placeholder="10">
    <label>hrs x</label>
    <input class="form-control" type="text" name="budget-value2[]" size="3" placeholder="10">
    <select class="form-control" name="budget-type2[]" id="type">
    <label>usd x</label>
    <input class="form-control" type="text" name="budget-value3[]" size="3" placeholder="10">
    <label>person x</label>
    <input class="form-control" type="text" name="budget-value4[]" size="3" placeholder="10">
    <label>days =</label>
    <input class="form-control" type="text" name="budget-sum[]" size="4" value="" readonly="readonly" style="cursor:not-allowed;">
    <label>usd</label>
    </div>
</div>

I want to multiply 4 value and display on budget-sum How can I get it?

Answer 1

You might do as follows;

var sum = [...document.querySelector("div.form-inline.form-group")
                      .querySelectorAll("input[placeholder=10]")].reduce((p,c) => p+c)

and then insert the sum value to

document.querySelector("div.form-inline.form-group")
        .querySelector("input[size=4]")