jQuery选择onChange更新输入字段值

Question

I have multiple sets of select and input s in one form and I need to update each input based on the selected value. Update the price in the input field based on the select dropdown.

The drop-down carries a value and a data attribute. The value is the quantity, and the data-attr is the price.

So when you select <1> from the drop-down, the input will change to <1> * its data-attribute.

I don't want to use ID's or classes or names to get current onChange.

// jQuery onChange this particular {select_drop_down}

<select class="select">
    <option value="1" data-price="2.99">1</option>
    <option value="2" data-price="2.99">2</option>
    <option value="3" data-price="2.99">3</option>
    <option value="4" data-price="2.99">4</option>
</select>

// update this input's value to the selected:index * data-price. // new value: if option value=2 is selected, change input[type=text] to the new value.

<input type="text" value="2.99">

// same goes for the next {select_drop_down}

<select class="select">
    <option value="1" data-price="1.99">1</option>
    <option value="2" data-price="1.99">2</option>
    <option value="3" data-price="1.99">3</option>
    <option value="4" data-price="1.99">4</option>
</select>

<input type="text" value="1.99">

So this is what I have so far:

$(".select").change(function () {
    newPrice = 2.99; // I NEED HERE THE CURRENT data-price value;
    $(".one option:selected").each(function () {
        Price = newPrice*$(".unit").val();
    });
    $(this).nextAll('input').first().focus().val(Price.toFixed(2))
});

this works but only for the first drop-down, not the second.

Answer 1

Within the event change use the following to get the current selected option:

var newPrice = $(this).children(':selected').data('price');

The following code snippet just prints the selected value and set the newPrice to the next input field using $(this).next('input').focus().val(newPrice); .

Now you can do any logic with that value.

 $(".select").change(function () { newPrice = $(this).children(':selected').data('price'); console.log(newPrice); /* $(".one option:selected").each(function () { Price = newPrice*$(".unit").val(); });*/ $(this).next('input').focus().val(newPrice); }); 

 <script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script> <select class="select"> <option value="1" data-price="1.99">1</option> <option value="2" data-price="2.99">2</option> <option value="3" data-price="3.99">3</option> <option value="4" data-price="4.99">4</option> </select> <input type="text" value="1.99">