如何使用jQuery或JavaScript更改选定的值

Question

I have a that I want to change the selected one late using a function which is trig onClick later in the app.

<select id="myselect">
<option value=aa>aa</option>
<option value=bb>bb</option>
<option value=cc>cc</option>
</select>

then by click on a button a function will run and send a query to mysql using php. Let say that php responds me back "bb" then how can I change this select to be selected on bb??

document.getElementById('myselect').value="bb"; 

does not work.

Answer 1

Add an identifier to your select element such as an ID, then you can just set the value with .val() .

<select id="mySelect">
    <option value="aa">aa</option>
    <option value="bb">bb</option>
    <option value="cc">cc</option>
</select>

In jQuery once you receive your AJAX response, set the value

$('#mySelect').val(phpResponseValue);

Where phpResponseValue is the value returned from the AJAX response such as aa .

Answer 2

HTML:

<select id="mySelect">
<option value=aa>aa</option>
<option value=bb>bb</option>
<option value=cc>cc</option>
</select>

jQuery :

$("#mySelect").val('bb');

Answer 3

$('.button').click(function(){

    $.ajax({
        type: "POST",
        url: "test.php",
        success: function(data){

               $('.select_class').val(data);

        }
    }); 

});

Answer 4

You can use jQuery val() method, but you can also use the basic javascript function and properties of the select (which have a better performance)

select.selectedIndex

is the current selected index, so you can select what you want by setting this propertie

select.options

is the array of options in your select