How to check if an option is selected?

问题

$(\'#mySelectBox option\').each(function() {
    if ($(this).isChecked())
       alert(\'this option is selected\');
     else
       alert(\'this is not\');
});

Apparently, the isChecked doesn\'t work. SO my question is what is the proper way to do this? Thanks.

回答1:

UPDATE

A more direct jQuery method to the option selected would be:

var selected_option = $('#mySelectBox option:selected');

Answering the question .is(':selected') is what you are looking for:

$('#mySelectBox option').each(function() {
    if($(this).is(':selected')) ...

The non jQuery (arguably best practice) way to do it would be:

$('#mySelectBox option').each(function() {
    if(this.selected) ...

Although, if you are just looking for the selected value try:

$('#mySelectBox').val()

If you are looking for the selected value's text do:

$('#mySelectBox option').filter(':selected').text();

Check out: http://api.jquery.com/selected-selector/

Next time look for duplicate SO questions:

Get current selected option or Set selected option or How to get $(this) selected option in jQuery? or option[selected=true] doesn't work

回答2:

You can get the selected option this way:

$('#mySelectBox option:selected')...

LIVE DEMO

But if you want to iterate all the options, do it with this.selected instead of this.isChecked which doesn't exist:

$('#mySelectBox option').each(function() {
    if (this.selected)
       alert('this option is selected');
     else
       alert('this is not');
});

LIVE DEMO

Update:

You got plenty of answers suggesting you to use this:

$(this).is(':selected') well, it can be done a lot faster and easier with this.selected so why should you use it and not the native DOM element method?!

Read Know Your DOM Properties and Functions in the jQuery tag info

回答3:

If you're not familiar or comfortable with is(), you could just check the value of prop("selected").

As seen here:

$('#mySelectBox option').each(function() {
    if ($(this).prop("selected") == true) {
       // do something
    } else {
       // do something
    }
});

Edit:

As @gdoron pointed out in the comments, the faster and most appropriate way to access the selected property of an option is via the DOM selector. Here is the fiddle update displaying this action.

if (this.selected == true) {

appears to work just as well! Thanks gdoron.

回答4:

Consider this as your select list:

<select onchange="var optionVal = $(this).find(':selected').val(); doSomething(optionVal)">

                                <option value="mostSeen">Most Seen</option>
                                <option value="newst">Newest</option>
                                <option value="mostSell">Most Sell</option>
                                <option value="mostCheap">Most Cheap</option>
                                <option value="mostExpensive">Most Expensive</option>

                            </select>

then you check selected option like this:

function doSomething(param) {

    if ($(param.selected)) {
        alert(param + ' is selected!');
    }

}

回答5:

use

 $("#mySelectBox option:selected");

to test if its a particular option myoption:

 if($("#mySelectBox option:selected").text() == myoption){
          //...
 }

回答6:

You can use this way by jquery :

$(document).ready(function(){
 $('#panel_master_user_job').change(function () {
 var job =  $('#panel_master_user_job').val();
 alert(job);
})
})

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<select name="job" id="panel_master_user_job" class="form-control">
                                    <option value="master">Master</option>
                                    <option value="user">User</option>
                                    <option value="admin">Admin</option>
                                    <option value="custom">Custom</option>
                                </select>

回答7:

In my case I don't know why selected is always true. So the only way I was able to think up is:

var optionSelected = false;
$( '#select_element option' ).each( function( i, el ) {
    var optionHTMLStr = el.outerHTML;

    if ( optionHTMLStr.indexOf( 'selected' ) > 0 ) {
        optionSelected = true;
        return false;
    }
});

回答8:

If you only want to check if an option is selected, then you do not need to iterate through all options. Just do

if($('#mySelectBox').val()){
    // do something
} else {
    // do something else
}

Note: If you have an option with value=0 that you want to be selectable, you need to change the if-condition to $('#mySelectBox').val() != null

回答9:

If you need to check option selected state for specific value:

$('#selectorId option[value=YOUR_VALUE]:selected')

来源：https://stackoverflow.com/questions/10213620/how-to-check-if-an-option-is-selected

标签

jquery

select

option