使用jquery在循环内获取特定的文本框值

I have a problem to get particular textbox value inside a loop using jquery. please see the below code. I will get 1 to 10 values all the textbox next to print the button. when I submit that particular textbox value, it will always coming that first value as "1".

I know in jquet code I have to put "$this" key word to get that particular value, but I am new to jquery and I tried so many methods to do that, I failed. please help.

<?PHP for($i=0, $i<10; $i++) ?>
<input type="text" name="ad_id" value="<?PHP echo $i; ?>" class="ad_id" />
<button type="button" class="ad_increase">Submit</button>
<?PHP } ?>


<script>
$('.ad_increase').click(function() {
    var get_ad_id = $('.ad_id').each();


    $.post('includes/show_ad_id.php', {
        ad_id: get_ad_id
    }, function(res) {

        if (res != 1) {
            $('.display_in_model').html(res);
        } else {
            $('.display_in_model').html('');
        }

    });

});
</script>

Try

$(".ad_id").each(function() {
    alert($(this).val());
});

Use prev() to get the value of previous input. Also, change each() to val() to get the value of the input.

var get_ad_id = $(this).prev('.ad_id').val();

Code

$('.ad_increase').on('click', function() {
    var get_ad_id = $(this).prev('.ad_id').val();
    //              ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

    $.post('includes/show_ad_id.php', {
        ad_id: get_ad_id
    }, function(res) {
        if (res != 1) {
            $('.display_in_model').html(res);
        } else {
            $('.display_in_model').html('');
        }
    });
});