Question

I want change name attribute in <input> element, I have in the here several name string[0][], now i want after click on link add change ‍‍0 in they and replace 1 instead all 0. How is it by Jquery?

DEMO: http://jsfiddle.net/2hXk5/

I try as but don’t work for me:

<div class="ch">
    <p>
        <input type="checkbox" name="cDA[0][]">
        <input type="checkbox" name="cDA[0][]">
        <input type="checkbox" name="cDA[0][]">
        <input type="checkbox" name="cDA[0][]">
    </p>
    <p>
        <input type="checkbox" name="cFE[0][]">
        <input type="checkbox" name="cFE[0][]">
        <input type="checkbox" name="cFE[0][]">
        <input type="checkbox" name="cFE[0][]">
    </p>
    <p>
        <input type="checkbox" name="cYG[0][]">
        <input type="checkbox" name="cYG[0][]">
        <input type="checkbox" name="cYG[0][]">
        <input type="checkbox" name="cYG[0][]">
    </p>
    <a href="" class="adding">Add</a>
</div>
​


$('a.adding').live('click change', function (e) {
    e.preventDefault();
    $clone = $(this).closest('.ch').clone().insertAfter('.ch');
    $clone.find('input[type="checkbox"]:contains("0")').prop('1');
})​

Answer 1

If I understand you correctly, you want to use .attr() with a callback function:

$('input[type="checkbox"]').attr('name',function(i,str) {
    return str.replace('0','1');
});

UPDATE: Here’s a complete version which will do everything you seem to actually want. It uses str.match(/\d+/) to extract the FIRST number-string in the name attribute, converts it to an integer, then replaces it with the next integer using str.replace. Note the insertAfter part was updated so it only inserts after the LAST div.ch:

$(document).on('click change', 'a.adding', function(e) {
    e.preventDefault();
    $div = $(this).closest('.ch');
    $clone = $div.clone().insertAfter($div);
    $clone.find('input[type="checkbox"]').attr('name', function(i, str) {
        var int = parseInt(str.match(/\d+/)[0],10);
        return str.replace(int, (int+1));
    });
});​

http://jsfiddle.net/mblase75/3SGNw/