Jquery add and remove table rows

Question

I have a html table that dynamically adds and removes rows with jQuery. The number of rows is limited by jQuery counter which allows a user to add up to 4 rows. My problem is that when a user creates the 4th row they have reached the limit but when they delete a row the limit still remains in place and they can't add any more rows.

http://jsfiddle.net/nallad1985/sqrrt/

HTML

<table id="myTable" class="order-list">
<thead>
    <tr>
        <td>Name</td>
        <td>Price</td>
    </tr>
</thead>
<tbody>
    <tr>
        <td>
            <input type="text" name="name" />
        </td>
        <td>
            <input type="text" name="price1" />
        </td>
        <td><a class="deleteRow"></a>
        </td>
    </tr>
</tbody>
<tfoot>
    <tr>
        <td colspan="5" style="text-align: left;">
            <input type="button" id="addrow" value="Add Row" />
        </td>
    </tr>
    <tr>
        <td colspan="">Grand Total: $<span id="grandtotal"></span>

        </td>
    </tr>
</tfoot>

JQUERY

$(document).ready(function () {
var counter = 0;
$("#addrow").on("click", function () {
    var counter = $('#myTable tr').length - 2;
    var newRow = $("<tr>");
    var cols = "";

    cols += '<td><input type="text" name="name' + counter + '"/></td>';
    cols += '<td><input type="text" name="price' + counter + '"/></td>';

    cols += '<td><input type="button" id="ibtnDel"  value="Delete"></td>';
    newRow.append(cols);
    if (counter == 4) $('#addrow').attr('disabled', true).prop('value', "You've reached the limit");
    $("table.order-list").append(newRow);
    counter++;
});

$("table.order-list").on("change", 'input[name^="price"]', function (event) {
    calculateRow($(this).closest("tr"));
    calculateGrandTotal();
});

$("table.order-list").on("click", "#ibtnDel", function (event) {
    $(this).closest("tr").remove();
    calculateGrandTotal();
});

});

function calculateRow(row) {
var price = +row.find('input[name^="price"]').val();

}

function calculateGrandTotal() {
var grandTotal = 0;
$("table.order-list").find('input[name^="price"]').each(function () {
    grandTotal += +$(this).val();
});
$("#grandtotal").text(grandTotal.toFixed(2));
}

Answer 1

Bunch of fixes,

1. Removed extra handler for delete button
2. change button ID to class as you should not duplicate ID. Read why you should not duplicate ID .
3. Added logic to enable the Add row button. See Fixed fiddle .
4. Removed var declaration inside Add Row handler to update the global var

http://jsfiddle.net/sqrrt/2/

$("table.order-list").on("click", ".ibtnDel", function (event) {
    $(this).closest("tr").remove();
    calculateGrandTotal();

    counter -= 1
    $('#addrow').attr('disabled', false).prop('value', "Add Row");
});

Answer 2

You just need to re-enable your button and decrement the counter when you delete a row:

$("table.order-list").on("click", "#ibtnDel", function (event) {
    $(this).closest("tr").remove();
    calculateGrandTotal();
    counter--;
    $('#addrow').prop('disabled', false).prop('value', "Add row");
});

Answer 3

On click on delete btn you should decrease your counter number and enabled the buton and property value

$("table.order-list").on("click", "#ibtnDel", function (event) {
    $(this).closest("tr").remove();
    calculateGrandTotal();
    counter = counter-1;
    $("#addrow").attr("disabled", false).prop("value", "Add Row")

});

Answer 4

I updated your javascript please look at the code on fiddle:

http://jsfiddle.net/sqrrt/3/

$("table.order-list").on("click", "#ibtnDel", function (event) {
    $(this).closest("tr").remove();
    calculateGrandTotal();
    counter --;
    if (counter < 5) $('#addrow').attr("disabled", false).prop('value', "Add Row");
});

The problem was, that you did not properly count down the counter and your method for the delete-button did not get called.