jQuery“属性开头”选择器未定义

Question

I have a modal dialog (Bootstrap) that has a list-group with custom list-group-items inside of it (populated by loop using append after adding data from my server).

Inside each list-group-item, I have a Checkbox that will be used to "select" the result. As I populate the items, I hook up the JQuery click event to the respective Checkbox:

            // Add to search results
            $('#search-results').append(
            '<a id="centroid-list-item-' + featureAttrs['ObjectID'] + '" href="\\#"' + 'class="list-group-item" style="outline: 0">' +
            '<table style="background: transparent">' +
                '<tr>' +
                    '<td>' +
                        '<input id="centroid-checkbox-' + featureAttrs['ObjectID'] + '" type="checkbox" value="">&nbsp;&nbsp;' +
                    '</td>' +
                    '<td>' +
                        '<h4 class="list-group-item-heading">' +
                            featureAttrs['UNIQUEID'] +
                        '</h4>' +
                        '<p id="centroid-item-text-' + featureAttrs['ObjectID'] + '"' + 'class="list-group-item-text">' +
                            featureAttrs['NAME'] +
                        '</p>' +
                    '</td>' +
                '</tr>' +
            '</table>' +
            '</a>'
            );
            // When the DOM is ready, add event
            $(document).ready(function () {
                $('#centroid-checkbox-' + featureAttrs['ObjectID']).click(function (event) {
                    var objectId = $(this).attr('id').replace(/^\D+/g, '');
                    console.log(objectId + " was clicked");
                    if ($(this).is(':checked')) {
                        // Enable the 'Set Target' button
                        $('#btn-set-target').removeAttr('disabled');
                        // Disable all other choices
                        $('[id^="centroid-checkbox-"]').each(function (event) {
                            console.log("Picked up values for checkboxes");
                            if ($(this).attr('id') != ('centroid-checkbox-' + objectId)) {
                                $(this).attr('disabled', true);
                            }
                        });
                    }
                    else {
                        $('#btn-set-target').attr('disabled', 'disabled');
                        // Enable all text boxes
                        $('[id^="centroid-checkbox-"]').each(function () {
                            if (this.attr('id') !== ('centroid-checkbox-' + objectId)) {
                                this.removeAttr('disabled');
                            }
                        });
                    }
                });
            });

The problem I am having is that when I call $('[id^="centroid-checkbox-"]') it is returning undefined. However, at the time is gets called, there are about 30 "centroid-checkbox-XXXXX" checkboxes. What am I doing wrong here?

Answer 1

The $ function never returns undefined .

But this in the callback you pass to each is an element, not a jQuery object.

Which means you must use this.id instead of this.attr('id') and $(this).removeAttr('disabled') instead of this.removeAttr('disabled') (and you probably want this.disabled=false or $(this).prop('disabled', false) ).

Answer 2

objectId never gets defined because you need to quote enclose the regular expression you're using for replace():

var objectId = $(this).attr('id').replace(/^\D+/g, '');

should be:

var objectId = $(this).attr('id').replace('/^\D+/g', '');

DEMO: http://jsfiddle.net/4fUvn/8/