访问动态表单数组 HTML/Bootstrap/Javascript

<form id="loanform" role="form" autocomplete="off" method="post" onsubmit="hello()">
                <div class="entry input-group col-xs-3">How much extra money can you pay per month?
                    <input class="form-control" name="extra" type="text" placeholder="Extra/month" />
                </div>
                <br>
                <div class="entry input-group col-xs-9">
                    <div class="col-xs-3">
                        <input class="form-control" name="balances['+current+']" id="balances'+current+'" type="text" placeholder="Loan Balance" required="required" />
                    </div>
                    <div class="col-xs-3">
                        <input class="form-control" name="rates['+current+']" id="rates'+current+'" type="text" placeholder="Interest Rate" required="required" />
                    </div>
                    <div class="col-xs-3">
                        <input class="form-control" name="payments['+current+']" id="payments'+current+'" type="text" placeholder="Minimum Payment" required="required" />
                    </div> <span class="input-group-btn col-xs-1">
                                   <button class="btn btn-success btn-add" type="button">
                                           <span class="glyphicon glyphicon-plus"></span>
                    </button>
                    </span>
                </div>
        </div>
        <div class="input-group-btn">
            <div class="col-xs-5">
                <button type="submit" class="btn btn-primary">Submit</button>
            </div>
        </div>
        </form>

$(function () {
$(document).on('click', '.btn-add', function (e) {
    e.preventDefault();
    var controlForm = $('.controls form:first'),
        currentEntry = $(this).parents('.entry:first'),
        newEntry = $(currentEntry.clone()).appendTo(controlForm);
    newEntry.find('input').val('');
    controlForm.find('.entry:not(:last) .btn-add')
        .removeClass('btn-add').addClass('btn-remove')
        .removeClass('btn-success').addClass('btn-danger')
        .html('<span class="glyphicon glyphicon-minus"></span>');
}).on('click', '.btn-remove', function (e) {
    $(this).parents('.entry:first').remove();
    e.preventDefault();
    return false;
});

function hello() {
alert("Hello has been called");
var bal = document.getElementById('balances0').value;
alert(bal);
alert("function over");

你的代码中存在一些问题：

1. hello不是一种全局方法。您可以像这样添加它window.hello = hello;然后就可以访问它了。但我建议使用$(...).submit(...)
2. id="balances'+current+'"在 HTML 中无效。这不会被执行。
3. 我会为每个输入字段添加类，并data-index以便于访问。
4. 将表单存储在 DOM 中并不好，因为您无法保持索引干净。最好在 JS 中创建表单作为数组，并在每次 +/- 单击时更新此数组。我的意思是，例如，如果您添加了两行，那么第二行将具有data-index=1，如果您之前使用索引 0 删除 DOM 元素并重新添加一行，那么您的列表中没有索引 0。

你可以在这里找到更新的jsFiddle。

稍后我将改进代码以显示我对数组方法的含义。

---

更新 08.03.2015

请在此jsFiddle和下面找到更新的代码。

我添加了以下代码：

• 跟踪数组中的表单元素
• 将每行的表单元素作为模板存储在<script type="text/template"/>标记中。
• 将数组项的索引添加到每个表单输入的 name 属性
• 将对 $.submit(...) 内部表单数据的访问更改为$.serializeArray()
添加新行后，向
• 新输入行添加了焦点更改。

我认为这应该是您现在计算应用程序的一个很好的起点。

$(function() {
    //console.log($('#template_add_form'));
    var clone = function(tmpl) {
            return $((tmpl.clone()).html())
        },
        $template = $('#template_add_form'),
        formArray = [ clone($template) ], // init array with first row
        $formEntries = $('#entries');
    
    $(document).on('click', '.btn-add', function() {
        //console.log('clicked');
        formArray.push(clone($template));
        updateForm();
        // set focus to adding row = last element in array
        $(formArray).last()[0]
            .find('input')
            .first()
            .focus();
    });
    
    // remove not working yet
    
    $(document).on('click', '.btn-remove', function(evt) {
        var id;
        // iterate over formArray to find the currently clicked row
        $.each(formArray, function(index, row) {
            //console.log(index, row.has(evt.currentTarget).length);
            if ( row.has(evt.currentTarget).length == 1 ) {
                //console.log(row.has(evt.currentTarget));
                id = index; // click target in current row
                return false; // exit each loop
            }
        });
        
        //console.log('clicked', id);
        formArray.splice(id, 1);
        updateForm();
    });
    
    var updateForm = function() {
        // redraw form --> problem values are cleared!!
        //console.log(formArray);
        var lastIndex = formArray.length - 1,
            name; // stores current name of input
        
        $formEntries.empty(); // clear entries from DOM becaue we re-create them
        $.each(formArray, function(index, $input) {
            //console.log(index, $input);
            // update names of inputs and add index
            //console.log('inputs', $input.find('input'));
            $.each($input.find('input'), function(inputIndex, input) {
                name = $(input).attr('name').replace(/'d+/g, ''); // remove ids
                $(input).attr('name', name + index);
            });
            
            if (index < lastIndex) {
                // not last element --> change button to minus
                //console.log($input.find('.btn-add'));
                $input.find('.btn-add')
                     .removeClass('btn-add').addClass('btn-remove')
                     .removeClass('btn-success').addClass('btn-danger')
                     .html('<span class="glyphicon glyphicon-minus"></span>');
            }
            
            $formEntries.append($input);
        });
    };
    
    updateForm(); // first init. of form
    
    $('form#loanform').submit(function(evt) { 
        evt.preventDefault();
        var fields = $(this).serializeArray();
        $.each(fields, function(index, field) {
            //console.log(field.name);
            if ( field.name == 'extra' ) {
                console.log('extra', field.name, field.value);
            }
            if ( field.name.contains('balance') ) 
            {   // field.name contains balance
                console.log('balance', field.name, field.value);
                // now you can do your calculation
            }
            if ( field.name.contains('rate') )
            {   // field.name contains balance
                console.log('rate', field.name, field.value);
                // now you can do your calculation
            }
            if ( field.name.contains('payment') )
            {   // field.name contains balance
                console.log('payment', field.name, field.value);
                // now you can do your calculation
            }
        });
    });
});

body {
    .entry:not(:first-of-type) {
        margin-top: 10px;
    }
    .glyphicon {
        font-size: 12px;
    }
}

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script src="http://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/js/bootstrap.min.js"></script>
<link href="http://maxcdn.bootstrapcdn.com/bootstrap/3.3.2/css/bootstrap.min.css" rel="stylesheet"/>
<script id="template_add_form" type="text/template">
    <div class = "entry input-group col-xs-9">
        <div class = "col-xs-3">
            <input class = "form-control" name="balance" type = "text" 
                   placeholder = "Loan Balance" required = "required"/>
        </div>
        <div class="col-xs-3">
            <input class="form-control" name="rate" type="text" placeholder="Interest Rate" required="required" />
        </div>
        <div class="col-xs-3">
            <input class="form-control" name="payment" type="text" placeholder="Minimum Payment" required="required"/>
        </div> 
        <span class="input-group-btn col-xs-1">
            <button class="btn btn-success btn-add" type="button">
                <span class="glyphicon glyphicon-plus"></span >
            </button>
        </span>
    </div>
</script>
<div class="container">
    <div class="row">
        <div class="control-group" id="fields">
            <label class="control-label" for="field1">
                 <h3>Enter your loans below</h3>
            </label>
            <div class="controls">
                <form id="loanform" role="form" autocomplete="off" method="post">
                    <div class="entry input-group col-xs-3">How much extra money can you pay per month?
                        <input class="form-control" name="extra" type="text" placeholder="Extra/month" />
                    </div>
                    <br>
                    <div id="entries"></div>
            </div>
            <div class="input-group-btn">
                <div class="col-xs-5">
                    <button type="submit" class="btn btn-primary">Submit</button>
                </div>
            </div>
            </form>
            <br> <small>Press <span class="glyphicon glyphicon-plus gs"></span> to add another loan</small>
        </div>
    </div>
</div>