Jquery - 删除最后一个追加项

Question

诚然，我对Jquery一点也不熟悉，尽管它是我需要学习的任务。我目前正在处理一个项目，该项目需要类似于发票上的添加/删除功能。

我希望能够在附加的最后一个项目中添加"删除"功能，以防出现错误等

$(document).ready(function() {
var currentItem = 1;
$('#addnew').click(function(){
currentItem++;
$('#items').val(currentItem);
var strToAdd = '<br>Product: <select class="form" name="Product'+currentItem+'" id="product'+currentItem+'" ><option value="Aramax Classic Tobacco">Aramax Classic Tobacco</option><option value="Aramax Energy Drink">Aramax Energy Drink</option></select>    Nicotine: <select class="form" name="nicotine'+currentItem+'" id="nicotine'+currentItem+'"> <option value="N/A">n/a</option><option value="3mg">3mg</option><option value="6mg">6mg</option><option value="12mg">12mg</option></select>    Quantity:<input class="form3" name="qty'+currentItem+'" id="qty'+currentItem+'" type="number" /><br>';
$('#data').append(strToAdd);
});
});
$('#delete').on('click', function() {
$('#items').parents("br").remove();
});
//]]>
</script><div class="form2">
<form method="POST" action="invoicereg.php" id="data" name="sub">
Product:
<select class="form" name="product1" id="product1">
<option value="Aramax Classic Tobacco">Aramax Classic Tobacco</option>
<option value="Aramax Energy Drink">Aramax Energy Drink</option>
</select>
Nicotine:
<select class="form" name="nicotine1" id="nicotine1">
<option value="N/A">n/a</option>
<option value="3mg">3mg</option>
<option value="6mg">6mg</option>
<option value="12mg">12mg</option>
</select>
Quantity:<input class="form3" type="number" id="qty1" name="qty1"></input><br>
</form>
<br>
<input class="button" type="button" id="addnew" name="addnew" value="Add new item" /> 
<input type="hidden" form="data" id="items" name="items" value="1" />
<input class="button" type="button" id="delete" name="delete" value="Remove" /> 
<input class="button" type="submit" form="data" value="SUBMIT">
</div>
</div>
</body>
</html>

如果有人可以向我展示和/或解释这是如何完成的，我们将不胜感激。 问候

Answer 1

我用<div>说唱了您的表单内容和您添加的内容.

然后你可以做$('#data > div').last().remove();

#data是表单的 ID。

#data > div将选择作为form的第一个孩子的所有<div>。

.last()选择最后一个元素。

请注意，如果您想在表单中保留至少 1 个元素，您可以这样做：

if ($('#data > div').length > 1) {
$('#data > div').last().remove();
}

$(document).ready(function() {
var currentItem = 1;
$('#addnew').click(function(){
currentItem++;
$('#items').val(currentItem);
var strToAdd = '<div><br>Product: <select class="form" name="Product'+currentItem+'" id="product'+currentItem+'" ><option value="Aramax Classic Tobacco">Aramax Classic Tobacco</option><option value="Aramax Energy Drink">Aramax Energy Drink</option></select>    Nicotine: <select class="form" name="nicotine'+currentItem+'" id="nicotine'+currentItem+'"> <option value="N/A">n/a</option><option value="3mg">3mg</option><option value="6mg">6mg</option><option value="12mg">12mg</option></select>    Quantity:<input class="form3" name="qty'+currentItem+'" id="qty'+currentItem+'" type="number" /><br></div>';
$('#data').append(strToAdd);
});
});
$('#delete').on('click', function() {
if ($('#data > div').length > 1) {
$('#data > div').last().remove();
}
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
</script><div class="form2">
<form method="POST" action="invoicereg.php" id="data" name="sub">
<div> 
Product:
<select class="form" name="product1" id="product1">
<option value="Aramax Classic Tobacco">Aramax Classic Tobacco</option>
<option value="Aramax Energy Drink">Aramax Energy Drink</option>
</select>
Nicotine:
<select class="form" name="nicotine1" id="nicotine1">
<option value="N/A">n/a</option>
<option value="3mg">3mg</option>
<option value="6mg">6mg</option>
<option value="12mg">12mg</option>
</select>
Quantity:<input class="form3" type="number" id="qty1" name="qty1"></input><br>
</div>
</form>
<br>
<input class="button" type="button" id="addnew" name="addnew" value="Add new item" /> 
<input type="hidden" form="data" id="items" name="items" value="1" />
<input class="button" type="button" id="delete" name="delete" value="Remove" /> 
<input class="button" type="submit" form="data" value="SUBMIT">
</div>
</div>
</body>
</html>

Answer 2

像<div class="items">yourcode</div>一样在所有div上使用一些。然后用$('.items').last()涂抹.remove()

$(document).ready(function() {
var currentItem = 1;
$('#addnew').click(function() {
currentItem++;
$('#items').val(currentItem);
var strToAdd = '<br><div class="items">Product: <select class="form" name="Product' + currentItem + '" id="product' + currentItem + '" ><option value="Aramax Classic Tobacco">Aramax Classic Tobacco</option><option value="Aramax Energy Drink">Aramax Energy Drink</option></select>    Nicotine: <select class="form" name="nicotine' + currentItem + '" id="nicotine' + currentItem + '"> <option value="N/A">n/a</option><option value="3mg">3mg</option><option value="6mg">6mg</option><option value="12mg">12mg</option></select>    Quantity:<input class="form3" name="qty' + currentItem + '" id="qty' + currentItem + '" type="number" /><br></div>';
$('#data').append(strToAdd);
});
});
$('#delete').on('click', function() {
$('.items').last().remove()
});

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="form2">
<form method="POST" action="invoicereg.php" id="data" name="sub">
<div class="items">
Product:
<select class="form" name="product1" id="product1">
<option value="Aramax Classic Tobacco">Aramax Classic Tobacco</option>
<option value="Aramax Energy Drink">Aramax Energy Drink</option>
</select>
Nicotine:
<select class="form" name="nicotine1" id="nicotine1">
<option value="N/A">n/a</option>
<option value="3mg">3mg</option>
<option value="6mg">6mg</option>
<option value="12mg">12mg</option>
</select>
Quantity:
<input class="form3" type="number" id="qty1" name="qty1"></input>
<br>
</div>
</form>
<br>
<input class="button" type="button" id="addnew" name="addnew" value="Add new item" />
<input type="hidden" form="data" id="items" name="items" value="1" />
<input class="button" type="button" id="delete" name="delete" value="Remove" />
<input class="button" type="submit" form="data" value="SUBMIT">
</div>
</div>

Answer 3

最好将添加的项目包装在div 中，例如：
<div class="added-item"></div>
然后单击删除按钮时，您必须var added_items = $('.added-item');
找到所有这些添加的项目
，然后删除最后一个元素
added_items.last().remove();