Javascript 如何在待办事项列表的条目左侧显示下拉选项？

谢谢你的关注。这是代码笔：

我试图让用户从下拉列表中选择一个数字，并在“输入到输入”框中键入一个单词，当他们输入回车时，他们会看到一个条目，中间有他们要做的文本，他们在条目左边选择。

如何做到这一点？我不太擅长Javascript，大部分时间都在修补预制的代码笔，拼命地想把代码拼凑起来

HTML:

JS:

---

多谢各位

我已在表单提交事件处理程序中更新了部分代码：

$('form').submit(function () {
        if (input.val() !== '') {
            var inputVal = input.val(),
                activeNumber = $('.ActiveListItem').text(); // gets the selected number

            // adds the selected number on before the inputValue:
            ul.append('<li>' + activeNumber + ' ' +inputVal + '<a href="">X</a></li>');
            if (ul.hasClass('inactive')) {
                ul.removeClass('inactive')
                    .addClass('active');
            }
        };
        input.val('');
        return false;
    });

---

我已将您的示例放在此处：

您可以在上运行它，并将链接放在您的问题中。我下次会这样做，很高兴知道=]

/*adder*/

@import url(http://fonts.googleapis.com/css?family=Open+Sans:400, 300, 600);


 * {
    padding:0;
    margin:0;
}


html {
 background:teal;
}


body {
    /*background:url('https://snap-photos.s3.amazonaws.com/img-thumbs/960w/4657039731.jpg');*/
}


a {
    color: #D9D9D9;
    text-decoration: none;
}
a:active, a:hover {
    text-decoration: underline;
}



#heady {
    text-align: center;
    width:100%;
    height:75px;
    background-color:#222;                       /*Back Colors*/
    font-family: Tahoma;
    font-size: 16px;
    color:white;
    position:relative; 
}

#wrapper {
    text-align: center;
    width:1000px;
    height:1000px;
    margin-left:auto;
    margin-right:auto;
    background-color:teal;                       /*Back Colors*/
    font-family: Tahoma;
    font-size: 16px;
    position:relative; 
}


#feety {
    text-align: center;
    width:100%;
    height:100px;
    background-color:darkslateblue;                       /*Back Colors*/
    font-family: Tahoma;
    font-size: 16px;
    color:white;
    position:relative; 
}










/* clearfix */
/**
 * For modern browsers
 * 1. The space content is one way to avoid an Opera bug when the
 *    contenteditable attribute is included anywhere else in the document.
 *    Otherwise it causes space to appear at the top and bottom of elements
 *    that are clearfixed.
 * 2. The use of `table` rather than `block` is only necessary if using
 *    `:before` to contain the top-margins of child elements.
 */
.cf:before,
.cf:after {
    content: " "; /* 1 */
    display: table; /* 2 */
}

.cf:after {
    clear: both;
}

.cf {
   * zoom: 1;
}


ul.navbar {

  background:white; 
  border-style:solid;
  border-color:gray;
  border-width:1px;
  width: 200px;
  border-radius: 4px;

}


.ActiveListItem:after {
    content: "\25BC\00a0\00a0";                        /*carat and spaces*/
    float:right;
    font-weight:900;
    padding: 0px 0px;
    font-size:100%; 
    line-height:20px;             /*keeps carat in center of text*/
}




ul.navbar li a.ActiveListItem {
    background:white !important;
    color:black;
    border-style:solid;
    border-color:white;
    border-radius:4px;
    padding:3px 5px !important;
    font-weight:normal !important;
    margin-left:14px;/* got the activeitem centered with the list text this way*/
    margin-right:0px;

}

ul.navbar li {
    position: relative;
}

ul.navbar li a {
    display: block;
    color: white;
    padding:10px 5px;
    text-decoration:none;
    transition: all .2s ease-in;

}

ul.navbar li a:hover,
ul.navbar li:hover > a {
    background:#a6d0e1; /*Leaving for now, but keep in mind things bold slowly when you change this to gradient*/
    color: #333;
    font-weight:900;

}

    ul.navbar li ul {
        margin-top: 1px;
        position: absolute;
        background: #222;
        font-size: 14px;
        min-width: 200px;
        display: none;
        z-index: 99;
        box-shadow: inset 0 2px 3px rgba(0,0,0,.6),
        0 5px 10px rgba(0,0,0,.6);
    }

ol, ul { list-style: outside none none; }

.hidden { display: none; }







/*Lister*/



.container {
    width: 60%;
    margin: 0px auto;
}

form {  }

input,
ul {
    background: #eee;
    border-radius: 5px;
    width: 100%;
    box-sizing: border-box;
    font-family:"Tahoma";
}

input {
    padding: 10px 10px 10px 20px;
    border: 1px solid #ccc;
}

.lister ul {
    list-style: square inside;
    padding: 10px;
}

.active { border: 1px solid #ccc; }

.inactive { display: none; }

.lister li {
    padding: 10px;
    font-weight: 600;
    color: #34495e;
}

.lister li:nth-child(odd) {
    background: #dadfe1;
    border-radius: 5px;
}

.lister li > a {
    float: right;
    text-decoration: none;
    color: #22313f;
    font-weight: bold;
    transition: all .2s ease-in-out;
}

.lister li > a:hover {
    font-size: 110%;
    color: #c0392b;
}


.lister li:before {
    content: "#";                        /*carat and spaces*/
    float:left;
    font-weight:900;
    padding: 0px 0px;
    font-size:100%; 
    line-height:20px;             /*keeps carat in center of text*/
}

// sub menus identification
$(function() {
  $('.navbar ul li a').click(function(){  
    $('.navbar > li:first-child > a').text($(this).text());
    $('.navbar > li > ul').addClass('hidden');
    $('.navbar li ul').slideToggle(100);
  });
  $('.navbar > li').mouseenter(function(){
    $(this).find('ul').removeClass('hidden');
  });
  $('.ActiveListItem').click(function(){        
    $('.navbar li ul').slideToggle(300);
  });    
});









//newList

$(document).ready(function() {  

    var ul = $('.lister ul'),
        input = $('input');

    input.focus();  

    $('form').submit(function () {
        if (input.val() !== '') {
            var inputVal = input.val();
            ul.append('<li>' + inputVal + '<a href="">X</a></li>');
            if (ul.hasClass('inactive')) {
                ul.removeClass('inactive')
                    .addClass('active');
            }
        };
        input.val('');
        return false;
    });

    ul.on('click', 'a', function (e) {
        e.preventDefault();
        $(this).parent().remove();

        if (ul.children().length == 0) {
            ul.removeClass('active')
                .addClass('inactive');
            input.focus();  
        }
    });

});

$('form').submit(function () {
        if (input.val() !== '') {
            var inputVal = input.val(),
                activeNumber = $('.ActiveListItem').text(); // gets the selected number

            // adds the selected number on before the inputValue:
            ul.append('<li>' + activeNumber + ' ' +inputVal + '<a href="">X</a></li>');
            if (ul.hasClass('inactive')) {
                ul.removeClass('inactive')
                    .addClass('active');
            }
        };
        input.val('');
        return false;
    });