题解 | #购物车#

线下测试没有问题，请大家帮我看下，私信我有偿！

var tagInput = {
    isInited: false,
    init: init,
    bindEvent: bindEvent,
    addTag: addTag,
    removeTag: removeTag
};
tagInput.init();

function init() {
    var that = this;
    if (that.isInited) return;
    that.isInited = true;
    // 请修改这一行代码，保存class为js-input的输入框的dom元素引用
    that.input = document.getElementsByClassName('js-input')[0];
    that.bindEvent();
}

function bindEvent() {
    var that = this;
    var input = that.input;
    if (!input) return;
    input.addEventListener('keydown', function (event) {
        // 请修改这一行代码，判断用户是否按了回车键
        var isEnter = event.keyCode===13;
        // 请修改这一行代码，判断用户是否按了删除键
        var isDelete = event.keyCode===8;

        (isEnter || isDelete) && event.preventDefault();
        isEnter && that.addTag();
        isDelete && that.removeTag();
    });
    input.parentNode.addEventListener('click', function () {
        input.focus();
    });
}

function addTag() {
var that=this
var input=that.input
var span=document.createElement('span')
span.classList.add('tag')
span.innerText=input.value.trim()
var tags=document.querySelectorAll('.tag')
var test=[]
tags.forEach((item)=>{
    test.push(item.innerText)
})
if(test.indexOf(span.innerText)==-1){
    if(span.innerText==''){
       input.value=''
    return ;
    }else{
       input.parentNode.insertBefore(span,input)
    }
}

input.value=''
}

function removeTag() {
var that=this
var input=that.input
if(!input.value.trim()){
    var parent=input.parentNode

if(parent.children.length>1){
    parent.removeChild(parent.children[parent.children.length-2])
}
}else{
    input.value=input.value.slice(0,-1)
}

}