如何在添加新GIF前清除已搜索的历史GIF结果？

问题原因 #

你之前尝试的imagesEl.innerHTML = '';无效，是因为这个imagesEl是每次循环新创建的div，清空它根本不会影响页面上已存在的旧结果。真正需要清空的是存放所有GIF的父容器——imgContainer。

修复步骤 #

1. 在遍历GIF数据前，先清空imgContainer的内容，确保新搜索结果不会和旧内容叠加
2. 把hideLoader()移到forEach循环外面，等所有GIF渲染完成后再隐藏加载器，避免加载器提前消失
3. 删除循环里多余的imagesEl.innerHTML = '';，这行代码会刚创建完GIF就把它清空，反而导致显示异常

修改后的完整代码 #

JavaScript

const formEl = document.querySelector('form');
const loaderEl = document.querySelector('.loader');
const mainContainer = document.querySelector('.container')
const imgContainer = document.querySelector('.img-container')

function showLoader() {
    loaderEl.style.display = 'block';
}

function hideLoader() {
    loaderEl.style.display = 'none';
    loaderEl.innerHTML = '';
}


formEl.addEventListener('submit', (e) => {
    e.preventDefault();
    
    const input = formEl.querySelector('input[name="input"]').value;
    
    if (input.length >= 1){ 
        showLoader();
        performSearch(input);
    } else {
       hideLoader();   
    }
    e.target.reset();
    
});

function performSearch(search) {

    const gifCount = 10;
    const apiKey = 'VL071LzBWMdYPAyxErdI1d0YPs406vB5';
    const url = `https://api.giphy.com/v1/gifs/search?api_key=${apiKey}&q=${search}&limit=${gifCount}&offset=0&rating=pg-13&lang=en&bundle=messaging_non_clips`;

    fetch(url)
    .then((response) => response.json())
    .then((info) => {
        console.log(info.data)
        const giftData = info.data;
        
        // 关键：先清空容器内的旧内容
        imgContainer.innerHTML = '';
        
        giftData.forEach((e) => {
            // 创建存放单张GIF的容器
            const imagesEl = document.createElement('div');
            imagesEl.classList.add('images');
            // 创建GIF图片元素
            const img = document.createElement('img');
            img.setAttribute("src", e.images.fixed_height_downsampled.url);
            
            // 将图片添加到容器，再把容器添加到页面的父容器中
            imagesEl.appendChild(img);
            imgContainer.appendChild(imagesEl);
        });
        
        // 所有GIF渲染完成后再隐藏加载器
        hideLoader();
    });
};

CSS

* {
    padding: 0;
    margin: 0;
    box-sizing: border-box;
}

body {
    background-color: #7C9D96;
    display: flex;
    align-items: center;
    justify-content: center;
    font-family: 'Roboto';
}

.container {
    position: relative; 
    display: flex;
    align-items: center;
    flex-direction: column;
    max-width: 1600px;
    height: 100vh;
    margin: auto;
    padding: 50px 0;
}

input {
    height: 80px;
    width: 800px;
    font-size: 20px;
    padding-left: 10px;
    border: none;
    outline: none;
}

input:focus {
    color: #353535;
}

.search-container {
    margin: 0 50px;
    width: 100%;
}

.btn {
    height: 80px;
    width: 200px;
    border: none;
    cursor: pointer;
    font-size: 20px;
    color: #353535;
}

.btn:active {
    background-color: #749BC2;
    transition: .3s;
}

.loader {
    position: absolute;
    top: 40%;
    left: 40%;
    display: none;
    width: 200px;
    height: 200px;
    border: 30px solid #0B666A;
    border-radius: 50%;
    border-bottom: 30px solid white;
    animation: rotate .3s infinite linear;
}

@keyframes rotate {
    0% {
        rotate: 0deg;
    }
    100% {
        rotate: 360deg;
    }
}

.img-container {
    width: 100%;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    margin: 20px;
    align-items: center;
    justify-content: center;
}

.images {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 5px;
    border-radius: 5px;
    margin: 15px;
    padding: 20px;
    background-color: #F4F2DE;
}

.images:hover {
    padding-bottom: 50px;
    transition: .5s;
}

.images img {
    width: 100%;
    object-fit: contain;
    height: 150px;
}

HTML

<div class="container">
    <div class="search-container">
        <form>
            <input type="text" name="input" class="text" placeholder="Ex. Happy" autocomplete="off">
            <button class="btn">Search</button>
        </form>
    </div>
    <div class="loader"></div>
    <div class="img-container">
        <!-- 动态GIF内容会在这里生成 -->
    </div>
</div>

内容的提问来源于stack exchange，提问作者Gad Ashell