예제
<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <div class="image-upload">
        <label for="file-input">
            <img src="./upload.jpg" />
        </label>
        
        <input id="file-input" type="file" multiple />
    </div>
    
    <div id="preview-container"></div>
    <script>
        
        document.querySelector('#file-input').addEventListener('change', e => {
            
            const preview = document.querySelector('#preview-container');
            
            preview.innerHTML = '';
            
            const file = e.currentTarget.files;
            console.log(file);
            
            Array.from(file).forEach((v, i) => {
                console.log(v);
                
                const img = URL.createObjectURL(v);
                
                
                
                const div = document.createElement('div');
                div.classList.add('previews');
                div.style.backgroundImage = 'url(' + img + ')';
                
                
                preview.appendChild(div);
            });
        });
    </script>
</body>
</html>