我不明白單擊 btn 文本時如何調用此函數。唯一有效的方法是(async () => { 我嘗試過這個$(document).ready(function() {    $('#demo').submit(function(e) {但不起作用。(async () => {const { value: file } = await Swal.fire({  title: 'Select image',  input: 'file',  inputAttributes: {    'accept': 'image/*',    'aria-label': 'Upload your profile picture'  }})if (file) {  const reader = new FileReader()  reader.onload = (e) => {    Swal.fire({      title: 'Your uploaded picture',      imageUrl: e.target.result,      imageAlt: 'The uploaded picture'    })  }  reader.readAsDataURL(file)}})()<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script><script src="https://cdn.jsdelivr.net/npm/sweetalert2@9"></script><button class="form-control cal "  id="demo">          Try me!        </button>