展开对象为属性 ...

const addForm = document.querySelector('.add-form')
    const formdata = serialize(addForm, { hash: true, empty: true })


    axios({
        url: 'https://hmajax.itheima.net/api/books',
        method: 'POST',

        data: {
            //这里进行展开 ...
            ...formdata,
            creator
        }
    }).then(res => {
        console.log(res.data)

        renderdata()
        // addForm.reset()
        addModal.hide()

    })