解决formData使用append追加后仍为空

const formData = new FormData()
console.log(file.value)
formData.append('file', file.value)
console.log(formData)

解决: 需要用formData.get("键")的方法获取值

const formData = new FormData()
console.log(file.value)
formData.append('file', file.value)
console.log(formData.get('file'))