{
  const sleep = ms => {
    const d = $.Deferred()
    
    setTimeout(d.resolve, ms)
    
    return d.promise()
  }
  
  $.when(sleep(300), sleep(500), sleep(800)).done(() => {
    console.log('成功')
  })
}

{
  const sleep = ms => new Promise(resolve => setTimeout(resolve, ms))
  
  Promise.all([sleep(300), sleep(500), sleep(800)]).then(() => {
    console.log('成功')
  })
}