arraybuffer类型数据转为json

let content = file.data;//arraybuffer类型数据
let resBlob = new Blob([content])
let reader = new FileReader()
reader.readAsText(resBlob, "utf-8")
reader.onload = () => {
  let res = JSON.parse(reader.result)
  console.log(JSON.parse(reader.result))
}