for_in和for_of的区别

const arobj =
  100:1,
  d:2,
  a:9,
  1:3,
  5:99,
  b:8
}
Object.prototype.fun =()=>{}
arobj.name = "lallala"
const arr=[1,2,4,8,9,10]
Array.prototype.method ()=>{}
arr.name ="bababa";
for (const item in arobj){
  console.log(arobj[item])//3 99 1 2 9 8 lallala ()=>{
}
for (const item in arr){
  console.log(item)//0 1 2 3 4 5 name method fun
}
for (const item of arobj){
  console.log(item)//Uncaught TypeError:arobj is not iterable
}
for (const item of arr){
  console.log(item)//1 2 4 8 9 10
}