如何判斷乙個變數是陣列Array型別

var arr =[1

,2,3
]    console.
log(arr instanceof
array
)//true

var arr =[1

,2,3
]    console.
log(arr.constructor === array)
//true

array.isarray([1, 2, 3]);  // true

var num =

1var str =
'abc'
console.
log(object.prototype.tostring.()
)//[object object]
console.
log(object.prototype.tostring.
call
(str)
)//[object string]
console.
log(object.prototype.tostring.
call
(num)
)//[object number]

var arr= [1,1]

console.log(object.prototype.tostring.call(arr))

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