How to empty an array in JavaScript?

When I write pathfinding codes in JavaScript, I ran into this problem: how to empty the array?

Methods

  • Method 1
1
array = []
  • Method 2
1
array.length = 0
  • Method 3
1
array.splice(0, array.length)
  • Method 4
1
2
3
while (array.length > 0) {
array.pop()
}

Difference between Method 1 and the others

Method 1 only reassign a:

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2
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8
let a = [1, 2, 3]
let b = a

// empty a, but doesn't affect b
a = []

console.log('a =', a)
console.log('b =', b)

Method 2, 3, 4, will empty multiple variables referencing the same object:

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3
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let a = [1, 2, 3]
let b = a

// empty a and b
a.length = 0

console.log('a =', a)
console.log('b =', b)

More

See https://github.com/UMU618/js-empty-array#example

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