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This article mainly introduces the relevant knowledge of "how js deletes the last element in an array". The editor shows you the operation process through an actual case. The method of operation is simple and fast, and it is practical. I hope this article "how to delete the last element of an array by js" can help you solve the problem.

1. Merge array: concat ()

Grammar

String.concat (string1, string2, … , stringX)

Example

Var arr = [1, 2, 3, 7]; arr.concat ([5, 5, 6, 7)) / / [1, 2, 3, 4, 4, 5, 6, 7] 2, adding elements at the end: push ()

Grammar

Array.push (item1, item2, … , itemX)

Example

Let a = [1JEI 2jue 3]; let item = a.push ('end'); / / 4console.log (a); / / [1JEI 2JI 3Jing']

3. Delete the last element in an array: pop ()

Grammar

Array.pop ()

Example

Var a = [1JI 2jue 3]; var b = a.pop () console.log (b) / / 3

4. Add one or more elements at the beginning: unshift ()

Grammar

Array.unshift (item1,item2, … , itemX)

Example

Let arr = [2, 3, 1, 9, 7, 5, 8, 22]; console.log (arr); arr.unshift ("new1", "new2", "new3"); console.log (arr); output: [2, 3, 1, 9, 7, 5, 8, 22] ['new1',' new2', 'new3', 2, 3, 1, 9, 7, 5, 8, 22]

5. Array sorting: sort ()

Grammar

Array.sort (sortfunction)

Example

Var a = [3, 1, 5, 5, 2]; var b = a.sort () console.log (b) / / [1, 2, 3, 4, 5]

6. Add / remove array elements: splice ()

Grammar

Array.splice (index,howmany,item1, … , itemX)

Example

Let arr = [2, 3, 1, 9, 7, 5, 8, 22]; console.log (arr); console.log (arr.splice (2,3, "this is a newly added element"); console.log (arr); output result: [2, 3, 1, 9, 7, 5, 8, 22] [1, 9, 7] [2, 3, 'this is a newly added element', 5, 8, 22]

7. Reverse the order of the elements in the array: reverse ()

Grammar

Array.reverse ()

Example

Let a = [1rem 2je 3]; a.reverse (); console.log (a); / / [3je 2jue 1] about "how js deletes the last element in an array", thank you for your reading. If you want to know more about the industry, you can follow the industry information channel. The editor will update different knowledge points for you every day.

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