How js inserts elements at the head or tail of an array

This article mainly introduces "how js inserts elements in the head or tail of an array". In daily operation, I believe many people have doubts about how js inserts elements in the head or tail of an array. Xiaobian consulted all kinds of data and sorted out simple and easy-to-use operation methods. I hope it will be helpful to answer the doubts of "how js inserts elements in the head or tail of an array". Next, please follow the editor to study!

1. Unshift () inserts an element at the beginning of the array and appends one or more parameter values to the head of the array.

Array.unshift (element 1, element 2,..., element X)

Example

Var a = [0]; / / defines the array console.log (a); / / returns [0] a.unshift (1Power2); / / adds two elements console.log (a) at one time; / / returns [1SCOO] var a = [0]; a.unshift (1); / / adds the element 1a.unshift (2); / / adds the element 2console.log (a); / / returns [2jfl 0] inserts the element at the end of the array

2. Push () appends one or more parameter values to the end of the array.

Array.push (element 1, element 2,..., element X)

3. Concat () adds the elements of one or more arrays as parameters to the end of the specified array.

You can join two or more arrays.

Var a = [1Jing 2jue 3]; var b = [4,5,6]; var c = [7je 8]; var d = a.concat (bReed c); console.log (d). At this point, the study on "how js inserts elements into the head or tail of an array" is over, hoping to solve everyone's doubts. The collocation of theory and practice can better help you learn, go and try it! If you want to continue to learn more related knowledge, please continue to follow the website, the editor will continue to work hard to bring you more practical articles!