SoFunction
Updated on 2025-03-04

How to quickly create an array of 1 to 100 using JavaScript

Code example:

let arr = []
// push methodfor(let i = 1,len=100;i<=100;i++){(i)}
//  or
//Cyclic assignmentfor(let i = 1,len=100;i<=100;i++){arr[i-1]=i}
// () method There will be a little optimization later({length:101}, (v,k) => k)// or (Array(101), (v,k) =>k);
(Array(101).keys())
(0,1)

// Use recursive implementation// Current value// Maximum lengthlet arr = []
function setArray(current,maxLength,arr){
  if(<maxLength){
    arr[current-1] = current
    setArray(++current,maxLength,arr)
  }else{
      (i=>i)// Remove false values ​​empty  }
}
setArray(1,100,arr)
// I don't know if there are any performance issues
// I saw some methods online, which are quite fun, but I don't know the source
// 1
let arr = Array(100).toString().split(',').map((item,index)=>index)// 0-> 99

// 2
let i = 0;
let timer = setInterval(function(){
  arr[i] = i++;
  if(i>=100){
    clearInterval(timer);
    (arr);
  }
},1); // 0-> 99

// 3
((null, {length:100})).map(item=>+item);// 0-> 99

// 4
[...Array(100).keys()]// 0-> 99
[...({length:100}).keys()]// 0-> 99

// mdn see sequence generator (specified range)const range = (start, stop, step) => ({ length: (stop - start) / step + 1}, (_, i) =>  + (i * step));

range(1,100,1)// 1-> 100

//Optimize what I wrote above({length:100},(_, i)=>1+(i)) // 1-> 100

What I think looks most comfortable is:({length:100},(_, i)=>1+(i))

Prerequisite knowledge:

()

(arrayLike[, mapFn[, thisArg]])

arrayLike

A pseudo-array object or iterable object that you want to convert to an array.

mapFnOptional

If this parameter is specified, each element in the new array executes the callback function.

thisArgOptional

Optional parameters, execute callback functionmapFnhourthisObject.

Return value

A new oneArrayExample.

usage:

  • String Generate Array
  • Set Generate Array
  • Map Generate Array
  • Class Array Generate Array

Example: Generate an array from a map

const map = new Map([[1, 2], [2, 4], [4, 8]]);
(map);
// [[1, 2], [2, 4], [4, 8]]

const mapper = new Map([['1', 'a'], ['2', 'b']]);
(());
// ['a', 'b'];

(());
// ['1', '2'];

other:

({length: 100}) or  (Array(100))

// Will be generated(100) [undefined,..., undefined]

Array instance method keys()

keys() is a new traversal of key names added in ES6, returning a traversal object

apply(thisArg, [argsArray])

apply(thisArg, [argsArray])

parameter

thisArg

Required. existfuncUsed when function runsthisvalue. Please note thatthisProbably not the actual value seen by the method: if this function is inNon-strict modeNext, specify asnullorundefinedIt will be automatically replaced with a pointing to a global object, and the original value will be wrapped.

argsArray

Optional. An array or class array object, where the array element is passed tofuncfunction. If the value of this parameter isnullorundefined, it means that no parameters need to be passed in. Starting with ECMAScript 5, you can use class array objects.

Return value

The call is specifiedthisThe result of a function with values ​​and parameters.

Supplement: Implement randomly obtaining non-repetitive arrays of 1-100 in js

    <script type="text/javascript">
        function getArr() {
            var i = 0;
            var arr = new Array();
            var p;
            while (i < 100) {
                //Generate random numbers                var p = (() * 100 + 1)
                if ((p) == -1) {
                    arr[i] = p;
                    i++;
                }
            }
            return arr;
        }
    </script>

Summarize

This is the end of this article about how to quickly create a 1 to 100 array using JavaScript. For more related JS content, please search for my previous article or continue browsing the related articles below. I hope you will support me in the future!