create random array javascript code example

Example 1: javascript get random array value

//get random value from array
var colors = ["red","blue","green","yellow"];
var randColor = colors[Math.floor(Math.random() * colors.length)];

Example 2: javascript generate array of random different numbers

var arr = [];
while(arr.length < 8){
    var r = Math.floor(Math.random() * 100) + 1;
    if(arr.indexOf(r) === -1) arr.push(r);
}
console.log(arr);

Example 3: javascript generate random array

//This example is to generate an array with 40 random elements, with random values from 0 to 39 

for (var a=[],i=0;i<40;++i) a[i]=i;

// http://stackoverflow.com/questions/962802#962890
function shuffle(array) {
  var tmp, current, top = array.length;
  if(top) while(--top) {
    current = Math.floor(Math.random() * (top + 1));
    tmp = array[current];
    array[current] = array[top];
    array[top] = tmp;
  }
  return array;
}

a = shuffle(a);

Example 4: get random item from array javascript

let items = [12, 548 , 'a' , 2 , 5478 , 'foo' , 8852, , 'Doe' , 2145 , 119];

let  randomItem = items[Math.floor(Math.random() * items.length)];