This question already has answers here:
How do I check if an array includes a value in JavaScript?
(60 answers)
Closed 10 years ago.
var a=new Array;
for (j=0;j<=10;j++) {
a[j]=Math.floor(Math.random()*99)+2
}
var check=Math.floor(Math.random()*99)+2
So how do I check whether check is a value of any of the a[j] (that is a[0] to a[10])? A good and simple method?
Try this:
a.indexOf(check) > -1
Related
This question already has answers here:
What's the difference between ++i and i++ in JavaScript [duplicate]
(6 answers)
Closed 1 year ago.
I want to increase object value just like loop i++ , but in object didnt worked ,
how to increase this value ? any methods?
const object = {
price:30
}
console.log(object.price++);
using ++ like that is the post-increment operator meaning object.price++ returns object.price first then increments. You want the pre-increment operator ++object.price.
const object = {
price:30
}
console.log(++object.price);
This question already has answers here:
Why do Array.prototype.slice.call(nodeList) for DOM elements?
(2 answers)
Explanation of [].slice.call in javascript?
(9 answers)
Closed 2 years ago.
In ES5 if have a NodeList and want to loop through it must first convert it to Array with slice and call. I can't understand correctly how this statement works. I need explanation.
let nodeList = document.querySelectorAll('div');
let nToArr = Array.prototype.slice.call(nodeList);
// Then Loop Through it ....
This question already has answers here:
How to determine equality for two JavaScript objects?
(82 answers)
How do I check if an array includes a value in JavaScript?
(60 answers)
Closed 3 years ago.
IndexOf cannot find my object. Here is the JsFiddle
let a = [{}]
console.log(a.indexOf({}))
This question already has answers here:
How do I check if an array includes a value in JavaScript?
(60 answers)
Check if an element is present in an array [duplicate]
(9 answers)
Closed 4 years ago.
I recently starting learning JS so a beginner level answer would be great! Thanks.
function contains(arr, item) {
// check to see if item is inside of arr
// return true if it is, otherwise return false
}
What about something like this?
const arr = [1,2,3];
const el = 2;
console.log(arr.includes(el)) // true
This question already has answers here:
What is the difference between these arrays?
(5 answers)
Closed 9 years ago.
In JavaScript, what is the difference between
var stack = {};
and
var stack = [];
The first one is an empty object and the second is an empty array.