Search results
Jun 10, 2010 · As long as your JavaScript implementation is compliant with the previous edition of the ECMAScript specification (which rules out, for example, versions of Internet Explorer before 9), then you can use the Array#forEach iterator method instead of a loop. In that case, you pass a function to be called on each item in the array:
Jan 17, 2013 · So you can iterate over the Object and have key and value for each of the object and get something like this. const key = obj[0]; const value = obj[1]; // do whatever you want with those values. or like this. console.log(`${key} ${value}`); // "a 5", "b 7", "c 9".
Aug 27, 2010 · Since ES7 theres a better way to await a loop: // Returns a Promise that resolves after "ms" Milliseconds const timer = ms => new Promise(res => setTimeout(res, ms)) async function load { // We need to wrap the loop into an async function for this to work for (var i = 0; i < 3; i++) { console.log(i); await timer(3000); // then the created Promise can be awaited } } load();
Feb 17, 2012 · Loop using forEach. forEach is a function which is located on Array.prototype which takes a callback function as an argument. It then executes this callback function for every element in the array. In contrast to the map() function, the forEach function returns nothing (undefined).
Oct 27, 2023 · Here's a simple example of using the default iterator (which is also the one you get from entries): const map = new Map(); map.set(1, "one"); // Could also include these when calling. map.set(2, "two"); // the constructor but I wanted to. map.set(3, "three"); // avoid any confusion.
Oct 1, 2008 · Looping from length to 0 would be more efficient than looping from 0 to length. And using a reversed while loop is more efficient than a foor loop as you said. I don't have the link to the page with comparison results anymore but I remember that the difference varied on different browsers. For some browser the reversed while loop was twice as fast.
May 6, 2013 · Upon the spec from MDN, Set has a values method: The values () method returns a new Iterator object that contains the values for each element in the Set object in insertion order. So, for iterate through the values, I would do: var s = new Set(['a1', 'a2']) for (var it = s.values(), val= null; val=it.next().value; ) {. console.log(val); }
Mar 2, 2010 · In JavaScript, if you're looking for A or B, but not both, you'll need to do something similar to:
ECMAScript 5: No, it's not possible with objects. You should either iterate with for..in, or Object.keys, like this
Break for loop from inside of switch case in Javascript. 6. Uses of colon in javascript. 6.
