Picking a random array element from an array

Question

Possible Duplicate:
How can I return a random value from an array?
Getting random value from an array

If you have an array of:

days = ["Monday","Tuesday","Wednesday","Thursday","Friday","Saturday","Sunday"]

How would I randomly pick an element from this array?

Though the title of the linked duplicate is jQuery, it's actually pure JavaScript so fit here as well. — Shadow The GPT Wizard, Dec 08 '11 at 12:39
@Tomalak nice, the duplicate link still show the old title though.. hope it's just cache. — Shadow The GPT Wizard, Dec 08 '11 at 12:44
@ShadowWizard: I don't think the title gets updated in the comments, you'd have to edit it. — Felix Kling, Dec 08 '11 at 12:59
@Felix Hopefully it will get closed then the comment will be automatically removed.. — Shadow The GPT Wizard, Dec 08 '11 at 13:16

score 2 · Answer 1 · answered Dec 08 '11 at 12:38

2

var randomDay = days[Math.floor(Math.random()*days.length)]
document.write(randomDay);

answered Dec 08 '11 at 12:38

evilone

22,410
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score 1 · Answer 2 · answered Dec 08 '11 at 12:38

1

You could use

days[Math.floor(Math.random()*days.length)];

answered Dec 08 '11 at 12:38

Thomas Johan Eggum

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score 0 · Answer 3 · answered Dec 08 '11 at 12:46

If you wanted you could make this a generic function of all Arrays, i.e.

Array.prototype.getRandomElement = function () {
    return this[Math.floor(Math.random() * this.length)];
};

var days = ["Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday",
    randomDay = days.getRandomElement();

Picking a random array element from an array

3 Answers3