从数组中选择随机索引总是会返回相同的索引吗？

Question

var letters = ["a", "b", "c", "d", "e", "f", "g", "h"]



var letter  = letter[Math.round(Math.random()*(quotes.length))]

Every time it just returns the last letter, g, not a random one from the array.

What am I doing wrong?

Answer 1

(quotes.length)

What is quotes ? You want letters .

You're doing var letter = letter , but letter hasn't been defined yet. Also, when choosing a random element from an array, use Math.floor instead of Math.round :

 const letters = ["a", "b", "c", "d", "e", "f", "g", "h"]; const letter = letters[Math.floor(Math.random()*letters.length)]; console.log(letter); 

Answer 2

Probably need to fix a few typos in your code:

var letters = ["a", "b", "c", "d", "e", "f", "g", "h"]
var letter  = letters[Math.round(Math.random()*(letters.length))]

Also, you may not want to use Math.round since it can cause an out-of-bound array access error. You should try Math.floor instead.

Answer 3

修正错别字，您应该会没事的

var letter = letters[Math.round(Math.random()*(letters.length))]