无法使用 setInterval 迭代整个字母表

Question

我希望代码每秒迭代每个字母，但它在一秒钟内迭代了整个字母表。

let alphabet = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z'];

setInterval(function() {
  for (let i = 0; i < alphabet.length; i++) {
    console.log(alphabet[i]);
  }
}, 1000);

Answer 1

如果你想在一秒后一个接一个地获取元素，那么你可以使用setTimeout而不是setInterval

setTimeout vs setInterval

let alphabet = [
  "a",
  "b",
  "c",
  "d",
  "e",
  "f",
  "g",
  "h",
  "i",
  "j",
  "k",
  "l",
  "m",
  "n",
  "o",
  "p",
  "q",
  "r",
  "s",
  "t",
  "u",
  "v",
  "w",
  "x",
  "y",
  "z",
];

for (let i = 0; i < alphabet.length; i++) {
  setTimeout(function () {
    console.log(alphabet[i]);
  }, i * 1000);
}

Answer 2

不用啊循环简单的区间就够了。如果迭代到达数组末尾，使用 clearInterval 停止迭代

const alphabet = ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h', 'i', 'j', 'k', 'l', 'm', 'n', 'o', 'p', 'q', 'r', 's', 't', 'u', 'v', 'w', 'x', 'y', 'z']


function run() {
  let i = 0;
  let interval = setInterval(() => {
    if (i === alphabet.length) {
      clearInterval(interval);
      return
    }
    console.log(alphabet[i])
    i++
  }, 1000)
}

run()

Answer 3

您不需要在 setInterval 中包含 for 循环。相反，您只需要声明一个 index 并在 setInterval 中更新它，一旦索引超出数组范围，您需要清除 timer.

let alphabet = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'] 
let index= 0;
const timer = setInterval(function () {
  index< alphabet.length
    ? console.log(alphabet[index++])
    : clearInterval(timer);
}, 1000);

Answer 4

发生这种情况是因为您遍历了整个数组，为避免这种情况，您需要为迭代添加索引 +1。

let alphabet = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'];

let i = 0;
let intervalID = setInterval(function (){
    
    console.log(alphabet[i]);
    
    i++;
    
    i < alphabet.length ? null : clearInterval(intervalID);
}, 1000);

Answer 5

这里只要setInterval就够了。无需添加循环。

let alphabet = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'];
let counter = 0;
let interval = setInterval( () => {
    console.log( alphabet[ counter++ ] );
    if( counter === alphabet.length ){
        clearInterval( interval );
    }
}, 1000 );

Answer 6

这个怎么样？从关闭开始清除间隔。

const alphabet = ['a','b','c','d','e','f','g','h','i','j','k','l','m','n','o','p','q','r','s','t','u','v','w','x','y','z'] 

let i = 0

const timerId = setInterval(function (){
    if(i === alphabet.length){
        clearInterval(timerId);
        console.log('Clear interval')
    }else{
        console.log(alphabet[i++]);
    }
}, 1000);

无法使用 setInterval 迭代整个字母表

Can't iterate whole alphabet using setInterval

javascript

asynchronous

setinterval