Question

我想知道是否有人可以帮助我并解释为什么，当我拆分innerText时，它有时返回undefined，是否有人可以向我指出正确的解决方法

var elems = document.getElementsByClassName("hud-leaderboard-party"),
  counter = elems.length,
  arrayLength = 0,
  maxLengthArray = 0;

// LEADERBOARD NAMES
window.leaderboardNames = function() {
  var Elem;
  if (counter <= 0)
    counter = elems.length;
  Elem = elems[counter - 1];
  document.getElementsByClassName("hud-intro-name")[0].value = Elem.innerText.split("—")[0].split(",")[arrayLength];
  maxLengthArray = Elem.innerText.split("—")[0].split(",").length;
  if (maxLengthArray == arrayLength) {
    arrayLength = 0;
    counter--;
  } else {
    arrayLength++;
  }
}

<div class="hud-intro-leaderboard">
  <div class="hud-intro-leaderboard-parties">
    <div class="hud-leaderboard-party">Player name here 1, Player name here 2, Player name here 3, Player name here 4 — <strong>998</strong></div>
    <div class="hud-leaderboard-party">Player name here 5, Player name here 6, Player name here 7 — <strong>707</strong></div>
    <div class="hud-leaderboard-party">Player name here 8, Player name here 9, Player name here 10 — <strong>610</strong></div>
    <div class="hud-leaderboard-party">Player name here 11, Player name here 12 — <strong>448</strong></div>
    <div class="hud-leaderboard-party">Player name here 13, Player name here 14, Player name here 15, Player name here 16 — <strong>409</strong></div>
  </div>
</div>

<br><br>
<button class="btn btn-green" style="width: 90%;" onclick="leaderboardNames();">LEADERBOARD NAMES</button>
<br><br>
<input type="text" class="hud-intro-name" style="width: 90%;" maxlength="29" placeholder="Your nickname">

Answer 1

如果-后面的值不具有，则会发生未定义的情况，

所以在声明中

Elem.innerText.split("—")[0].split(",")[arrayLength];

您需要先检查

Elem.innerText.split("—")[0].split(",")

并安全地从中提取。

Answer 2

在您的arrayLength检查中发出问题，需要为+1

let elems = document.getElementsByClassName("hud-leaderboard-party"),
  counter = elems.length,
  arrayLength = 0,
  maxLengthArray = 0;

// LEADERBOARD NAMES
window.leaderboardNames = function() {
  let elem;
  
  if (counter <= 0) {
    console.log(counter);
    counter = elems.length;
    }
  elem = elems[counter - 1];
  let elemNames = elem.innerText.split("—")[0].split(',');
  
  document.querySelector(".hud-intro-name").value = elemNames[arrayLength];
  
  maxLengthArray = elem.innerText.split("—")[0].split(",").length;
  if (maxLengthArray == arrayLength+1) {
    arrayLength = 0;
    counter--;
  } else {
    arrayLength++;
  }
}

<div class="hud-intro-leaderboard">
  <div class="hud-intro-leaderboard-parties">
    <div class="hud-leaderboard-party">⋘TC⋙ ƘƠƦƘƲƧƲȤ, ƬƇ☢☠ⓀⓊⓇⓉ☠☢, ⋘TC⋙ ƘƠƦƘƲƧƲȤ, ƬƇ☢☠ⓀⓊⓇⓉ☠☢ — <strong>998</strong></div>
    <div class="hud-leaderboard-party">Sweet Heart TW, High Score GO!, High Score GO! — <strong>707</strong></div>
    <div class="hud-leaderboard-party">K¥LË, K¥LË3, This has been removed, This has been removed — <strong>610</strong></div>
    <div class="hud-leaderboard-party">Exxotic, ภคŦғเค :P... (MSR), Hauzz✔️ — <strong>448</strong></div>
    <div class="hud-leaderboard-party">Brightstar, Yaslin, Yaslin, Yaslin — <strong>409</strong></div>
  </div>
</div>

<br><br>
<button class="btn btn-green" style="width: 90%;" onclick="leaderboardNames();">LEADERBOARD NAMES</button>
<br><br>
<input type="text" class="hud-intro-name" style="width: 90%;" maxlength="29" placeholder="Your nickname">

JavaScript拆分返回未定义

2 个答案: