Question

有人可以帮忙吗？我似乎无法弄清楚为什么它不起作用。谢谢。

<p class="largetext">GGS</p>

        <script type="text/javascript">

            window.addEventListener("scroll", function(){
                var textY = document.getElementsByClassName("largetext")
                for(var i = 0; i < textY.length; i++){if (2 > 1)


                    {textY[i].innerHTML = "passed"; }                                                  
                    else {
                    textY[i].innerHTML = "failed";}}) 
            </script>

Answer 1

window.addEventListener("scroll", function(){应该用});而不是}关闭。

这是您的代码：

window.addEventListener("scroll", function(){
                var textY = document.getElementsByClassName("largetext");
                for(var i = 0; i < textY.length; i++){
                   if (2 > 1) {
                    textY[i].innerHTML = "passed";
                   } else {
                    textY[i].innerHTML = "failed";
                   }
                }
            });

.largetext {
  width: 100%;
  height: 100px;
}

<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>
<div class="largetext"></div>

Answer 2

问题出在您的代码中，您错过了函数的右花括号，这就是它引发错误的原因。

.largetext{min-height: 200vh}

<p class="largetext">GGS</p>

        <script type="text/javascript">

            window.addEventListener("scroll", function(){
                var textY = document.getElementsByClassName("largetext")
                for(var i = 0; i < textY.length; i++){
                if (2 > 1){
                textY[i].innerHTML = "passed";
                }                                                  
                    else {
                    textY[i].innerHTML = "failed";
                    }
               }
               
               }) 
            </script>

if语句的getElementsByClassName问题

2 个答案: