Javascript 将变量名与for循环中的迭代器索引连接起来
我试图在javascript中创建一组按钮,使滑块根据我单击的按钮交换图像 我想出了这个丑陋的冗余代码:Javascript 将变量名与for循环中的迭代器索引连接起来,javascript,Javascript,我试图在javascript中创建一组按钮,使滑块根据我单击的按钮交换图像 我想出了这个丑陋的冗余代码: var changer1 = document.getElementById("changer1"); var changer2 = document.getElementById("changer2"); var changer3 = document.getElementById("changer3"); var r = document.getElementsByClassName(
var changer1 = document.getElementById("changer1");
var changer2 = document.getElementById("changer2");
var changer3 = document.getElementById("changer3");
var r = document.getElementsByClassName('carousel-item');
changer1.addEventListener('click', function() {
for (let i = 0; i < r.length; i++) {
r[i].classList.remove('active')
}
r[0].classList.add('active')
});
changer2.addEventListener('click', function() {
for (let i = 0; i < r.length; i++) {
r[i].classList.remove('active')
}
r[1].classList.add('active')
});
changer3.addEventListener('click', function() {
for (let i = 0; i < r.length; i++) {
r[i].classList.remove('active')
}
r[2].classList.add('active')
});
var changer1=document.getElementById(“changer1”);
var changer2=document.getElementById(“changer2”);
var changer3=document.getElementById(“changer3”);
var r=document.getElementsByClassName('carousel-item');
changer1.addEventListener('click',function(){
for(设i=0;i
这是可行的,但我知道冗余代码可以优化,所以我尝试了以下方法:
var changersArray = document.getElementsByClassName('changers');
for (let i = 0; i < 3; i++) {
changer[i].addEventListener('click', function() {
for (let i = 0; i < r.length; i++) {
r[i].classList.remove('active')
}
r[0].classList.add('active')
});
}
var changersArray=document.getElementsByClassName('changers');
对于(设i=0;i<3;i++){
转换器[i]。addEventListener('click',函数(){
for(设i=0;i
这是HTML:
<section class="container-fluid sectionFive">
<div class="row title_image">
<div class="col-sm-12">
<h1 class="wow flipInY delay-1s slow">Testimonials</h1>
</div>
</div>
<div class="row">
<div class="col-sm-2"></div>
<div class="col-sm-8 fetchDiv">
<div id="carouselExampleControls" class="carousel slide wow
fadeIn" data-ride="carousel">
<div class="carousel-inner">
<div class="carousel-item active">
<img class="mt-2 rounded-circle people" src="images/person_3.jpg" alt="">
<p class="frase"></p>
<p class="author"></p>
</div>
<div class="carousel-item">
<img class="mt-2 rounded-circle people" src="images/person_2.jpg" alt="">
<p class="frase"></p>
<p class="author"></p>
</div>
<div class="carousel-item">
<img class="mt-2 rounded-circle people" src="images/person_1.jpg" alt="">
<p class="frase"></p>
<p class="author"></p>
</div>
</div>
<a class="carousel-control-prev" href="#carouselExampleControls" role="button" data-slide="prev">
<span class="carousel-control-prev-icon" aria-hidden="true"></span>
<span class="sr-only">Previous</span>
</a>
<a class="carousel-control-next" href="#carouselExampleControls" role="button" data-slide="next">
<span class="carousel-control-next-icon" aria-hidden="true"></span>
<span class="sr-only">Next</span>
</a>
</div>
</div>
<div class="col-sm-2">
</div>
</div>
<div class="row changersRow">
<button class="changers" id="changer1">1</button><button class="changers" id="changer2">2</button><button class="changers" id="changer3">3</button>
</div>
</section>
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我试图通过在循环中写入changer[I]来动态创建changer1、changer2和changer3,但没有成功
拜托,你能帮我弄清楚为什么它不起作用,我怎样才能让它起作用
谢谢。头两项改进来自我的头脑:
for (let i = 0; i < 3; i++) {
changer[i].addEventListener('click', function() {
for (let j = 0; j < r.length; j++) {
r[j].classList.remove('active')
}
r[i].classList.add('active')
});
}
for(设i=0;i<3;i++){
转换器[i]。addEventListener('click',函数(){
对于(设j=0;j
请注意,内部的
i
已被替换,而r[0]
已更改为使用实际索引也请共享HTML。为什么在内部for循环和外部for循环中有相同的i
?我共享了HTML,请看一看,是的,我没有看到我对外部和内部循环使用了相同的索引。