Javascript 如何使用jquery检查next()的结尾?
我对编程非常陌生,目前正在研究照片滑块的概念,当用户单击下一个箭头时,图像源将从我的li标记列表更改为下一个图像源。但是,我已经到了列表的末尾,如果当前图像源相同并且没有更改,我希望使用相同的图像源。我觉得我真的很接近!谢谢 我的HTML:Javascript 如何使用jquery检查next()的结尾?,javascript,jquery,Javascript,Jquery,我对编程非常陌生,目前正在研究照片滑块的概念,当用户单击下一个箭头时,图像源将从我的li标记列表更改为下一个图像源。但是,我已经到了列表的末尾,如果当前图像源相同并且没有更改,我希望使用相同的图像源。我觉得我真的很接近!谢谢 我的HTML: <div id="wrapper"> <div class="left-arrow"> <i class="arrow left"></i> </div>
<div id="wrapper">
<div class="left-arrow">
<i class="arrow left"></i>
</div>
<div class="image-holder"></div>
<div class="right-arrow">
<i class="arrow right"></i>
</div>
</div>
<ul class="images">
<li class="active"><img src="images/htmllogolg.png" alt="html" class="firstImg"></li>
<li><img src="images/csslogolg.png" alt="css"></li>
<li><img src="images/jslogolg.png" alt="js" class="lastImg"></li>
</ul>
<div id="wrapper">
<div class="left-arrow">
<i class="arrow left"></i>
</div>
<div class="image-holder"></div>
<div class="right-arrow">
<i class="arrow right"></i>
</div>
</div>
我的JavaScript/JQuery:
$(document).ready(function() {
// global variables
var $firstImg = $('.firstImg').attr('src');
var $lastImg = $('.lastImg').attr('src');
// get image src of the li with the class "active"
var $imageSrc = $('li.active>img').attr('src');
// append the image src of active into the div with class "image-holder"
$('.image-holder').append("<img src='" + $imageSrc + "'" + " class='placeImg'>");
// change src of image when user clicks the right arrow
$('.right').on('click', function() {
if ($('li.active').next().length > 3)) {
var $next = $('li.active').next();
var $nextSrc = $next.children('img').attr('src');
$('.placeImg').removeAttr('src');
$('.placeImg').attr('src', $nextSrc);
if ($('li').hasClass('active')) {
$('li').removeClass('active');
}
$next.addClass('active');
} else {
$('.placeImg').attr('src', $lastImg);
}
});
// change src of image when user clicks the left arrow
$('.left').on('click', function() {
var $prev = $('li.active').prev();
var $prevSrc = $prev.children('img').attr('src');
$('.placeImg').removeAttr('src');
$('.placeImg').attr('src', $prevSrc);
if ($('li').hasClass('active')) {
$('li').removeClass('active');
}
$prev.addClass('active');
});
});
$(文档).ready(函数(){
//全局变量
var$firstImg=$('.firstImg').attr('src');
var$lastImg=$('.lastImg').attr('src');
//获取类为“active”的li的图像src
var$imageSrc=$('li.active>img').attr('src');
//使用类“image holder”将active的image src追加到div中
$('.image holder')。追加(“”);
//当用户单击右箭头时更改图像的src
$('.right')。在('click',function()上{
如果($('li.active').next().length>3)){
var$next=$('li.active').next();
var$nextSrc=$next.children('img').attr('src');
$('.placeImg').removeAttr('src');
$('.placeImg').attr('src',$nextSrc);
if($('li').hasClass('active')){
$('li').removeClass('active');
}
$next.addClass('active');
}否则{
$('.placeImg').attr('src',$lastImg);
}
});
//当用户单击左箭头时更改图像的src
$('.left')。在('click',function()上{
var$prev=$('li.active').prev();
var$prevSrc=$prev.children('img').attr('src');
$('.placeImg').removeAttr('src');
$('.placeImg').attr('src',$prevSrc);
if($('li').hasClass('active')){
$('li').removeClass('active');
}
$prev.addClass(“活动”);
});
});
我自己想出来的!这是新代码
我的HTML:
<div id="wrapper">
<div class="left-arrow">
<i class="arrow left"></i>
</div>
<div class="image-holder"></div>
<div class="right-arrow">
<i class="arrow right"></i>
</div>
</div>
<ul class="images">
<li class="active"><img src="images/htmllogolg.png" alt="html" class="firstImg"></li>
<li><img src="images/csslogolg.png" alt="css"></li>
<li><img src="images/jslogolg.png" alt="js" class="lastImg"></li>
</ul>
<div id="wrapper">
<div class="left-arrow">
<i class="arrow left"></i>
</div>
<div class="image-holder"></div>
<div class="right-arrow">
<i class="arrow right"></i>
</div>
</div>
我的JavaScript:
$(document).ready(function() {
// global variables
var $firstImg = $('.firstImg').attr('src');
var $lastImg = $('.lastImg').attr('src');
// get image src of the li with the class "active"
var $imageSrc = $('li.active>img').attr('src');
// append the image src of active into the div with class "image-holder"
$('.image-holder').append("<img src='" + $imageSrc + "'" + " class='placeImg'>");
// change src of image when user clicks the right arrow
$('.right').on('click', function() {
var $next = $('li.active').next();
var $nextSrc = $next.children('img').attr('src');
if ($('.placeImg').attr('src') == $lastImg) {
$('.placeImg').attr('src', $lastImg);
} else {
$('.placeImg').removeAttr('src');
$('.placeImg').attr('src', $nextSrc);
if ($('li').hasClass('active')) {
$('li').removeClass('active');
}
$next.addClass('active');
}
});
// change src of image when user clicks the left arrow
$('.left').on('click', function() {
var $prev = $('li.active').prev();
var $prevSrc = $prev.children('img').attr('src');
if ($('.placeImg').attr('src') == $firstImg) {
$('.placeImg').attr('src', $firstImg);
} else {
$('.placeImg').removeAttr('src');
$('.placeImg').attr('src', $prevSrc);
if ($('li').hasClass('active')) {
$('li').removeClass('active');
}
$prev.addClass('active');
}
});
});
$(文档).ready(函数(){
//全局变量
var$firstImg=$('.firstImg').attr('src');
var$lastImg=$('.lastImg').attr('src');
//获取类为“active”的li的图像src
var$imageSrc=$('li.active>img').attr('src');
//使用类“image holder”将active的image src追加到div中
$('.image holder')。追加(“”);
//当用户单击右箭头时更改图像的src
$('.right')。在('click',function()上{
var$next=$('li.active').next();
var$nextSrc=$next.children('img').attr('src');
if($('.placeImg').attr('src')==$lastImg){
$('.placeImg').attr('src',$lastImg);
}否则{
$('.placeImg').removeAttr('src');
$('.placeImg').attr('src',$nextSrc);
if($('li').hasClass('active')){
$('li').removeClass('active');
}
$next.addClass('active');
}
});
//当用户单击左箭头时更改图像的src
$('.left')。在('click',function()上{
var$prev=$('li.active').prev();
var$prevSrc=$prev.children('img').attr('src');
if($('.placeImg').attr('src')==$firstImg){
$('.placeImg').attr('src',$firstImg);
}否则{
$('.placeImg').removeAttr('src');
$('.placeImg').attr('src',$prevSrc);
if($('li').hasClass('active')){
$('li').removeClass('active');
}
$prev.addClass(“活动”);
}
});
});