2016-11-28 125 views
0

是指w3schools的幻灯片放映代码。我试图自动幻灯片的图像,当我们点击点应该工作。但我无法使其自动这里是W3Schools的链接如何使现有幻灯片的自动幻灯片

http://www.w3schools.com/howto/tryit.asp?filename=tryhow_js_slideshow

var slideIndex = 1; 
 
showSlides(slideIndex); 
 

 
function plusSlides(n) { 
 
    showSlides(slideIndex += n); 
 
} 
 

 
function currentSlide(n) { 
 
    showSlides(slideIndex = n); 
 
} 
 

 
function showSlides(n) { 
 
    var i; 
 
    var slides = document.getElementsByClassName("mySlides"); 
 
    var dots = document.getElementsByClassName("dot"); 
 
    if (n > slides.length) {slideIndex = 1}  
 
    if (n < 1) {slideIndex = slides.length} 
 
    for (i = 0; i < slides.length; i++) { 
 
     slides[i].style.display = "none"; 
 
    } 
 
    for (i = 0; i < dots.length; i++) { 
 
     dots[i].className = dots[i].className.replace(" active", ""); 
 
    } 
 
    slides[slideIndex-1].style.display = "block"; 
 
    dots[slideIndex-1].className += " active"; 
 
}
* {box-sizing:border-box} 
 
body {font-family: Verdana,sans-serif;margin:0} 
 
.mySlides {display:none} 
 

 
/* Slideshow container */ 
 
.slideshow-container { 
 
    max-width: 1000px; 
 
    position: relative; 
 
    margin: auto; 
 
} 
 

 
/* Next & previous buttons */ 
 
.prev, .next { 
 
    cursor: pointer; 
 
    position: absolute; 
 
    top: 50%; 
 
    width: auto; 
 
    padding: 16px; 
 
    margin-top: -22px; 
 
    color: white; 
 
    font-weight: bold; 
 
    font-size: 18px; 
 
    transition: 0.6s ease; 
 
    border-radius: 0 3px 3px 0; 
 
} 
 

 
/* Position the "next button" to the right */ 
 
.next { 
 
    right: 0; 
 
    border-radius: 3px 0 0 3px; 
 
} 
 

 
/* On hover, add a black background color with a little bit see-through */ 
 
.prev:hover, .next:hover { 
 
    background-color: rgba(0,0,0,0.8); 
 
} 
 

 
/* Caption text */ 
 
.text { 
 
    color: #f2f2f2; 
 
    font-size: 15px; 
 
    padding: 8px 12px; 
 
    position: absolute; 
 
    bottom: 8px; 
 
    width: 100%; 
 
    text-align: center; 
 
} 
 

 
/* Number text (1/3 etc) */ 
 
.numbertext { 
 
    color: #f2f2f2; 
 
    font-size: 12px; 
 
    padding: 8px 12px; 
 
    position: absolute; 
 
    top: 0; 
 
} 
 

 
/* The dots/bullets/indicators */ 
 
.dot { 
 
    cursor:pointer; 
 
    height: 13px; 
 
    width: 13px; 
 
    margin: 0 2px; 
 
    background-color: #bbb; 
 
    border-radius: 50%; 
 
    display: inline-block; 
 
    transition: background-color 0.6s ease; 
 
} 
 

 
.active, .dot:hover { 
 
    background-color: #717171; 
 
} 
 

 
/* Fading animation */ 
 
.fade { 
 
    -webkit-animation-name: fade; 
 
    -webkit-animation-duration: 1.5s; 
 
    animation-name: fade; 
 
    animation-duration: 1.5s; 
 
} 
 

 
@-webkit-keyframes fade { 
 
    from {opacity: .4} 
 
    to {opacity: 1} 
 
} 
 

 
@keyframes fade { 
 
    from {opacity: .4} 
 
    to {opacity: 1} 
 
} 
 

 
/* On smaller screens, decrease text size */ 
 
@media only screen and (max-width: 300px) { 
 
    .prev, .next,.text {font-size: 11px} 
 
} 
 
</style> 
 
<body> 
 

 
<div class="slideshow-container">
<meta name="viewport" content="width=device-width, initial-scale=1"> 
 

 
<div class="mySlides fade"> 
 
    <div class="numbertext">1/3</div> 
 
    <img src="http://www.w3schools.com/howto/img_nature_wide.jpg" style="width:100%"> 
 
    <div class="text">Caption Text</div> 
 
</div> 
 

 
<div class="mySlides fade"> 
 
    <div class="numbertext">2/3</div> 
 
    <img src="http://www.w3schools.com/howto/img_fjords_wide.jpg" style="width:100%"> 
 
    <div class="text">Caption Two</div> 
 
</div> 
 

 
<div class="mySlides fade"> 
 
    <div class="numbertext">3/3</div> 
 
    <img src="http://www.w3schools.com/howto/img_mountains_wide.jpg" style="width:100%"> 
 
    <div class="text">Caption Three</div> 
 
</div> 
 

 
<a class="prev" onclick="plusSlides(-1)">❮</a> 
 
<a class="next" onclick="plusSlides(1)">❯</a> 
 

 
</div> 
 
<br> 
 

 
<div style="text-align:center"> 
 
    <span class="dot" onclick="currentSlide(1)"></span> 
 
    <span class="dot" onclick="currentSlide(2)"></span> 
 
    <span class="dot" onclick="currentSlide(3)"></span> 
 
</div>

+1

欢迎来到SO。请访问[帮助],看看有什么和如何问。建议:在此处发布EFFORT和CODE并提出具体问题 – mplungjan

+0

好的感谢您的信息 –

回答

0

你只需要一个的setInterval:

var slideIndex = 1; 
 

 
window.onload=function() { 
 
    showSlides(1); 
 
    setInterval(function() { plusSlides(1)},3000) 
 
} 
 

 
function plusSlides(n) { 
 
    showSlides(slideIndex += n); 
 
} 
 

 
function currentSlide(n) { 
 
    showSlides(slideIndex = n); 
 
} 
 

 
function showSlides(n) { 
 
    var i; 
 
    var slides = document.getElementsByClassName("mySlides"); 
 
    var dots = document.getElementsByClassName("dot"); 
 
    if (n > slides.length) {slideIndex = 1}  
 
    if (n < 1) {slideIndex = slides.length} 
 
    for (i = 0; i < slides.length; i++) { 
 
     slides[i].style.display = "none"; 
 
    } 
 
    for (i = 0; i < dots.length; i++) { 
 
     dots[i].className = dots[i].className.replace(" active", ""); 
 
    } 
 
    slides[slideIndex-1].style.display = "block"; 
 
    dots[slideIndex-1].className += " active"; 
 
}
* {box-sizing:border-box} 
 
body {font-family: Verdana,sans-serif;margin:0} 
 
.mySlides {display:none} 
 

 
/* Slideshow container */ 
 
.slideshow-container { 
 
    max-width: 1000px; 
 
    position: relative; 
 
    margin: auto; 
 
} 
 

 
/* Next & previous buttons */ 
 
.prev, .next { 
 
    cursor: pointer; 
 
    position: absolute; 
 
    top: 50%; 
 
    width: auto; 
 
    padding: 16px; 
 
    margin-top: -22px; 
 
    color: white; 
 
    font-weight: bold; 
 
    font-size: 18px; 
 
    transition: 0.6s ease; 
 
    border-radius: 0 3px 3px 0; 
 
} 
 

 
/* Position the "next button" to the right */ 
 
.next { 
 
    right: 0; 
 
    border-radius: 3px 0 0 3px; 
 
} 
 

 
/* On hover, add a black background color with a little bit see-through */ 
 
.prev:hover, .next:hover { 
 
    background-color: rgba(0,0,0,0.8); 
 
} 
 

 
/* Caption text */ 
 
.text { 
 
    color: #f2f2f2; 
 
    font-size: 15px; 
 
    padding: 8px 12px; 
 
    position: absolute; 
 
    bottom: 8px; 
 
    width: 100%; 
 
    text-align: center; 
 
} 
 

 
/* Number text (1/3 etc) */ 
 
.numbertext { 
 
    color: #f2f2f2; 
 
    font-size: 12px; 
 
    padding: 8px 12px; 
 
    position: absolute; 
 
    top: 0; 
 
} 
 

 
/* The dots/bullets/indicators */ 
 
.dot { 
 
    cursor:pointer; 
 
    height: 13px; 
 
    width: 13px; 
 
    margin: 0 2px; 
 
    background-color: #bbb; 
 
    border-radius: 50%; 
 
    display: inline-block; 
 
    transition: background-color 0.6s ease; 
 
} 
 

 
.active, .dot:hover { 
 
    background-color: #717171; 
 
} 
 

 
/* Fading animation */ 
 
.fade { 
 
    -webkit-animation-name: fade; 
 
    -webkit-animation-duration: 1.5s; 
 
    animation-name: fade; 
 
    animation-duration: 1.5s; 
 
} 
 

 
@-webkit-keyframes fade { 
 
    from {opacity: .4} 
 
    to {opacity: 1} 
 
} 
 

 
@keyframes fade { 
 
    from {opacity: .4} 
 
    to {opacity: 1} 
 
} 
 

 
/* On smaller screens, decrease text size */ 
 
@media only screen and (max-width: 300px) { 
 
    .prev, .next,.text {font-size: 11px} 
 
} 
 
</style> 
 
<body> 
 

 
<div class="slideshow-container">
<meta name="viewport" content="width=device-width, initial-scale=1"> 
 

 
<div class="mySlides fade"> 
 
    <div class="numbertext">1/3</div> 
 
    <img src="http://www.w3schools.com/howto/img_nature_wide.jpg" style="width:100%"> 
 
    <div class="text">Caption Text</div> 
 
</div> 
 

 
<div class="mySlides fade"> 
 
    <div class="numbertext">2/3</div> 
 
    <img src="http://www.w3schools.com/howto/img_fjords_wide.jpg" style="width:100%"> 
 
    <div class="text">Caption Two</div> 
 
</div> 
 

 
<div class="mySlides fade"> 
 
    <div class="numbertext">3/3</div> 
 
    <img src="http://www.w3schools.com/howto/img_mountains_wide.jpg" style="width:100%"> 
 
    <div class="text">Caption Three</div> 
 
</div> 
 

 
<a class="prev" onclick="plusSlides(-1)">❮</a> 
 
<a class="next" onclick="plusSlides(1)">❯</a> 
 

 
</div> 
 
<br> 
 

 
<div style="text-align:center"> 
 
    <span class="dot" onclick="currentSlide(1)"></span> 
 
    <span class="dot" onclick="currentSlide(2)"></span> 
 
    <span class="dot" onclick="currentSlide(3)"></span> 
 
</div>