为什么background-size或background-repeat属性在我的图像滑块上不起作用？

Question

我正在JS中制作图像滑块，现在我只是在处理右箭头按钮，单击该按钮时，它会循环遍历img文件夹中的图像。但是，当我单击箭头转到下一张图像时，新图像会丢失我在CSS中为其设置的几个属性；背景大小和重复属性。我发现的解决方法是将它们重新添加到JS中。

rightArrow.addEventListener('click', function() {
    num++;
    img.style.background = 'url(img/fam-' + num + '.jpeg)';
    img.style.backgroundRepeat = 'no-repeat'; // Have to add this property back on even though its already in the CSS
    img.style.backgroundSize = 'cover'; // Have to add this property back on even though its already in the CSS
})

我不想这么做。为什么更改图像时这些属性停止工作？我也不能在这里发布我的完整代码，因为它太长了，而且小提琴链接也没有太大帮助，因为你看不到图片 https://jsfiddle.net/yat5ncmk/3/

const ham = document.querySelector('.nav-box');
const menu = document.querySelector('.menu');
const menuClose = document.querySelector('#menu-close');
const leftArrow = document.querySelector('#left');
const rightArrow = document.querySelector('#right');
const img = document.querySelector('.image-slider');
let num = 1;

ham.addEventListener('click', function() {
    ham.classList.add('ham-open');
    menu.style.marginLeft = '50px';
})

menuClose.addEventListener('click', function() {
    ham.classList.remove('ham-open');
    menu.style.marginLeft = '-700px';
})

leftArrow.addEventListener('click', function() {
	
})

rightArrow.addEventListener('click', function() {
    num++;
    img.style.background = 'url(img/fam-' + num + '.jpeg)';
    img.style.backgroundRepeat = 'no-repeat';
    img.style.backgroundSize = 'cover';
})


// window.sr = ScrollReveal();

// sr.reveal('.logo-wrap', {
// 	duration: 2000,
// 	origin: 'left',
// });

// sr.reveal('.w1', {
// 	duration: 2000,
// 	origin: 'bottom'
// });

// sr.reveal('.w2', {
// 	duration: 3000,
// 	origin: 'bottom'
// });

// sr.reveal('.w3', {
// 	duration: 4000,
// 	origin: 'bottom'
// });

// sr.reveal('.b1', {
// 	duration: 2000,
// 	origin: 'top',
// 	distance: '50px'
// });

// sr.reveal('.b2', {
// 	duration: 1500,
// 	origin: 'top',
// 	distance: '75px'
// });

// sr.reveal('.b3', {
// 	duration: 1000,
// 	origin: 'top',
// 	distance: '100px'
// });

// sr.reveal('#left', {
// 	duration: 1000,
// 	origin: 'top',
// 	distance: '50px'
// });

// sr.reveal('#right', {
// 	duration: 1000,
// 	origin: 'top',
// 	distance: '50px'
// });

const ham = document.querySelector('.nav-box');
const menu = document.querySelector('.menu');
const menuClose = document.querySelector('#menu-close');
const leftArrow = document.querySelector('#left');
const rightArrow = document.querySelector('#right');
const img = document.querySelector('.image-slider');
let num = 1;

ham.addEventListener('click', function() {
    ham.classList.add('ham-open');
    menu.style.marginLeft = '50px';
})

menuClose.addEventListener('click', function() {
    ham.classList.remove('ham-open');
    menu.style.marginLeft = '-700px';
})

leftArrow.addEventListener('click', function() {
	
})

rightArrow.addEventListener('click', function() {
    num++;
    img.style.background = 'url(img/fam-' + num + '.jpeg)';
    img.style.backgroundRepeat = 'no-repeat'; // Have to add this property back on even though its already in the CSS
    img.style.backgroundSize = 'cover'; // Have to add this property back on even though its already in the CSS
})


// window.sr = ScrollReveal();

// sr.reveal('.logo-wrap', {
// 	duration: 2000,
// 	origin: 'left',
// });

// sr.reveal('.w1', {
// 	duration: 2000,
// 	origin: 'bottom'
// });

// sr.reveal('.w2', {
// 	duration: 3000,
// 	origin: 'bottom'
// });

// sr.reveal('.w3', {
// 	duration: 4000,
// 	origin: 'bottom'
// });

// sr.reveal('.b1', {
// 	duration: 2000,
// 	origin: 'top',
// 	distance: '50px'
// });

// sr.reveal('.b2', {
// 	duration: 1500,
// 	origin: 'top',
// 	distance: '75px'
// });

// sr.reveal('.b3', {
// 	duration: 1000,
// 	origin: 'top',
// 	distance: '100px'
// });

// sr.reveal('#left', {
// 	duration: 1000,
// 	origin: 'top',
// 	distance: '50px'
// });

// sr.reveal('#right', {
// 	duration: 1000,
// 	origin: 'top',
// 	distance: '50px'
// });

html, body {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

.header {
    background: url(img/mex-9.jpg);
    width: 100%;
    height: 100vh;
    background-size: cover;
    background-attachment: fixed;
    background-position: center;
    display: flex;
}

.nav-wrap {
    flex-basis: 40%;
}

.nav-wrap i {
    color: white;
    font-size: 2rem;
    position: absolute;
    right: -33px;
    top: 0px;
    transition: all .1s ease;
}

.nav-wrap i:hover {
    cursor: pointer;
    transform: scale(1.15);
}

.nav-box {
    margin-left: 50px;
    margin-top: 100px;
    max-width: 70px;
    cursor: pointer;
    position: fixed;
    z-index: 10;
}

.b1, .b2, .b3 {
    width: 70px;
    height: 8.5px;
    border-radius: 5px;
    background-color: #fff;
    margin-bottom: 10px;
    transition: all .15s ease;
}

.b1 {
    background-color: #56ff47;
}

.b3 {
    background-color: #ff4c4c;
}

.ham-open .b1 {
    background-color: #56ff47;
    transform: translateY(100px);
    position: relative;
    z-index: 1;
}

.ham-open .b2 {
    transform: translateY(81.5px);
    width: 110px;
    position: relative;
    left: 60px;
    z-index: 0;
}

.ham-open .b3 {
    background-color: #ff4c4c;
    transform: translateY(63px);
    width: 140px;
    position: relative;
    left: 160px;
    z-index: 2;
}

.menu {
    display: flex;
    border-left: 8px solid #56ff47;
    flex-direction: column;
	background-color: #fff;
	margin-left: -700px;
	width: 292px;
	padding-top: 10px;
	padding-bottom: 10px;
	position: fixed;
	border-radius: 5px;
	top: 225px;
	transition: all .15s;
	z-index: 10;
}

.menu a {
	text-decoration: none;
	color: limegreen;
	font-family: 'Kumar One Outline';
	font-size: 2.3rem;
	text-align: center;
	margin-top: 12px;
	margin-bottom: 12px;
	transition: all .5s ease;
}

a:hover {
	color: #007001;
}

.info-wrap {
	flex-basis: 60%;
}

.info {
	font-family: 'Cedarville Cursive';
	color: white;
	font-weight: bold;
	font-size: 4.5rem;
	text-align: center;
	margin-top: 60px;
}

.logo-wrap {
	display: flex;
	justify-content: center;
	flex-direction: column;
}

.logo-wrap div {
	font-family: 'Staatliches';
	color: white;
	font-size: 13rem;
	font-weight: bold;
	letter-spacing: 10px;
	margin-bottom: -5rem;
	position: relative;
	margin-left: auto;
	margin-right: auto;

}




/*---------------ABOUT---------------*/




.about-section {
	background-color: #17a832;
	width: 100%;
	position: relative;
}

.about-section h1 {
	text-align: center;
	font-size: 4.5rem;
	margin-top: 0;
	margin-bottom: 30px;
	padding-top: 15px;
	color: white;
	font-family: 'Cedarville Cursive';
	font-weight: bold;
}

.about-line {
	width: 350px;
	height: 5px;
	background-color: #ddae1a;
	border-radius: 4px;
	position: absolute;
	top: 120px;
	left: 0;
	right: 0;
	bottom: 0;
	margin: 0 auto;
}

.about-wrap {
	display: flex;
	padding-bottom: 150px;
}

.about-info, .image-slider-wrap {
	flex-basis: 50%;
}

.about-info p {
	color: white;
	font-family: 'Josefin Sans';
	font-size: 2rem;
	margin-left: 100px;
	margin-bottom: 0;
	margin-top: 0;
}

.image-slider {
	width: 650px;
	height: 400px;
	background: url(img/fam-1.jpeg);
	background-position: center;
	background-size: cover;
	background-repeat: no-repeat;
	border-radius: 13px;
	margin-left: auto;
	margin-right: auto;
	position: relative;
}

.image-slider i {
	color: white;
	font-size: 5rem;
	position: absolute;
	top: 50%;
	margin-top: -40px;
	transition: all .1s ease;
	cursor: pointer;
}

#left {
	transform: rotate(-90deg);
	left: -30px;
	max-width: 50px;
}

#right {
	transform: rotate(90deg);
	right: -30px;
}

#left:hover {
	transform: rotate(-90deg) scale(1.3);
}

#right:hover {
	transform: rotate(90deg) scale(1.3);
}

.burrito, .taco, .guac, .nachos, .hot {
	position: absolute;
	transform: rotate(-45deg);
	bottom: -130px;
	right: 200px;
	width: 300px;
	height: 300px;
	z-index: 3;
	background-repeat: none;
}

.hot {
    right: 345px;
    width: 240px;
    height: 240px;
    z-index: 2;
    transform: rotate(0deg);
}

.burrito {
	bottom: -140px;
	right: 180px;
	z-index: 1;
}

.nachos {
	transform: rotate(0deg);
	right: 380px;
	width: 165px;
	height: 165px;
	bottom: -170px;
}

.taco {
	transform: rotate(0deg);
	width: 220px;
	height: 220px;
	bottom: -180px;
	right: 460px;
}

.guac {
	transform: rotate(0deg);
	right: 140px;
	bottom: -180px;
	width: 250px;
	height: 250px;
}

.food-wrap {
	position: relative;
	right: 20px;
}




/*---------------MENU---------------*/




.menu-section {
	background-color: #ddae1a;
	display: flex;
	width: 100%;
	top: -100px;
	position: relative;
	clip-path: polygon(0% 0%, 100% 3%, 100% 100%, 0% 100%);
	/*background-image: linear-gradient(4deg, #edb12f 92%, #17a832 92%, #17a832);*/
}

.menu-section h1 {
	font-size: 9.5rem;
	position: absolute;
	top: 30px;
	left: 230px;
	margin-top: -30px;
	padding-top: 15px;
	color: white;
	font-family: 'Cedarville Cursive';
	font-weight: bold;	
}

.menu-line {
	width: 450px;
	height: 5px;
	background-color: #17a832;
	border-radius: 4px;
	position: absolute;
	top: 220px;
	left: 225px;

}

.column-left, .column-right, .column-middle {
	flex-basis: 33.33%;
	margin-top: 230px;
	padding-bottom: 120px;
}

.column-left {
	display: flex;
	justify-content: flex-end;
}

.column-left #combo-platter:after {
	display: block;
	content: "beans and rice included";
	color: white;
	font-size: 1.5rem;
	font-family: 'Josefin Sans';
	margin-top: -25px;
}

.column-left h2:not(#combo-platter):after, .column-middle h2:after, .column-right h2:after {
	content: "";
	display: block;
	width: 100%;
	height: 2px;
	background-color: white;
	border-radius: 3px;
	margin-top: -25px;
}

.column-middle {
	display: flex;
	justify-content: center;
}

.column-right {
	display: flex;
	justify-content: flex-start;
}

.column {
	min-width: 420px;
	display: flex;
	flex-direction: column;
	position: relative;
	overflow: hidden;
}

.column h2 {
	display: inline-block;
	align-self: center;
	font-family: 'Cedarville Cursive';
	color: #17a832;
	font-size: 3rem;
}

.row {
	font-family: 'Josefin Sans';
	font-size: 1.5rem;
}

.row div {
	display: flex;
	justify-content: space-between;
}

.row div:after {
	display: inline-block;
	position: absolute;
	content: "";
	width: 100%;
	margin-top: 33px;
	border-top: 4px dotted black;
}

.row div p {
	background: #ddae1a;
	overflow: hidden;
	position: relative;
	z-index: 1;
	padding: 0 6px; 
}

.menu-h2 {
	text-align: center;
}

.design-left, .design-right {
	position: absolute;
}

.design-right {
	right: 0;
	transform: rotate(180deg);
}

.arrow-right {
    width: 0; 
    height: 0; 
    border-top: 30px solid transparent;
    border-bottom: 30px solid transparent; 
    border-left: 60px solid green;
 	position: relative;
 	top: -10px;
}

.arrow-left {
  width: 0; 
  height: 0; 
  border-top: 30px solid transparent;
  border-bottom: 30px solid transparent;  
  border-right:60px solid limegreen;
  position: relative;
  top: 20px; 
}

.arrow-top {
    width: 0; 
    height: 0; 
    border-top: 30px solid transparent;
    border-bottom: 30px solid transparent; 
    border-left: 60px solid #20a04b;
 	position: relative;
 	top: -100px;
 	left: 60px;
}

.top-middle {
	position: relative;
	top: -110px;
}

.bottom-middle .arrow-left {
	top: -40px;
}

.bottom-middle .move {
	top: -70px;
}

.bottom {
	position: relative;
	top: -48px;
}

.bottom .arrow-left {
	top: -40px;
}




/*---------------HOURS---------------*/




.hours-section {
	background-color: #17a832;
	margin-top: -155px;
	clip-path: polygon(0% 5%, 4.8% 0%, 95% 0%, 100% 4.8%, 100% 100%, 0% 100%);
	position: relative;
}

.hours-section h1 {
	text-align: center;
	font-size: 5rem;
	margin-top: 0;
	margin-bottom: 30px;
	padding-top: 15px;
	color: white;
	font-family: 'Cedarville Cursive';
	font-weight: bold;
}

.hours-line-left {
	width: 750px;
	height: 10px;
	border-radius: 4px;
	background-color: #ff4c4c;
	position: absolute;
	top: 10%;
	left: 50px;
}

.hours-line-right {
	width: 750px;
	height: 10px;
	border-radius: 4px;
	background-color: #56ff47;
	position: absolute;
	top: 10%;
	right: 50px;
}

.hours-wrap {
	display: flex;
	justify-content: center;
	padding-bottom: 100px;
}

.hours {
	display: flex;
	border: 7px solid green;
	padding: 25px;
}

.hours div div {
	background-color: white;
	color: black;
	margin-bottom: 20px;
	padding: 8px;
	font-size: 3rem;
	font-family: 'Josefin Sans';
	border-right: 10px solid #56ff47;
}

.hours div div:last-child {
	margin-bottom: 0;
}

.hours p {
	margin: 0;
	text-align: center;
}

.hours-open div {
	margin-left: 30px;
}

.hours .hours-open p {
	padding: 0 5px;
}

.design-wrap-left-side {
	position: absolute;
	left: 0;
	top: 29.8%;
}

.hex-left, .hex-right {
	-webkit-clip-path: polygon(47% 5%, 87% 24%, 87% 76%, 47% 95%, 10% 76%, 10% 24%);
	width: 165px;
	height: 165px;
	background-color: limegreen;
	top: 152px;
	left: -16.5px;
	position: absolute;
}

.hex-right {
	top: 152px;
	right: -16.5px;
}

.hex-inner {
	-webkit-clip-path: polygon(47% 5%, 87% 24%, 87% 76%, 47% 95%, 10% 76%, 10% 24%);
	width: 135px;
	height: 135px;
	background-color: #17a832;
	position: absolute;
	left: 0;
	right: 0;
	bottom: 0;
	top: 0;
	margin: auto; 
}

.hex-arrow-left, .hex-arrow-right {
    width: 0; 
    height: 0; 
    border-top: 35px solid transparent;
    border-bottom: 35px solid transparent; 
    border-left: 70px solid limegreen;
 	position: absolute;
 	top: 200px;
 	right: -150px;
}

.design-wrap-right-side {
	transform: rotate(180deg);
	position: absolute;
	right: 0;
	bottom: 19.4%;
}

.hours-wrap .design-wrap-left {
	transform: rotate(180deg);
	position: relative;
	top: -80px;
}

.hours-wrap .design-wrap-right {
	position: relative;
	top: 80px;
}

.design-wrap-left .arrow-top, 
.design-wrap-right .arrow-top, 
.design-wrap-left-side .arrow-top,
.design-wrap-right-side .arrow-top {
	width: 0; 
    height: 0; 
    border-top: 30px solid transparent;
    border-bottom: 30px solid transparent; 
    border-left: 60px solid limegreen;
 	position: relative;
 	top: -100px;
 	left: 60px;
}

.change-color {
    width: 0; 
    height: 0; 
    border-top: 30px solid transparent;
    border-bottom: 30px solid transparent; 
    border-left: 60px solid #6acc66;
 	position: absolute;
 	top: -10px;
}




/*---------------FOOTER---------------*/




.contact-section-background {
	background-color: #666;
	height: 300px;
	clip-path: polygon(0% 0%, 10% 30%, 90% 30%, 100% 0%, 100% 100%, 0% 100%);
	margin-top: -100px;
}

.contact-section {
	display: flex;
	background-color: #595959;
	margin-top: -225px;
	position: relative;
	padding-bottom: 18px;
	z-index: 1;
}

.contact, .location {
	flex-basis: 50%;
	display: flex;
	flex-direction: column;
	align-items: center;
}

.contact h1, .location h1 {
	margin: 0;
	font-family: 'Cedarville Cursive';
	color: white;
	font-size: 7rem;
}

.hex {
	-webkit-clip-path: polygon(25% 60%, 75% 60%, 100% 100%, 0% 100%);
	background-color: #17a832;
	transform: rotate(180deg);
	width: 300px;
	height: 150px;
	margin: 0 auto;
	position: absolute;
	top: 0;
	right: 0;
	left: 0;
	bottom: 0;
	z-index: 2;
}

.rhombus {
	-webkit-clip-path: polygon(50% 0%, 100% 50%, 50% 100%, 0% 50%);
	background-color: #17a832;
	width: 80px;
	height: 80px;
	position: absolute;
	margin: 0 auto;
	top: 60px;
	right: 0;
	left: 0;
	bottom: 0;
	z-index: 2;
}

.contact p {
	font-family: 'Josefin Sans';
	font-size: 2rem;
	margin-top: 0;
	margin-bottom: 10px;
	color: white;
}

.textarea {
	position: relative;
	min-width: 500px;
}

.contact textarea {
	resize: none;
	width: 100%;
	color: #595959;
	margin: 10px;
	min-height: 150px;
	font-family: 'Josefin Sans';
	font-size: 1.5rem;
	padding: 5px;
	outline: none;
	border: none;
	background: #474646;
	border-radius: 4px;
}

.contact button {
	font-size: 1.5rem;
	font-family: 'Josefin Sans';
	background: darkgrey;
	color: #595959;
	padding: 4px;
	padding-right: 6px;
	padding-left: 6px;
	border: none;
	border-radius: 4px;
	cursor: pointer;
	position: absolute;
	bottom: 10px;
	right: -20px;
	transition: all .4s ease;
}

.contact button:hover {
	color: #ddae1a;
}

.contact-line {
	margin-top: 170px;
	margin-bottom: 30px;
	width: 5px;
	border-radius: 3px;
	height: 350px;
	background: #ddae1a;
	position: relative;
}

.links {
    display: flex;
	position: relative;
	max-width: 400px;
	top: -5px;
	left: 7px;
}

.links i {
    font-size: 2.5rem;
    margin-right: 15px;
}

.links p {
    font-size: 1.5rem;
    margin-right: 30px;
    margin-top: 8px;
}

#facebook {
    color: #3b64ed;
    cursor: pointer;
}

#twitter {
    color: #5effeb;
    cursor: pointer;
}

#yelp {
    color: red;
    cursor: pointer;
}

.contact-design-wrap-left {
    position: absolute;
    left: 0;
    top: 40px;
    max-height: 500px;
}

.contact-design-wrap-right {
    position: absolute;
    bottom: 40px;
    right: 0;
    transform: rotate(180deg);
}

.contact-design-wrap-left .bottom {
    height: 0;
}

#align {
    position: absolute; 
    left: 70px; 
    top: -15px;
}

#align2 {
    position: absolute; 
    left: 68px; 
    top: -5px;
}

.grey {
    border-left: 60px solid #666;
}

.light-grey {
    border-right: 60px solid #848484;
}

.same {
    border-left: 60px solid #848484;
}

.lighter {
    border-right: 60px solid #a8a3a3;
}

.map {
    position: relative;
    top: 50px;
}

.map i {
    position: absolute;
    color: #ddae1a;
    font-size: 4rem;
    left: 50%;
    margin-left: -24px;

}

.location .map .street-1 {
    width: 300px;
    position: relative;
    top: 80px;
    height: 15px;
    transform: rotate(90deg);
    background-color: #848484;
    border-radius: 5px;
}

.location .map .street-2 {
    width: 300px;
    height: 15px;
    position: relative;
    top: 65px;
    left: 300px;
    transform: rotate(90deg);
    background-color: #848484;
    border-radius: 5px;
}

.location .map .street-3 {
    margin-top: 40px;
    width: 600px;
    position: relative;
    top: 30px;
    height: 18px;
    background-color: #848484;
    border-radius: 8px;
}

.street-info {
    color: white;
    position: absolute;
    font-family: 'Josefin Sans';
    font-size: 1.2rem;
    left: 20px;
    padding-top: 3px;
}

.address {
    position: absolute;
    left: 50%;
    top: 75px;
    margin-left: -68.5px;
    color: #ddae1a;
    text-decoration: none;
    font-family: 'Josefin Sans';
    font-size: 1.2rem;
    text-align: center;
}

.address:hover {
    color: #ddae1a;
    text-decoration: underline;
}

.copyright {
    position: absolute;
    bottom: 0;
    left: 50%;
    font-family: 'Josefin Sans';
    color: #a8a3a3;
    font-size: 1.8rem;
    padding-bottom: 5px;
    margin: 0 0 0 -253.89px;

}

Answer 1

通过background-image重设background时，也会重设所有其他属性。

要做的第一件事是仅重置background-image而不重置background，这是大多数bg属性的简写。

然后，您可能不需要重置背景大小

rightArrow.addEventListener('click', function() {
    num++;
    img.style.backgroundImage = 'url(img/fam-' + num + '.jpeg)';

})

小提琴使用lorempixel图像进行演示https://jsfiddle.net/rnxwsf2q/

Answer 2

background属性在其中包含background-x子属性的全部。

只需设置background-image。