const colors = ["green", "red", "rgba(133,122,200)", "#f15025"];
const colorIdentifier = document.querySelector('.color');
const button = document.getElementById('btn');
for (let color of colors) {
loopButton();
}
function loopButton() {
button.addEventListener('click', function() {
colorIdentifier.innerText = color;
})
};/* * {
border: 5px solid purple;
} */
/*
===============
Fonts
===============
*/
@import url("https://fonts.googleapis.com/css?family=Open+Sans|Roboto:400,700&display=swap");
/*
===============
Variables
===============
*/
:root {
/* dark shades of primary color*/
--clr-primary-1: hsl(205, 86%, 17%);
--clr-primary-2: hsl(205, 77%, 27%);
--clr-primary-3: hsl(205, 72%, 37%);
--clr-primary-4: hsl(205, 63%, 48%);
/* primary/main color */
--clr-primary-5: hsl(205, 78%, 60%);
/* lighter shades of primary color */
--clr-primary-6: hsl(205, 89%, 70%);
--clr-primary-7: hsl(205, 90%, 76%);
--clr-primary-8: hsl(205, 86%, 81%);
--clr-primary-9: hsl(205, 90%, 88%);
--clr-primary-10: hsl(205, 100%, 96%);
/* darkest grey - used for headings */
--clr-grey-1: hsl(209, 61%, 16%);
--clr-grey-2: hsl(211, 39%, 23%);
--clr-grey-3: hsl(209, 34%, 30%);
--clr-grey-4: hsl(209, 28%, 39%);
/* grey used for paragraphs */
--clr-grey-5: hsl(210, 22%, 49%);
--clr-grey-6: hsl(209, 23%, 60%);
--clr-grey-7: hsl(211, 27%, 70%);
--clr-grey-8: hsl(210, 31%, 80%);
--clr-grey-9: hsl(212, 33%, 89%);
--clr-grey-10: hsl(210, 36%, 96%);
--clr-white: #fff;
--clr-red-dark: hsl(360, 67%, 44%);
--clr-red-light: hsl(360, 71%, 66%);
--clr-green-dark: hsl(125, 67%, 44%);
--clr-green-light: hsl(125, 71%, 66%);
--clr-black: #222;
--ff-primary: "Roboto", sans-serif;
--ff-secondary: "Open Sans", sans-serif;
--transition: all 0.3s linear;
--spacing: 0.1rem;
--radius: 0.25rem;
--light-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
--dark-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
--max-width: 1170px;
--fixed-width: 620px;
}
/*
===============
Global Styles
===============
*/
*,
::after,
::before {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
font-family: var(--ff-secondary);
background: var(--clr-grey-10);
color: var(--clr-grey-1);
line-height: 1.5;
font-size: 0.875rem;
}
ul {
list-style-type: none;
}
a {
text-decoration: none;
}
h1,
h2,
h3,
h4 {
letter-spacing: var(--spacing);
text-transform: capitalize;
line-height: 1.25;
margin-bottom: 0.75rem;
font-family: var(--ff-primary);
}
h1 {
font-size: 3rem;
}
h2 {
font-size: 2rem;
}
h3 {
font-size: 1.25rem;
}
h4 {
font-size: 0.875rem;
}
p {
margin-bottom: 1.25rem;
color: var(--clr-grey-5);
}
@media screen and (min-width: 800px) {
h1 {
font-size: 4rem;
}
h2 {
font-size: 2.5rem;
}
h3 {
font-size: 1.75rem;
}
h4 {
font-size: 1rem;
}
body {
font-size: 1rem;
}
h1,
h2,
h3,
h4 {
line-height: 1;
}
}
/* global classes */
/* section */
.section {
padding: 5rem 0;
}
.section-center {
width: 90vw;
margin: 0 auto;
max-width: 1170px;
}
@media screen and (min-width: 992px) {
.section-center {
width: 95vw;
}
}
main {
min-height: 100vh;
display: grid;
place-items: center;
}
/*
===============
Nav
===============
*/
nav {
background: var(--clr-white);
height: 3rem;
display: grid;
align-items: center;
box-shadow: var(--dark-shadow);
}
.nav-center {
width: 90vw;
max-width: var(--fixed-width);
margin: 0 auto;
display: flex;
align-items: center;
justify-content: space-between;
}
.nav-center h4 {
margin-bottom: 0;
color: var(--clr-primary-5);
}
.nav-links {
display: flex;
}
nav a {
text-transform: capitalize;
font-weight: 700;
font-size: 1rem;
color: var(--clr-primary-1);
letter-spacing: var(--spacing);
margin-right: 1rem;
}
nav a:hover {
color: var(--clr-primary-5);
}
/*
===============
Container
===============
*/
main {
min-height: calc(100vh - 3rem);
display: grid;
place-items: center;
}
.container {
text-align: center;
}
.container h2 {
background: var(--clr-black);
color: var(--clr-white);
padding: 1rem;
border-radius: var(--radius);
margin-bottom: 2.5rem;
}
.color {
color: var(--clr-primary-5);
}
.btn-hero {
font-family: var(--ff-primary);
text-transform: uppercase;
background: transparent;
color: var(--clr-black);
letter-spacing: var(--spacing);
display: inline-block;
font-weight: 700;
transition: var(--transition);
border: 2px solid var(--clr-black);
cursor: pointer;
box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
border-radius: var(--radius);
font-size: 1rem;
padding: 0.75rem 1.25rem;
}
.btn-hero:hover {
color: var(--clr-white);
background: var(--clr-black);
}<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Color Flipper || Simple</title>
<!-- styles -->
<link rel="stylesheet" href="styles.css" />
</head>
<body>
<nav>
<div class="nav-center">
<h4>Color Flipper</h4>
<ul class="nav-links">
<li><a href="index.html">simple</a></li>
<li><a href="hex.html">hex</a></li>
</ul>
</div>
</nav>
<main>
<div class="container">
<h2>background color: <span class="color">#000</span></h2>
<button class="btn btn-hero" id="btn">click me</button>
</div>
</main>
<!-- javascript -->
<script src="app.js"></script>
</body>
</html>我想修改HTMLspan元素的innerText。单击button元素后，innerText会依次显示colors数组的不同颜色。
<h2>background color: <span class="color">#000</span></h2>
我使用了of循环方法。
for(let color of colors) {
loopButton();
}
function loopButton() { button.addEventListener('click', function() {
colorIdentifier.innerText = color;
}
)};
为什么说"；看起来我的帖子大部分都是代码，尽管我使用了snippet"我需要知道。我认为如果我在代码段中发布很多代码是有用的，因为人们可以看到完整的代码。
首先，您会得到Uncaught reference错误，因为事件侦听器函数是在您添加它的函数上下文之外执行的，因此它无法访问变量。一个简单的解决方法就是把它传下去：
for (const color of colors) {
loopButton(color);
}
至于颜色的实际循环，您将向同一个click事件和元素添加多个回调，因此实际上是在覆盖它们。有几种方法可以实现你想要的，但我建议在代码中保留一个计数器，并在每次按下按钮时递增。这将使color变量在每次调用回调时具有不同的值。类似于：
let counter = 0;
function callBack() {
const idx = counter % (colors.length);
colorIdentifier.innerText = colors[idx];
colorIdentifier.style.color = colors[idx];
counter++;
}
button.addEventListener('click', callBack);
您将在下面找到现在具有功能的片段。希望我已经把事情说清楚了
const colors = ["green", "red", "rgba(133,122,200)", "#f15025"];
const colorIdentifier = document.querySelector('.color');
const button = document.getElementById('btn');
let counter = 0;
function callBack() {
const idx = counter % (colors.length);
colorIdentifier.innerText = colors[idx];
colorIdentifier.style.color = colors[idx];
counter++;
}
button.addEventListener('click', callBack);/* * {
border: 5px solid purple;
} */
/*
===============
Fonts
===============
*/
@import url("https://fonts.googleapis.com/css?family=Open+Sans|Roboto:400,700&display=swap");
/*
===============
Variables
===============
*/
:root {
/* dark shades of primary color*/
--clr-primary-1: hsl(205, 86%, 17%);
--clr-primary-2: hsl(205, 77%, 27%);
--clr-primary-3: hsl(205, 72%, 37%);
--clr-primary-4: hsl(205, 63%, 48%);
/* primary/main color */
--clr-primary-5: hsl(205, 78%, 60%);
/* lighter shades of primary color */
--clr-primary-6: hsl(205, 89%, 70%);
--clr-primary-7: hsl(205, 90%, 76%);
--clr-primary-8: hsl(205, 86%, 81%);
--clr-primary-9: hsl(205, 90%, 88%);
--clr-primary-10: hsl(205, 100%, 96%);
/* darkest grey - used for headings */
--clr-grey-1: hsl(209, 61%, 16%);
--clr-grey-2: hsl(211, 39%, 23%);
--clr-grey-3: hsl(209, 34%, 30%);
--clr-grey-4: hsl(209, 28%, 39%);
/* grey used for paragraphs */
--clr-grey-5: hsl(210, 22%, 49%);
--clr-grey-6: hsl(209, 23%, 60%);
--clr-grey-7: hsl(211, 27%, 70%);
--clr-grey-8: hsl(210, 31%, 80%);
--clr-grey-9: hsl(212, 33%, 89%);
--clr-grey-10: hsl(210, 36%, 96%);
--clr-white: #fff;
--clr-red-dark: hsl(360, 67%, 44%);
--clr-red-light: hsl(360, 71%, 66%);
--clr-green-dark: hsl(125, 67%, 44%);
--clr-green-light: hsl(125, 71%, 66%);
--clr-black: #222;
--ff-primary: "Roboto", sans-serif;
--ff-secondary: "Open Sans", sans-serif;
--transition: all 0.3s linear;
--spacing: 0.1rem;
--radius: 0.25rem;
--light-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
--dark-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
--max-width: 1170px;
--fixed-width: 620px;
}
/*
===============
Global Styles
===============
*/
*,
::after,
::before {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
font-family: var(--ff-secondary);
background: var(--clr-grey-10);
color: var(--clr-grey-1);
line-height: 1.5;
font-size: 0.875rem;
}
ul {
list-style-type: none;
}
a {
text-decoration: none;
}
h1,
h2,
h3,
h4 {
letter-spacing: var(--spacing);
text-transform: capitalize;
line-height: 1.25;
margin-bottom: 0.75rem;
font-family: var(--ff-primary);
}
h1 {
font-size: 3rem;
}
h2 {
font-size: 2rem;
}
h3 {
font-size: 1.25rem;
}
h4 {
font-size: 0.875rem;
}
p {
margin-bottom: 1.25rem;
color: var(--clr-grey-5);
}
@media screen and (min-width: 800px) {
h1 {
font-size: 4rem;
}
h2 {
font-size: 2.5rem;
}
h3 {
font-size: 1.75rem;
}
h4 {
font-size: 1rem;
}
body {
font-size: 1rem;
}
h1,
h2,
h3,
h4 {
line-height: 1;
}
}
/* global classes */
/* section */
.section {
padding: 5rem 0;
}
.section-center {
width: 90vw;
margin: 0 auto;
max-width: 1170px;
}
@media screen and (min-width: 992px) {
.section-center {
width: 95vw;
}
}
main {
min-height: 100vh;
display: grid;
place-items: center;
}
/*
===============
Nav
===============
*/
nav {
background: var(--clr-white);
height: 3rem;
display: grid;
align-items: center;
box-shadow: var(--dark-shadow);
}
.nav-center {
width: 90vw;
max-width: var(--fixed-width);
margin: 0 auto;
display: flex;
align-items: center;
justify-content: space-between;
}
.nav-center h4 {
margin-bottom: 0;
color: var(--clr-primary-5);
}
.nav-links {
display: flex;
}
nav a {
text-transform: capitalize;
font-weight: 700;
font-size: 1rem;
color: var(--clr-primary-1);
letter-spacing: var(--spacing);
margin-right: 1rem;
}
nav a:hover {
color: var(--clr-primary-5);
}
/*
===============
Container
===============
*/
main {
min-height: calc(100vh - 3rem);
display: grid;
place-items: center;
}
.container {
text-align: center;
}
.container h2 {
background: var(--clr-black);
color: var(--clr-white);
padding: 1rem;
border-radius: var(--radius);
margin-bottom: 2.5rem;
}
.color {
color: var(--clr-primary-5);
}
.btn-hero {
font-family: var(--ff-primary);
text-transform: uppercase;
background: transparent;
color: var(--clr-black);
letter-spacing: var(--spacing);
display: inline-block;
font-weight: 700;
transition: var(--transition);
border: 2px solid var(--clr-black);
cursor: pointer;
box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
border-radius: var(--radius);
font-size: 1rem;
padding: 0.75rem 1.25rem;
}
.btn-hero:hover {
color: var(--clr-white);
background: var(--clr-black);
}<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Color Flipper || Simple</title>
<!-- styles -->
<link rel="stylesheet" href="styles.css" />
</head>
<body>
<nav>
<div class="nav-center">
<h4>Color Flipper</h4>
<ul class="nav-links">
<li><a href="index.html">simple</a></li>
<li><a href="hex.html">hex</a></li>
</ul>
</div>
</nav>
<main>
<div class="container">
<h2>background color: <span class="color">#000</span></h2>
<button class="btn btn-hero" id="btn">click me</button>
</div>
</main>
<!-- javascript -->
<script src="app.js"></script>
</body>
</html>由于颜色是在另一个函数上定义的，因此您无法访问它，因为let和const是块链变量-它们可以是acces
const colors = ["green", "red", "rgba(133,122,200)", "#f15025"];
const colorIdentifier = document.querySelector('.color');
const button = document.getElementById('btn');
let i = 0;
function previewColors() {
colorIdentifier.innerHTML = colors[i]; // Change innerHTML text
colorIdentifier.style.color = colors[i]; // Change innerHTML color
i++;
if( i < colors.length){
window.setTimeout(previewColors, 1000); // Access array after 1 sec if i < color.length - LOOPS over the array in recursive way- .
}
}
button.addEventListener('click', previewColors);/* * {
border: 5px solid purple;
} */
/*
===============
Fonts
===============
*/
@import url("https://fonts.googleapis.com/css?family=Open+Sans|Roboto:400,700&display=swap");
/*
===============
Variables
===============
*/
:root {
/* dark shades of primary color*/
--clr-primary-1: hsl(205, 86%, 17%);
--clr-primary-2: hsl(205, 77%, 27%);
--clr-primary-3: hsl(205, 72%, 37%);
--clr-primary-4: hsl(205, 63%, 48%);
/* primary/main color */
--clr-primary-5: hsl(205, 78%, 60%);
/* lighter shades of primary color */
--clr-primary-6: hsl(205, 89%, 70%);
--clr-primary-7: hsl(205, 90%, 76%);
--clr-primary-8: hsl(205, 86%, 81%);
--clr-primary-9: hsl(205, 90%, 88%);
--clr-primary-10: hsl(205, 100%, 96%);
/* darkest grey - used for headings */
--clr-grey-1: hsl(209, 61%, 16%);
--clr-grey-2: hsl(211, 39%, 23%);
--clr-grey-3: hsl(209, 34%, 30%);
--clr-grey-4: hsl(209, 28%, 39%);
/* grey used for paragraphs */
--clr-grey-5: hsl(210, 22%, 49%);
--clr-grey-6: hsl(209, 23%, 60%);
--clr-grey-7: hsl(211, 27%, 70%);
--clr-grey-8: hsl(210, 31%, 80%);
--clr-grey-9: hsl(212, 33%, 89%);
--clr-grey-10: hsl(210, 36%, 96%);
--clr-white: #fff;
--clr-red-dark: hsl(360, 67%, 44%);
--clr-red-light: hsl(360, 71%, 66%);
--clr-green-dark: hsl(125, 67%, 44%);
--clr-green-light: hsl(125, 71%, 66%);
--clr-black: #222;
--ff-primary: "Roboto", sans-serif;
--ff-secondary: "Open Sans", sans-serif;
--transition: all 0.3s linear;
--spacing: 0.1rem;
--radius: 0.25rem;
--light-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
--dark-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
--max-width: 1170px;
--fixed-width: 620px;
}
/*
===============
Global Styles
===============
*/
*,
::after,
::before {
margin: 0;
padding: 0;
box-sizing: border-box;
}
body {
font-family: var(--ff-secondary);
background: var(--clr-grey-10);
color: var(--clr-grey-1);
line-height: 1.5;
font-size: 0.875rem;
}
ul {
list-style-type: none;
}
a {
text-decoration: none;
}
h1,
h2,
h3,
h4 {
letter-spacing: var(--spacing);
text-transform: capitalize;
line-height: 1.25;
margin-bottom: 0.75rem;
font-family: var(--ff-primary);
}
h1 {
font-size: 3rem;
}
h2 {
font-size: 2rem;
}
h3 {
font-size: 1.25rem;
}
h4 {
font-size: 0.875rem;
}
p {
margin-bottom: 1.25rem;
color: var(--clr-grey-5);
}
@media screen and (min-width: 800px) {
h1 {
font-size: 4rem;
}
h2 {
font-size: 2.5rem;
}
h3 {
font-size: 1.75rem;
}
h4 {
font-size: 1rem;
}
body {
font-size: 1rem;
}
h1,
h2,
h3,
h4 {
line-height: 1;
}
}
/* global classes */
/* section */
.section {
padding: 5rem 0;
}
.section-center {
width: 90vw;
margin: 0 auto;
max-width: 1170px;
}
@media screen and (min-width: 992px) {
.section-center {
width: 95vw;
}
}
main {
min-height: 100vh;
display: grid;
place-items: center;
}
/*
===============
Nav
===============
*/
nav {
background: var(--clr-white);
height: 3rem;
display: grid;
align-items: center;
box-shadow: var(--dark-shadow);
}
.nav-center {
width: 90vw;
max-width: var(--fixed-width);
margin: 0 auto;
display: flex;
align-items: center;
justify-content: space-between;
}
.nav-center h4 {
margin-bottom: 0;
color: var(--clr-primary-5);
}
.nav-links {
display: flex;
}
nav a {
text-transform: capitalize;
font-weight: 700;
font-size: 1rem;
color: var(--clr-primary-1);
letter-spacing: var(--spacing);
margin-right: 1rem;
}
nav a:hover {
color: var(--clr-primary-5);
}
/*
===============
Container
===============
*/
main {
min-height: calc(100vh - 3rem);
display: grid;
place-items: center;
}
.container {
text-align: center;
}
.container h2 {
background: var(--clr-black);
color: var(--clr-white);
padding: 1rem;
border-radius: var(--radius);
margin-bottom: 2.5rem;
}
.color {
color: var(--clr-primary-5);
}
.btn-hero {
font-family: var(--ff-primary);
text-transform: uppercase;
background: transparent;
color: var(--clr-black);
letter-spacing: var(--spacing);
display: inline-block;
font-weight: 700;
transition: var(--transition);
border: 2px solid var(--clr-black);
cursor: pointer;
box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
border-radius: var(--radius);
font-size: 1rem;
padding: 0.75rem 1.25rem;
}
.btn-hero:hover {
color: var(--clr-white);
background: var(--clr-black);
}<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8" />
<meta name="viewport" content="width=device-width, initial-scale=1.0" />
<title>Color Flipper || Simple</title>
<!-- styles -->
<link rel="stylesheet" href="styles.css" />
</head>
<body>
<nav>
<div class="nav-center">
<h4>Color Flipper</h4>
<ul class="nav-links">
<li><a href="index.html">simple</a></li>
<li><a href="hex.html">hex</a></li>
</ul>
</div>
</nav>
<main>
<div class="container">
<h2>background color: <span class="color">#000</span></h2>
<button class="btn btn-hero" id="btn">click me</button>
</div>
</main>
<!-- javascript -->
<script src="app.js"></script>
</body>
</html>好吧，您想做的是点击按钮来显示数组中的下一种颜色吗？如果是，那么这就是javascript
const colors = ["green", "red", "rgba(133,122,200)", "#f15025"]
const colorIdentifier = document.querySelector(".color")
const button = document.getElementById("btn")
// global index for so we can iterate array 1 by 1
let index = 0
// button on click event listener
button.addEventListener("click", () => {
// set the text of colorIdentifier to colors and use the index of how many times we clicked the button
colorIdentifier.textContent = colors[index]
// iterate the button for on each click this is shorthand for index = index + 1
index++
// check to see if the index is bigger then the length and resets it back to 0
if (index >= colors.length) index = 0
})