我有一个覆盖搜索框(检查代码(。搜索框有一个占位符"Sök"，假设用户在文本框中写了一些东西，但随后退出(按右上角的 x(。然后，我希望删除用户编写的文本并重置占位符，因此每当用户再次进入搜索框时，文本都会被删除，占位符会恢复。如何创建此事件？法典：
body{
background: white;
font-family: 'Montserrat', sans-serif;
padding-bottom: -1px;
}
span{
display: inline-block;
}
.backgroundlogo{
margin-top:-1400px;
z-index: -1;
position: relative;
width: 100%;
}
.container{
width: 80%;
margin: 0 auto;
}
header{
background: none;
}
* {
margin:0;
padding:0;
}
header ::after {
content: "";
display: table;
clear: both;
}
nav{
float: right;
padding-right: 230px;
}
nav li{
display: inline-block;
padding-left: 45px;
padding-top: 20px;
padding-bottom: 20px;
}
nav ul{
list-style: none;
display: inline-block;
padding-top: 25px;
}
nav a {
font-size: 12px;
color: black;
font-weight: 600;
text-decoration: none;
text-align: center;
text-transform: uppercase;
}
nav a:hover{
color: red;
}
nav li:hover{
}
.fa-bars{
color: black;
font-size: 14px;
padding-left: 15px;
}
.fa-bars:hover{
color: red;
cursor: pointer;
}
.wrapper{
position: relative;
height: 100%;
width: 100%;
}
.backgroundlogo{
}
.bild1{
height: 350px;
width: 600px;
margin-top: 100px;
margin-left: 80px;
position: absolute;
z-index: 4;
background-image: url('Img/KBA.jpg');
background-position: 10% 30% ;
background-size: 180%;
}
.bild2{
height: 350px;
width: 600px;
margin-top: 140px;
margin-left: 120px;
z-index: 3;
position:absolute;
background-color: #3D6BB8;
}
.entrytext{
float: right;
margin-right: 90px;
margin-top: 175px;
clear: both;
}
.entrytext>h1{
font-weight: 800;
font-style: normal;
font-size: 54px;
}
.entrytext>button{
border: none;
display: inline-block;
background-color: #38b272;
color: white;
padding: 8px 10px 8px 15px;
letter-spacing: 6px;
border-radius: 8px;
font-weight: 500;
font-size: 17px;
text-align: left;
margin-top: 20px;
box-shadow: 20px 15px black;
}
.entrytext>button:hover{
border: none;
display: inline-block;
background-color: #c12147;
color: white;
padding: 8px 10px 8px 15px;
letter-spacing: 6px;
border-radius: 8px;
font-weight: 500;
font-size: 17px;
text-align: left;
margin-top: 20px;
}
button:focus {outline:0;}
.fa-angle-right{
font-size: 20px;
padding-left: 30px;
}
.entrytext>h2{
font-size: 14px;
font-weight: 600;
margin-top: 20px;
}
.citygalleria{
color: #CC2244;
}
.brand{
height: 110px;
width: 750px;
margin: 600px auto;
background-color: #CFCFCF;
clear: both;
z-index: 11;
}
.openBtn {
background: #f1f1f1;
border: none;
padding: 10px 15px;
font-size: 20px;
cursor: pointer;
}
.openBtn:hover {
background: #bbb;
}
.overlay {
height: 100%;
width: 100%;
display: none;
position: fixed;
z-index: 10;
top: 0;
left: 0;
background-color: white;
background-color: rgba(255,255,255, 0.8);
}
.overlay-content {
position: relative;
top: 20%;
width: 80%;
text-align: center;
margin-top: 30px;
margin: auto;
}
.overlay .closebtn {
position: absolute;
top: 20px;
right: 45px;
font-size: 60px;
cursor: pointer;
color: black;
}
.overlay .closebtn:hover {
color: #ccc;
}
.overlay input[type=text] {
padding: 15px;
font-size: 50px;
font-weight: bold;
border: none;
background:none;
margin: 0 auto;
text-decoration: none;
border-bottom: 6px solid black;
border-bottom-left-radius: 5px;
color:black;
text-align:center;
width: 100%;
}
input::placeholder {
color: black;
}
.overlay input[type=text]:hover {
background: none;
}
.overlay button {
float: left;
width: 20%;
padding: 15px;
background: #ddd;
font-size: 17px;
border: none;
cursor: pointer;
}
input:focus {outline:0;}
.overlay button:hover {
background: #bbb;
}
.type1{
width: 1700px;
}<!DOCTYPE html>
<html lang="en" dir="ltr">
<head>
<link rel="stylesheet" href="style.css" type="text/css">
<meta charset="utf-8">
<script src="https://kit.fontawesome.com/908c2e5c96.js"></script>
<link href="https://fonts.googleapis.com/css?family=Montserrat:100,100i,200,200i,300,300i,400,400i,500,500i,600,600i,700,700i,800,800i,900,900i&display=swap" rel="stylesheet">
<link rel="stylesheet" type="text/css" href="slick/slick.css"/>
<title>Kungsmässan — Måste upplevas!</title>
</head>
<body>
<header>
<div class="container">
<nav>
<ul>
<li><a href="#">Butiker</a></li>
<li><a href="#">Resturang & Café</a></li>
<li><a href="#">Utbyggnad</a></li>
<li><a href="#">Öppetider</a></li>
<div id="myOverlay" class="overlay">
<span class="closebtn" onclick="closeSearch()" title="Close Overlay">×</span>
<div class="overlay-content">
<form action="/action_page.php">
<input class="type1" id="type2" onblur="this.placeholder = 'Sök'" onfocus="this.placeholder = ''" type="text" placeholder="Sök" name="search">
</form>
</div>
</div>
<i onclick="openSearch()" id="openBtn" class="fas fa-search"></i>
<script>
function openSearch() {
document.getElementById("myOverlay").style.display = "block";
}
document.addEventListener('keydown',function(){document.getElementById('type2').focus();});
function closeSearch() {
document.getElementById("myOverlay").style.display = "none";
}
</script>
<i class="fas fa-bars"></i>
</ul>
</nav>
</div>
</header>
<div class="bild1">
</div>
<div class="bild2">
</div>
<div class="entrytext">
<h1>Sveriges bästa <br/> <span class="citygalleria">citygalleria.</span> Mitt <br/> i Kungsbacka.</h1>
<h2>35 000 KVADRATMETER OCH ÖVER 100 AFFÄRER!</h2>
<button type="LÄS MER" name="button ">LÄS MER<i class="fas fa-angle-right"></i></button>
</div>
<div class="brand">
</div>
<span>
<img class="backgroundlogo" src="Img/bg.png" alt="">
</span>
</body>
</html>如果在单击关闭按钮时将输入的值设置回无，则占位符应再次出现：
const button = document.querySelector( 'button' );
const input = document.querySelector( 'input' );
button.addEventListener( 'click', event => {
input.value = '';
});<input type="text" placeholder="Sok">
<button>Close</button>尝试使用 setValue(''( 方法重置任何元素值。