我一直在尝试开发一个电子邮件和密码，并(目前(，如果电子邮件是一封电子邮件，只是通过查看用户是否包含"@@in in in in in提交。据说，如果没有"@"，则包含文本框标题"电子邮件"标题的段落标签应更改颜色。不幸的是，事实并非如此，我不知道为什么是这种情况。我尝试了几种改变颜色的方式，但都失败了。如果有人可以帮助我解决这个问题，那将使我一天。
我已经尝试使用不同的验证方法和不同的方法来更改段落标签的样式。例如，我尝试使用一个单独的样式代码，当未找到"@"符号时，段落应该从默认样式代码中切换两个样式代码。我还尝试使用不同的时间，即JS代码将像Onsubmit或Onblur一样运行。这些更改无法解决我的问题。
html, body { height: 100%; }
body {
background:radial-gradient(ellipse at center,
rgba(255,254,234,1) 0%, rgba(255,254,234,1) 35%, #ffffff 100%);
overflow: hidden;
}
.ocean {
height: 5%;
width:100%;
position:absolute;
bottom:0;
left:0;
background: #ffffff;
}
.wave {
background: url(https://s3-us-west-
2.amazonaws.com/s.cdpn.io/85486/wave.svg) repeat-x;
position: absolute;
top: -198px;
width: 6400px;
height: 198px;
animation: wave 7s cubic-bezier( 0.36, 0.45, 0.63, 0.53)
infinite;
transform: translate3d(0, 0, 0);
}
.wave:nth-of-type(2) {
top: -175px;
animation: wave 7s cubic-bezier( 0.36, 0.45, 0.63, 0.53)
-.125s infinite, swell 7s ease -1.25s infinite;
opacity: 1;
}
@keyframes wave {
0% {
margin-left: 0;
}
100% {
margin-left: -1600px;
}
}
@keyframes swell {
0%, 100% {
transform: translate3d(0,-25px,0);
}
50% {
transform: translate3d(0,5px,0);
}
}
.loginbox
{
width: 340px;
height: 360px;
background: #000;
color: #fff;
top: 50%;
left:50%;
position: absolute;
transform: translate(-50%, -50%);
box-sizing: border-box;
}
h2
{
margin: 0;
padding: 0 0 20px;
text-align: center;
font-size: 22px;
}
.loginbox input
{
width: 100%;
margin-bottom: 20px;
}
.loginbox input[type="text"], input[type="password"]
{
border: none;
border-bottom: 1px solid #fff;
background: transparent;
outline: none;
height: 40px;
color: #fff;
font-size: 16px;
}
.loginbox input[type="submit"]
{
border: none;
outline: none;
height: 48px;
background: #fb2525;
color: #fff;
font-size: 18px;
border-radius: 20px;
}
.loginbox input[type="submit"]:hover
{
cursor: pointer;
background: #ffc107;
color: #000;
}
.loginbox a
{
text-decoration: none;
font-size: 12px;
line-height: 20px;
color: darkgrey;
}
.loginbox p
{
margin: 0;
padding: 10px;
font-weight: bold;
}
.loginbox a:hover
{
color: #ffc107;
} <!DOCTYPE html>
<html>
<head>
<title>
Sign Up Page
</title>
<link rel="stylesheet" href="style.css" media="screen"/>
</head>
<body>
<script>
function validateForm() {
var x = document.forms["myForm"]["fname"].value;
if (x == "") {
alert("something must be filled out");
return false;
}
else if (!(x.includes("@")))
{
alert("");
document.getElementById("nameT").className="error";
return false;
}
}
</script>
<div class="ocean">
<div class="wave"></div>
<div class="wave"></div>
</div>
<h1>
<center>
Whale
</center>
</h1>
<div class="loginbox">
<h2>
Login
</h2>
<form name="myForm" onsubmit="return validateForm()"
method="post">
<p name="nameT"> email </p>
<input type="text" name="fname" placeholder="enter
email" onblur="validateForm()">
<p name="passT"> password </p>
<input type="text" name="name" placeholder="enter
password">
<br>
<input type="submit" value="Submit">
<br>
<a href="#">
Lost your password?
</a>
<br>
<a href="#">
Create an account
</a>
</form>
</div>
</body>
</html>当我单击"电子邮件"框时，警报消息将使文本不会更改颜色。我知道的没有错误消息弹出。几乎就像跳过更改颜色代码一样。
您可以尝试这样的尝试：
function validateForm() {
var x = document.forms["myForm"]["fname"].value;
if (x == "") {
alert("something must be filled out");
return false;
}
else if (!(x.includes("@")))
{
alert("you must have to filled value with @");
document.getElementById("nameT").style.color="red";
return false;
}
} html, body { height: 100%; }
body {
background:radial-gradient(ellipse at center,
rgba(255,254,234,1) 0%, rgba(255,254,234,1) 35%, #ffffff 100%);
overflow: hidden;
}
.ocean {
height: 5%;
width:100%;
position:absolute;
bottom:0;
left:0;
background: #ffffff;
}
.wave {
background: url(https://s3-us-west-
2.amazonaws.com/s.cdpn.io/85486/wave.svg) repeat-x;
position: absolute;
top: -198px;
width: 6400px;
height: 198px;
animation: wave 7s cubic-bezier( 0.36, 0.45, 0.63, 0.53)
infinite;
transform: translate3d(0, 0, 0);
}
.wave:nth-of-type(2) {
top: -175px;
animation: wave 7s cubic-bezier( 0.36, 0.45, 0.63, 0.53)
-.125s infinite, swell 7s ease -1.25s infinite;
opacity: 1;
}
@keyframes wave {
0% {
margin-left: 0;
}
100% {
margin-left: -1600px;
}
}
@keyframes swell {
0%, 100% {
transform: translate3d(0,-25px,0);
}
50% {
transform: translate3d(0,5px,0);
}
}
.loginbox
{
width: 340px;
height: 360px;
background: #000;
color: #fff;
top: 50%;
left:50%;
position: absolute;
transform: translate(-50%, -50%);
box-sizing: border-box;
}
h2
{
margin: 0;
padding: 0 0 20px;
text-align: center;
font-size: 22px;
}
.loginbox input
{
width: 100%;
margin-bottom: 20px;
}
.loginbox input[type="text"], input[type="password"]
{
border: none;
border-bottom: 1px solid #fff;
background: transparent;
outline: none;
height: 40px;
color: #fff;
font-size: 16px;
}
.loginbox input[type="submit"]
{
border: none;
outline: none;
height: 48px;
background: #fb2525;
color: #fff;
font-size: 18px;
border-radius: 20px;
}
.loginbox input[type="submit"]:hover
{
cursor: pointer;
background: #ffc107;
color: #000;
}
.loginbox a
{
text-decoration: none;
font-size: 12px;
line-height: 20px;
color: darkgrey;
}
.loginbox p
{
margin: 0;
padding: 10px;
font-weight: bold;
}
.loginbox a:hover
{
color: #ffc107;
}<!DOCTYPE html>
<html>
<head>
<title>
Sign Up Page
</title>
<link rel="stylesheet" href="style.css" media="screen"/>
</head>
<body>
<div class="ocean">
<div class="wave"></div>
<div class="wave"></div>
</div>
<h1>
<center>
Whale
</center>
</h1>
<div class="loginbox">
<h2>
Login
</h2>
<form name="myForm" onsubmit="return validateForm()"
method="post">
<p id="nameT"> email </p>
<input type="text" name="fname" placeholder="enter
email" onblur="validateForm()">
<p name="passT"> password </p>
<input type="text" name="name" placeholder="enter
password">
<br>
<input type="submit" value="Submit">
<br>
<a href="#">
Lost your password?
</a>
<br>
<a href="#">
Create an account
</a>
</form>
</div>
</body>
</html>您必须将名称更改为ID for Email，并添加一个错误，请检查以下代码
<script>
function validateForm() {
var x = document.forms["myForm"]["fname"].value;
if (x == "") {
alert("something must be filled out");
return false;
}
else if (!(x.includes("@")))
{
alert("");
document.getElementById("nameT").className="error";
return false;
}
}
</script>
<div class="ocean">
<div class="wave"></div>
<div class="wave"></div>
</div>
<h1>
<center>
Whale
</center>
</h1>
<div class="loginbox">
<h2>
Login
</h2>
<form name="myForm" onsubmit="return validateForm()"
method="post">
<p id="nameT"> email </p>
<input type="text" name="fname" placeholder="enter
email" onblur="validateForm()">
<p name="passT"> password </p>
<input type="text" name="name" placeholder="enter
password">
<br>
<input type="submit" value="Submit">
<br>
<a href="#">
Lost your password?
</a>
<br>
<a href="#">
Create an account
</a>
</form>
</div>