<html>
<script>
function passwordvalidation() #validate if password is strong and if botth passwords are equal
{
var x=document.forms["signup"]["psw"].value;
var y=document.form["signup"]["psw-repeat"].value;
var z=document.form["signup"]["email"].value;
alert(x);
if (x == ""||y==""||z=="") {
alert("form must be filled out");
return false;
}
else if(y!=x)
{
alert("password does not match");
return false;
}
else if (!(x.match(/[a-z]/g) && x.match(
/[A-Z]/g) && x.match(
/[0-9]/g) && x.match(
/[^a-zA-Z\d]/g) && x.length >= 8))
{
alert("weak password")
return false;
}
else
{
return true;
}
}
</script>
<style>
body {font-family: Arial, Helvetica, sans-serif;}
* {box-sizing: border-box}
/* Full-width input fields */
input[type=text], input[type=password] {
width: 100%;
padding: 15px;
margin: 5px 0 22px 0;
display: inline-block;
border: none;
background: #f1f1f1;
}
input[type=text]:focus, input[type=password]:focus {
background-color: #ddd;
outline: none;
}
hr {
border: 1px solid #f1f1f1;
margin-bottom: 25px;
}
/* Set a style for all buttons */
button {
background-color: #4CAF50;
color: white;
padding: 14px 20px;
margin: 8px 0;
border: none;
cursor: pointer;
width: 100%;
opacity: 0.9;
}
button:hover {
opacity:1;
}
/* Extra styles for the cancel button */
.cancelbtn {
padding: 14px 20px;
background-color: #f44336;
}
/* Float cancel and signup buttons and add an equal width */
.cancelbtn, .signupbtn {
float: left;
width: 50%;
}
/* Add padding to container elements */
.container {
padding: 16px;
}
/* Clear floats */
.clearfix::after {
content: "";
clear: both;
display: table;
}
/* Change styles for cancel button and signup button on extra small screens */
@media screen and (max-width: 300px) {
.cancelbtn, .signupbtn {
width: 100%;
}
}
</style>
<body>
<form name="signup" action="/login" onsubmit="return passwordvalidation()" style="border:1px solid #ccc">
<div class="container">
<h1>Sign Up</h1>
<h6>Please fill in this form to create an account.</h6>
<p>Strong password must contain 8 characters </p>
<hr>
<label for="email"><b>Email</b></label>
<input type="text" placeholder="Enter Email" name="email" required>
<label for="psw"><b>Password</b></label>
<input type="password" placeholder="Enter Password" name="psw" required>
<label for="psw-repeat"><b>Repeat Password</b></label>
<input type="password" placeholder="Repeat Password" name="psw-repeat" required>
<div class="clearfix">
<button type="submit" class="signupbtn">Sign Up</button>
</div>
</div>
</form>
</body>
</html>
你的这几行有几个错误。
var x=document.forms["signup"]["psw"].value;
var y=document.form["signup"]["psw-repeat"].value;
var z=document.form["signup"]["email"].value;
你可以使用很多方法来获取输入值，但这种方式会出错。检查一下如何使用document.getElementBy***或类似的方法来进行操作
它是在调用验证函数，但你在第二行和第三行犯了一个拼写错误。改正document.form -->.是未定义的，当你调用时，你的函数以TypeError退出。document.forms document.form 是未定义的，当你调用 document.form["signup"] 而不返回false，这样你的表单就会导航到定义的动作。
function passwordvalidation(form)
{
var x=form["psw"].value;
var y=form["psw-repeat"].value;
var z=form["email"].value;
if (x == ""||y==""||z=="") {
alert("form must be filled out");
console.log("form must be filled out");
return false;
}
else if(y!=x)
{
alert("password does not match");
return false;
}
else if (!(x.match(/[a-z]/g) && x.match(
/[A-Z]/g) && x.match(
/[0-9]/g) && x.match(
/[^a-zA-Z\d]/g) && x.length >= 8))
{
alert("weak password")
return false;
}
else
{
return true;
}
}body {font-family: Arial, Helvetica, sans-serif;}
* {box-sizing: border-box}
/* Full-width input fields */
input[type=text], input[type=password] {
width: 100%;
padding: 15px;
margin: 5px 0 22px 0;
display: inline-block;
border: none;
background: #f1f1f1;
}
input[type=text]:focus, input[type=password]:focus {
background-color: #ddd;
outline: none;
}
hr {
border: 1px solid #f1f1f1;
margin-bottom: 25px;
}
/* Set a style for all buttons */
button {
background-color: #4CAF50;
color: white;
padding: 14px 20px;
margin: 8px 0;
border: none;
cursor: pointer;
width: 100%;
opacity: 0.9;
}
button:hover {
opacity:1;
}
/* Extra styles for the cancel button */
.cancelbtn {
padding: 14px 20px;
background-color: #f44336;
}
/* Float cancel and signup buttons and add an equal width */
.cancelbtn, .signupbtn {
float: left;
width: 50%;
}
/* Add padding to container elements */
.container {
padding: 16px;
}
/* Clear floats */
.clearfix::after {
content: "";
clear: both;
display: table;
}
/* Change styles for cancel button and signup button on extra small screens */
@media screen and (max-width: 300px) {
.cancelbtn, .signupbtn {
width: 100%;
}
}<form name="signup" action="/login" onsubmit="return passwordvalidation(this)" style="border:1px solid #ccc">
<div class="container">
<h1>Sign Up</h1>
<h6>Please fill in this form to create an account.</h6>
<p>Strong password must contain 8 characters </p>
<hr>
<label for="email"><b>Email</b></label>
<input type="text" placeholder="Enter Email" name="email" required>
<label for="psw"><b>Password</b></label>
<input type="password" placeholder="Enter Password" name="psw" required>
<label for="psw-repeat"><b>Repeat Password</b></label>
<input type="password" placeholder="Repeat Password" name="psw-repeat" required>
<div class="clearfix">
<button type="submit"class="signupbtn">Sign Up</button>
</div>
</div>
</form>