Javascript Bootstrap 4 表单验证
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Bootstrap 4 Form Validation
提问by Cédric MEYER
I'm a beginner with bootstrap and I have seen a lot of bootstrap 3 form validation plugins etc, but I haven't found any for bootstrap 4.
我是 bootstrap 的初学者，我见过很多 bootstrap 3 表单验证插件等，但我没有找到任何用于 bootstrap 4 的插件。
I'm trying to validate multiple forms, and here is my code:
我正在尝试验证多个表单，这是我的代码：
<!-- Contact -->
<div class="container white">
<div class="row">
<div class="container white percent100">
<div class="col-lg-12">
<div class="padder-t2">
<h1>Contact</h1>
<div class="horiz-divider"></div>
</div>
</div>
</div>
</div>
<div class="row padder-t padder-b">
<div class="container white">
<div class="col-lg-12">
<!-- Form -->
<form class="form-horizontal" action=" " method="post" id="contact_form">
<fieldset>
<!-- Text input-->
<div class="form-group">
<div class="row">
<div class="col-md-4 col-lg-4">
<label class="control-label pull-right"><h4>First Name</h4></label>
</div>
<div class="col-md-4 col-lg-4 inputGroupContainer">
<div class="input-group">
<span class="input-group-addon"><i class="fa fa-user"></i></span>
<input id="firstname" name="firstname" placeholder="First Name" class="form-control" type="text">
</div>
</div>
</div>
</div>
<!-- Text input-->
<div class="form-group">
<div class="row">
<div class="col-md-4 col-lg-4">
<label class="control-label pull-right"><h4>Last Name</h4></label>
</div>
<div class="col-md-4 col-lg-4 inputGroupContainer">
<div class="input-group">
<span class="input-group-addon"><i class="fa fa-user"></i></span>
<input id="lastname" name="lastname" placeholder="Last Name" class="form-control" type="text">
</div>
</div>
</div>
</div>
<!-- Text input-->
<div class="form-group">
<div class="row">
<div class="col-md-4 col-lg-4">
<label class="control-label pull-right"><h4>E-Mail</h4></label>
</div>
<div class="col-md-4 col-lg-4 inputGroupContainer">
<div class="input-group">
<span class="input-group-addon"><i class="fa fa-envelope"></i></span>
<input id="email" name="email" placeholder="E-Mail Address" class="form-control" type="email">
</div>
</div>
</div>
</div>
<!-- Text input-->
<div class="form-group">
<div class="row">
<div class="col-md-4 col-lg-4">
<label class="control-label pull-right"><h4>Phone #</h4></label>
</div>
<div class="col-md-4 col-lg-4 inputGroupContainer">
<div class="input-group">
<span class="input-group-addon"><i class="fa fa-phone"></i></span>
<input id="phone" name="phone" placeholder="Phone" class="form-control" type="text">
</div>
</div>
</div>
</div>
<!-- Text area -->
<div class="form-group">
<div class="row">
<div class="col-md-4 col-lg-4">
<label class="control-label pull-right"><h4>Message</h4></label>
</div>
<div class="col-md-4 col-lg-5 inputGroupContainer">
<div class="input-group">
<span class="input-group-addon"><i class="fa fa-pencil"></i></span>
<textarea id="comment" class="form-control" name="comment" placeholder="Your Message"></textarea>
</div>
</div>
</div>
</div>
<!-- Success message -->
<div class="alert alert-success" role="alert" id="success_message">Success <i class="fa fa-thumbs-up"></i> Thanks for contacting us, we will get back to you shortly.</div>
<!-- Button -->
<div class="form-group">
<div class="row">
<label class="col-md-4 col-lg-4 control-label"></label>
<div class="col-md-4 col-lg-4">
<button type="submit" class="btn btn-danger raised">Send <i class="fa fa-paper-plane"></i></button>
</div>
</div>
</div>
</fieldset>
</form>
</div>
</div>
</div>
<div class="row padder-b">
<div class="row col-lg-12">
<div class="col-md-3 col-lg-3"></div>
<h4 class="col-md-9 col-lg-9">Contact us directly:</h4>
</div>
<div class="row col-lg-12">
<div class="col-md-3 col-lg-3"></div>
<h4 class="col-md-2 col-lg-2 padder-lr">Mail:</h4>
<a class="col-md-6 col-lg-6 padder-lr" href="mailto:[email protected]">
<h4 id="mail">[email protected]</h4>
</a>
</div>
<div class="row col-lg-12">
<div class="col-md-3 col-lg-3"></div>
<h4 class="col-md-2 col-lg-2 padder-lr">Adress:</h4>
<h4 class="col-md-6 col-lg-6 padder-lr" id="adress">2 LoremIpsum Road, 67000 City - Country</h4>
</div>
</div>
</div>I have tried to modify existing js, but I had no luck.
我试图修改现有的 js，但我没有运气。
Here is the rendered form:
这是呈现的形式：
回答by Cédric MEYER
First I solved my issue with an external library like Jonathan Dionsuggested. But recently I came across this :
首先，我使用Jonathan Dion建议的外部库解决了我的问题。但最近我遇到了这个：
Bootstrap v4.0introduced their own form validation that you can still pair with backend php validation. From the Doc:
Bootstrap v4.0引入了他们自己的表单验证，您仍然可以与后端 php 验证配对。从文档：
<form class="needs-validation" novalidate>
<div class="form-row">
<div class="col-md-4 mb-3">
<label for="validationCustom01">First name</label>
<input type="text" class="form-control" id="validationCustom01" placeholder="First name" value="Mark" required>
<div class="valid-feedback">
Looks good!
</div>
<div class="invalid-feedback">
Doesn't look good!
</div>
</div>
</div>
</div>
Then using JS :
然后使用JS：
<script>
// Example starter JavaScript for disabling form submissions if there are invalid fields
(function() {
'use strict';
window.addEventListener('load', function() {
// Fetch all the forms we want to apply custom Bootstrap validation styles to
var forms = document.getElementsByClassName('needs-validation');
// Loop over them and prevent submission
var validation = Array.prototype.filter.call(forms, function(form) {
form.addEventListener('submit', function(event) {
if (form.checkValidity() === false) {
event.preventDefault();
event.stopPropagation();
}
form.classList.add('was-validated');
}, false);
});
}, false);
})();
</script>
This provides input border colorating and displays the valid / invalid feedback blocks according to the given pattern or properties. It is applied via CSS's two pseudo-classes, :invalidand :valid. It applies to <input>, <select>, and <textarea>elements.
这提供了输入边框着色并根据给定的模式或属性显示有效/无效的反馈块。它通过 CSS 的两个伪类:invalid和:valid. 它适用于<input>，<select>和<textarea>元素。
回答by Zim
Update 2020- Bootstrap 4.4.x
2020年更新- Bootstrap 4.4.x
Here's another option (modern JS) if you want to validate each input one at a time (liveor real-time) instead of waiting for the entire form to be submitted...
如果您想一次（实时或实时）验证每个输入，而不是等待整个表单提交，这是另一种选择（现代 JS）...
(function() {
'use strict';
window.addEventListener('load', function() {
// fetch all the forms we want to apply custom style
var inputs = document.getElementsByClassName('form-control')
// loop over each input and watch blue event
var validation = Array.prototype.filter.call(inputs, function(input) {
input.addEventListener('blur', function(event) {
// reset
input.classList.remove('is-invalid')
input.classList.remove('is-valid')
if (input.checkValidity() === false) {
input.classList.add('is-invalid')
}
else {
input.classList.add('is-valid')
}
}, false);
});
}, false);
})()
<form class="container" novalidate="" action="/echo" method="POST" id="myForm">
<div class="form-group">
<label class="form-control-label" for="input1">Enter some input</label>
<input type="text" class="form-control" name="input1" id="input1"
autocomplete="no" required>
<div class="valid-feedback">Success! You've done it.</div>
<div class="invalid-feedback">No, you missed this one.</div>
</div>
<div class="form-group">
<label class="form-control-label" for="input2">Enter password</label>
<input type="text" class="form-control"
pattern="^(?=.*\d)(?=.*[a-z])(?=.*[A-Z]).{6,}$"
autocomplete="no" name="input2" id="input2">
<div class="valid-feedback">Nice! You got this one!</div>
<div class="invalid-feedback">At least 6 chars: 1 uppercase, 1 lowercase and numeric</div>
</div>
<div>
<button type="submit" class="btn btn-secondary" id="btnSubmit">Submit</button>
</div>
</form>
回答by Jonathan Dion
You can use any library available on the web.You may try jqueryvalidation. It's pretty easy to use, just read the documentation.
您可以使用网络上可用的任何库。你可以试试jqueryvalidation。它非常易于使用，只需阅读文档即可。
Add the requiredattribute on your inputand jqueryvalidation will do the job. For styling, you can add your own CSS and make it look like bootstrap.
required在您的input和 jqueryvalidation上添加属性将完成这项工作。对于样式，您可以添加自己的 CSS 并使其看起来像引导程序。
Hopes it help
希望有帮助
$(document).ready(function(){
$('#contact_form').validate()
})
回答by Juan Marco
I found a simpler and a bit more modern way to implement Bootstrap 4 JS Form validation:
我找到了一种更简单、更现代的方式来实现Bootstrap 4 JS 表单验证：
Note: Keep in mind that each <form>element must have the novalidateattribute and at the same time, each <input>element in it must have the requiredattribute.
注意：请记住，每个<form>元素都必须具有该novalidate属性，同时，其中的每个<input>元素都必须具有该required属性。
// Upon load..
window.addEventListener('load', () => {
// Grab all the forms
var forms = document.getElementsByClassName('needs-validation');
// Iterate over each one
for (let form of forms) {
// Add a 'submit' event listener on each one
form.addEventListener('submit', (evt) => {
// check if the form input elements have the 'required' attribute
if (!form.checkValidity()) {
evt.preventDefault();
evt.stopPropagation();
console.log('Bootstrap will handle incomplete form fields');
} else {
// Since form is now valid, prevent default behavior..
evt.preventDefault();
console.info('All form fields are now valid...');
}
form.classList.add('was-validated');
});
}
});<!-- Load necessary libraries -->
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css">
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"></script>
<!-- Add form -->
<div class="container" style="padding-top: 40px;">
<form class="student-search needs-validation" novalidate>
<div class="form-row">
<div class="form-group col-6">
<label for="input-name-search" class="sr-only">Name</label>
<input type="text" class="form-control" id="input-name-search" placeholder="Name" required>
<div class="valid-feedback">Looks good!</div>
<div class="invalid-feedback">Enter a name please.</div>
</div>
<div class="col-6">
<button id="btn-search" type="submit" class="btn btn-success btn-block">Search student</button>
</div>
</div>
</form>
</div>回答by phoenix
I just figured out the reason my code wasn't validating: I didn't have a submit button to trigger the validation. Make sure to have it.
我刚刚弄清楚我的代码没有验证的原因：我没有提交按钮来触发验证。确保拥有它。
<button type="submit" class="btn btn-primary">Save</button>
