我是 bootstrap 的初学者，我见过很多 bootstrap 3 表单验证插件等，但我还没有找到任何用于 bootstrap 4 的插件。
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:lorem@ipsum.com">
<h4 id="mail">lorem@ipsum.com</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>我曾尝试修改现有的js，但我没有运气。
这是呈现的形式:
最佳答案
首先，我使用像 Jonathan Dion 这样的外部库解决了我的问题建议。但最近我遇到了这个:
Bootstrap v4.0 引入了他们自己的表单验证，您仍然可以将其与后端 php 验证配对。来自Doc :
<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>
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>
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 block 。它通过 CSS 的两个伪类应用，:invalid和 :valid .适用于 <input> , <select> , 和 <textarea>元素。
关于javascript - Bootstrap 4 表单验证，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/43481237/