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<!-- code from bootstrap documentation -->
<form class="needs-validation" id="validation-test">
<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="" required data-pattern="text">
<div class="valid-feedback">
Looks good!
</div>
<div class="invalid-feedback">
please enter a valid name
</div>
</div>
<div class="col-md-4 mb-3">
<label for="validationCustom02">Numbers</label>
<input type="text" class="form-control" id="validationCustom02" placeholder="numbers" value="" required data-pattern="numbers">
<div class="valid-feedback">
Looks good!
</div>
<div class="invalid-feedback">
please enter a valid number
</div>
</div>
<div class="col-md-4 mb-3">
<label for="validationCustomUsername">Email</label>
<div class="input-group">
<div class="input-group-prepend">
<span class="input-group-text" id="inputGroupPrepend">@</span>
</div>
<input type="text" class="form-control" id="validationCustomUsername" placeholder="Email" aria-describedby="inputGroupPrepend" required data-pattern="email">
<div class="invalid-feedback">
please enter a valid email address
</div>
<div class="valid-feedback">
Looks good!
</div>
</div>
</div>
</div>
<div class="form-group">
<div class="form-check">
<input class="form-check-input" type="checkbox" value="" id="invalidCheck" required>
<label class="form-check-label" for="invalidCheck">
Agree to terms and conditions
</label>
<div class="invalid-feedback">
You must agree before submitting.
</div>
</div>
</div>
<button class="btn btn-primary" type="submit">Submit form</button>
</form>
form {
padding: 20px;
}
class FormValidator {
constructor(config) {
/**
* @description creates new validation model and provides validation patterns
* @type {FormValidatorModel} config
*/
this.config = new FormValidatorModel(config);
/**
* @description form elements
* @type {HTMLElement} form
*/
this.form = document.querySelector(this.config.selector);
/**
* @description form element
* @type {NodeList} inputs
*/
this.inputs = this.form.querySelectorAll(this.config.inputTypes);
/**
* @description init validation script
*/
this._init();
}
_init() {
// disable HTML5 Browser form validation
this.form.setAttribute('novalidate', true);
this.form.addEventListener('submit', e => {
e.preventDefault();
this.handleSubmit();
});
this._addValidationPatterns()
}
/**
* @description handle form validtion
*/
handleSubmit() {
if (this.form.checkValidity()) {
// submit the form if validation is successful
this.submit();
} else {
this.validateForm();
}
}
/**
* @description validate current form
*/
validateForm() {
this.form.classList.add('was-validated');
this.inputs.forEach(el => {
if (!el.validity.valid) {
// handle custom error ....
}
});
}
/**
* @description set the validation pattern for each input of the form
* @private
*/
_addValidationPatterns() {
let pattern;
// add validation patterns from config model
this.inputs.forEach(el => {
if (el.type != 'hidden') {
pattern = this.config.validatorPatterns[el.dataset.pattern || el.type || 'text'];
if (pattern) {
el.setAttribute('pattern', pattern);
}
}
});
}
submit() {
// submit the form :)
this.form.classList.remove('was-validated');
}
}
class FormValidatorModel {
constructor(config = {}) {
/**
* @description possible input types for validation
* @type {*|string} inputTypes
*/
this.inputTypes = config.inputTypes || 'select, textarea, input';
/**
* @description form selector for validation
* @type {*|string} selector
*/
this.selector = config.selector || '';
/**
* @description email validator pattern
* @type {string} email
*/
this.email = '^([a-zA-Z0-9_\\-\\.]+)@([a-zA-Z0-9_\\-\\.]+)\\.([a-zA-Z]{2,5})$';
/**
* @description not only number validator pattern
* @type {string}
*/
this.notOnlyNumbers = '^[0-9]*$';
/**
* @description only numbers validator pattern
* @type {string}
*/
this.onlyNumbers = '[0-9]*';
/**
* @description handles all current active validator patterns
* @type {Object} validatorPatterns
*/
/**
* @description text validator pattern
* @type {string} text
*/
this.text = '';
this.validatorPatterns = {
text: this.text,
email: this.email,
notOnlyNumbers: this.notOnlyNumbers,
numbers: this.onlyNumbers
};
}
}
const validator = new FormValidator({
selector: '#validation-test'
});
Also see: Tab Triggers