How to submit form with validation in javascript and php?
How to submit form with validation in javascript and php?
1 answer
by
edmond_brakus ,
2 years ago
@hal.littel
To submit a form with validation using JavaScript and PHP, you can follow these steps:
JavaScript:
- First, write a JavaScript function that will be called when the form is submitting.
- Inside this function, prevent the default form submission using event.preventDefault().
- Perform your form validation checks such as validating required fields, checking email format, etc.
- If any validation fails, display error messages to the user.
- If all validation passes, use the fetch() or XMLHttpRequest API to send a POST request to the PHP server.
Here's a sample code for the JavaScript part:
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document.getElementById('your-form-id').addEventListener('submit', function(event) {
event.preventDefault(); // prevent form submission
// Perform form validation
var form = event.target;
// example: checking if a required field is empty
if (form.yourField.value.trim() === '') {
alert('Please fill in the required fields');
return;
}
// If validation passes, send the form data to PHP
var formData = new FormData(form);
fetch('your-php-file.php', {
method: 'POST',
body: formData
})
.then(function(response) {
return response.text();
})
.then(function(data) {
// Optionally, do something with the response from PHP
console.log(data);
// Redirect or show success message to the user
})
.catch(function(error) {
console.error('Error:', error);
});
});
|
PHP:
- Create a PHP file that will receive the form data and perform server-side validation checks.
- Retrieve the form data using $_POST superglobal.
- Perform the necessary validation checks, like validating email format, checking the presence of required fields, etc.
- If any validation fails, send an appropriate error response back to the JavaScript code.
- If all validation passes, process the form data as needed and send a response back to the JavaScript code.
Here's a sample code for the PHP part:
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<?php
// Perform server-side validation
if ($_SERVER['REQUEST_METHOD'] === 'POST') {
$yourField = $_POST['yourField'];
// Example server-side validation - checking if a field is empty
if (empty($yourField)) {
// Send an error response back to JavaScript
http_response_code(400); // Example error HTTP status code
echo 'YourField is a required field';
exit();
}
// If validation passes, process the form data and send a success response
// ...
echo 'Form submitted successfully';
}
?>
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Make sure to adapt the JavaScript code by replacing your-form-id and your-php-file.php with your form's HTML id attribute and the PHP file you've created to handle form submission, respectively.
Remember to enhance the server-side validation according to your specific requirements.