Form Validate Email :A valid email must contain @ and . symbols. PHP provides various methods to validate the email address. Here, we will use regular expressions to validate the email address.
Form Validate URL :The below code validates the URL of website provided by the user via HTML form. If the field does not contain a valid URL, the code will display an error message, i.e., "URL is not valid".
Example of validate Email and URL :
<html>
<body>
<?php
$emailErr=$urlErr = "";
$email = $url = "";
if ($_SERVER["REQUEST_METHOD"] == "POST") {
if (empty($_POST["email"])) {
$emailErr = "Email is required";
} else {
$email = test_input($_POST["email"]);
// check if e-mail address is well-formed
if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
$emailErr = "Invalid email format";
}
}
if (empty($_POST["url"])) {
$url = "";
} else {
$url = test_input($_POST["url"]);
// check if URL address syntax is valid
if (!preg_match("/\b(?:(?:https?|ftp):\/\/|www\.)[-a-z0- 9+&@#\/%?=~_|!:,.;]*[-a-z0-9+&@#\/%=~_|]/i",$url)) {
$urlErr = "Invalid URL";
}
}
}
function test_input($data) {
$data = trim($data);
$data = stripslashes($data);
$data = htmlspecialchars($data);
return $data;
}
?>
<h2>Form URL/Email</h2>
<p><span class="error">* required field</span></p>
<form method="post" action="<?php echo htmlspecialchars($_SERVER["PHP_SELF"]);?>">
Email : <input type="text" name="email">
<span class="error">* <?php echo $emailErr;?></span><br><br>
URl :<input type="text" name="url">
<span class="error"><?php echo $urlErr;?></span><br>
<input type="submit" name="submit" value="Submit">
</form>
<?php
echo "<h2>Your Input:</h2>";
echo $email;
echo "<br>";
echo $url;
echo "<br>";
?>
</body>
</html>
Output : invalid Email/URL
Valid Email/URL :