email.php

<?php
function test_input($data) {
    $data = trim($data);
    $data = stripslashes($data);
    $data = htmlspecialchars($data);
    return $data;
}

if ($_SERVER["REQUEST_METHOD"] == "POST") {
	
// define variables and set to empty values
$fnameErr = $lnameErr = $emailErr = "";
$fname = $lname = $msg = $email = "";


    if (empty($_POST["inputFirstName"])) {
        $fnameErr = "* First name is required";
    } else {
    $fname = test_input($_POST["inputFirstName"]);
    // check if name only contains letters and whitespace
    if (!preg_match("/^[a-zA-Z ]*$/",$fname)) {
        $fnameErr = "* Only letters and white space allowed"; 
		}
    }

	if (empty($_POST["inputLastName"])) {
		$lnameErr = "* Last name is required";
	} else {
		$lname = test_input($_POST["inputLastName"]);
		// check if name only contains letters and whitespace
		if (!preg_match("/^[a-zA-Z ]*$/",$lname)) {
			$lnameErr = "* Only letters and white space allowed"; 
		}
	}

    if (empty($_POST["inputEmail"])) {
		$emailErr = "* Email is required";
    } else {
		$email = test_input($_POST["inputEmail"]);
		// check if e-mail address is well-formed
		if (!filter_var($email, FILTER_VALIDATE_EMAIL)) {
			$emailErr = "* Invalid email format"; 
		}
	}

	if (empty($_POST["inputContact"])) {
		$msg = "";
	} else {
		$msg = test_input($_POST["inputContact"]);
	}
  
	if (empty($fnameErr) and empty($lnameErr) and empty($emailErr)) {
		$msg = "Mail from: " . $fname . " " . $lname . " at " . $email . ".\n\n" . $msg;
		mail("cs.sculley@gmail.com","NEGITOROMAKI",$msg);
		echo "Mail sent, thanks " . $fname . "!";
	} else {
		echo "Mail not sent, please check over these error messages!";
		echo "\n" . $fnameErr . "\n" . $lnameErr . "\n" . $emailErr;
	}
}
?>