php联系表单发送邮件问题

Question

我是php的新手并试图创建一个联系页面，联系页面似乎正在运行但在测试时没有收到邮件，包括以下代码： -

Contact.php

<form id="contactForm" action="contact-send.php" method="POST" novalidate="novalidate">
                            <div class="row">
                                <div class="form-group">
                                    <div class="col-lg-6 ">
                                        <input type="text" id="name" name="name" class="form-control" maxlength="100" data-msg-required="Please enter your name." value="" placeholder="Your Name" >
                                    </div>
                                    <div class="col-lg-6 ">
                                        <input type="email" id="email" name="email" class="form-control" maxlength="100" data-msg-email="Please enter a valid email address." data-msg-required="Please enter your email address." value="" placeholder="Your E-mail" >
                                    </div>
                                </div>
                            </div>
                            <div class="row">
                                <div class="form-group">
                                    <div class="col-md-12">
                                        <input type="text" id="subject" name="subject" class="form-control" maxlength="100" data-msg-required="Please enter the subject." value="" placeholder="Subject">
                                    </div>
                                </div>
                            </div>
                            <div class="row">
                                <div class="form-group">
                                    <div class="col-md-12">
                                        <textarea id="message" class="form-control" name="message" rows="10" cols="50" data-msg-required="Please enter your message." maxlength="5000" placeholder="Message"></textarea>

                                    </div>
                                </div>
                            </div>
                            <div class="row">
                                <div class="col-md-12">
                                    <input type="submit" class="btn btn-default btn-lg" value="Send Message">
                                </div>
                            </div>
                        </form>
                    </div>

接触process.php

<?php

// Email address verification
function isEmail($email) {
    return(preg_match("/^[-_.[:alnum:]]+@((([[:alnum:]]|[[:alnum:]][[:alnum:]-]*[[:alnum:]])\.)+(ad|ae|aero|af|ag|ai|al|am|an|ao|aq|ar|arpa|as|at|au|aw|az|ba|bb|bd|be|bf|bg|bh|bi|biz|bj|bm|bn|bo|br|bs|bt|bv|bw|by|bz|ca|cc|cd|cf|cg|ch|ci|ck|cl|cm|cn|co|com|coop|cr|cs|cu|cv|cx|cy|cz|de|dj|dk|dm|do|dz|ec|edu|ee|eg|eh|er|es|et|eu|fi|fj|fk|fm|fo|fr|ga|gb|gd|ge|gf|gh|gi|gl|gm|gn|gov|gp|gq|gr|gs|gt|gu|gw|gy|hk|hm|hn|hr|ht|hu|id|ie|il|in|info|int|io|iq|ir|is|it|jm|jo|jp|ke|kg|kh|ki|km|kn|kp|kr|kw|ky|kz|la|lb|lc|li|lk|lr|ls|lt|lu|lv|ly|ma|mc|md|mg|mh|mil|mk|ml|mm|mn|mo|mp|mq|mr|ms|mt|mu|museum|mv|mw|mx|my|mz|na|name|nc|ne|net|nf|ng|ni|nl|no|np|nr|nt|nu|nz|om|org|pa|pe|pf|pg|ph|pk|pl|pm|pn|pr|pro|ps|pt|pw|py|qa|re|ro|ru|rw|sa|sb|sc|sd|se|sg|sh|si|sj|sk|sl|sm|sn|so|sr|st|su|sv|sy|sz|tc|td|tf|tg|th|tj|tk|tm|tn|to|tp|tr|tt|tv|tw|tz|ua|ug|uk|um|us|uy|uz|va|vc|ve|vg|vi|vn|vu|wf|ws|ye|yt|yu|za|zm|zw)$|(([0-9][0-9]?|[0-1][0-9][0-9]|[2][0-4][0-9]|[2][5][0-5])\.){3}([0-9][0-9]?|[0-1][0-9][0-9]|[2][0-4][0-9]|[2][5][0-5]))$/i", $email));
}

if($_POST) {

    // Enter the email where you want to receive the message
    $emailTo = 'info@test.com';

    $clientName = trim($_POST['name']);
    $clientEmail = trim($_POST['email']);
    $subject = trim($_POST['subject']);
    $message = trim($_POST['message']);

    $array = array();
    $array['nameMessage'] = '';
    $array['emailMessage'] = '';
    $array['messageMessage'] = '';

    if($clientName == '') {
        $array['nameMessage'] = 'Please enter your name.';
    }
    if(!isEmail($clientEmail)) {
        $array['emailMessage'] = 'Please insert a valid email address.';
    }
    if($message == '') {
        $array['messageMessage'] = 'Please enter your message.';
    }
    if($clientName != '' && isEmail($clientEmail) && $message != '') {
        // Send email
    $headers = "From: " . $clientName . " <" . $clientEmail . ">" . "\r\n" . "Reply-To: " . $clientEmail;
    mail($emailTo, $subject, $message, $headers);
    }

                        $url = 'index.php?page=process&msg=7';
                        echo "<script language=\"javascript\">
                        location.href=\"$url\";
                        </script>";
                        exit; 

}

?>

我遇到的问题是，在填写表单后，它会重定向到成功页面，但我没有收到电子邮件。