echo和谷歌跟踪代码

我有一个简单的php联系我们脚本，通过echo命令在同一页面上显示"谢谢"。一切都很好，但我的问题是，如果我在echo部分中包含Google GA跟踪代码，跟踪代码是在页面加载期间触发的，还是只有在实际调用echo时才触发？这有道理吗？（我正在努力跟踪转换情况——有多少人通过网站发送了电子邮件）

我的网站是bplegal.com/demo/contact_us.php。以下是php代码：

    <style>
.error_message {padding:3px;
font-family:font-family: ‘Arial Narrow’, sans-serif;
font-size:11px;
color:#a0c33f;
text-transform:uppercase;}
</style>
<?php
if(!$_POST) exit;
// Email address verification, do not edit.
function isEmail($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|me|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 (!defined("PHP_EOL")) define("PHP_EOL", "'r'n");
$name     = $_POST['name'];
$email    = $_POST['email'];
$phone   = $_POST['phone'];
$subject  = $_POST['subject'];
$comments = $_POST['comments'];
$verify   = $_POST['verify'];
if(trim($name) == '') {
    echo '<div class="error_message"><b>Attention!</b> You must enter your name.</div>';
    exit();
} else if(trim($email) == '') {
    echo '<div class="error_message"><b>Attention!</b> Please enter a valid email address.</div>';
    exit();
} else if(trim($phone) == '') {
    echo '<div class="error_message"><b>Attention!</b> Please enter a valid phone number.</div>';
    exit();
} else if(!is_numeric($phone)) {
    echo '<div class="error_message"><b>Attention!</b> Phone number can only contain digits.</div>';
    exit();
} else if(!isEmail($email)) {
    echo '<div class="error_message"><b>Attention!</b> You have enter an invalid e-mail address, try again.</div>';
    exit();
} else if(trim($comments) == '') {
    echo '<div class="error_message"><b>Attention!</b> Please enter your message.</div>';
    exit();
} else if(!isset($verify) || trim($verify) == '') {
    echo '<div class="error_message"><b>Attention!</b> Please enter the verification number.</div>';
    exit();
} else if(trim($verify) != '4') {
    echo '<div class="error_message"><b>Attention!</b> The verification number you entered is incorrect.</div>';
    exit();
}
if(get_magic_quotes_gpc()) {
    $comments = stripslashes($comments);
}

$address = "info@jbplegal.com";


$e_subject = 'You''ve been contacted by ' . $name . '.';


$e_body = "You have been contacted by $name with regards to" . PHP_EOL . PHP_EOL;
$e_content = "'"$comments'"" . PHP_EOL . PHP_EOL;
$e_reply = "You can contact $name via email, $email or via phone $phone";
$msg = wordwrap( $e_body . $e_content . $e_reply, 70 );
$headers = "From: $email" . PHP_EOL;
$headers .= "Reply-To: $email" . PHP_EOL;
$headers .= "MIME-Version: 1.0" . PHP_EOL;
$headers .= "Content-type: text/plain; charset=utf-8" . PHP_EOL;
$headers .= "Content-Transfer-Encoding: quoted-printable" . PHP_EOL;
if(mail($address, $e_subject, $msg, $headers)) {
    // Email has sent successfully, echo a success page.
    echo "<fieldset>";
    echo "<div id='success_page'>";
    echo "Email Sent Successfully.";
    echo "<p>Thank you <strong>$name</strong>, your message has been submitted to us.</p>";
     ?>
    <img height="1" width="1" style="border-style:none;" src="//tracking-code"/>
    <script>
(function(i,s,o,g,r,a,m){i['GoogleAnalyticsObject']=r;i[r]=i[r]||function(){
(i[r].q=i[r].q||[]).push(arguments)},i[r].l=1*new Date();a=s.createElement(o),
m=s.getElementsByTagName(o)[0];a.async=1;a.src=g;m.parentNode.insertBefore(a,m)
})(window,document,'script','//www.google-analytics.com/analytics.js','ga');
ga('create', 'UA-XXXXXXX', 'auto');
ga('send', 'pageview');
    </script>
<?php
    echo "</div>";
    echo "</fieldset>";
} else {
    echo 'ERROR!';
}