用getenv函數獲取各種CGI環境變量

<?php
$array = array(
                "REMOTE_ADDR",
                "DOCUMENT_ROOT",
                "GATEWAY_INTERFACE",
                "SERVER_SOFTWARE",
                "SERVER_NAME",
                "SERVER_PROTOCOL",
                "SERVER_PORT",
                "SERVER_ADMIN",
                "SERVER_SIGNATURE",
                "REQUEST_METHOD",
                "REQUEST_URI",
                "PATH_INFO",
                "PATH_TRANSLATED",
                "SCRIPT_NAME",
                "SCRIPT_FILENAME",
                "QUERY_STRING",
                "REMOTE_HOST",
                "REMOTE_ADDR",
                "REMOTE_USER",
                "REMOTE_IDENT",
                "CONTENT_TYPE",
                "CONTENT_LENGTH",
                "HTTP_ACCEPT",
                "HTTP_ACCEPT_CHARSET",
                "HTTP_ACCEPT_LANGUAGE",
                "HTTP_ENCODING",
                "HTTP_USER_AGENT",
                "HTTP_CONNECTION",
                "HTTP_HOST",
                "HTTP_REFERER",
                "AUTH_TYPE"
               );

echo '<center>';
echo '<table border="1" cellspacing="0" cellpadding="0">';
echo '<caption>CGI Environment Variables</caption>';
echo '<tr><th>Name<th>Value</tr>';

$count = count($array);
for($i=0;$i<$count;$i++){
    $value = getenv($array[$i]);
    if($value){
       echo "<tr><td>$array[$i]<td>" . $value . "</tr>";
    }
//下面的語句也可以哦
//    if(isset($$array[$i])){
//       echo "<tr><td>$array[$i]<td>" . $$array[$i] . "</tr>";
//    }
}

echo '</table&g>';

?>