使用PHP连接HTML的良好编程实践

<?php include("header.php"); ?>


<div id="main">
    <table id="mainTable">
        <tr>
            <td id="leftPane">
                <div class="pgbody">

                    <div class="subblock">
                        <form action="<?php echo htmlentities($_SERVER['PHP_SELF']); ?>" method="post">
                        <table width="100%" cellpadding="10" cellspacing="0">
                                <tr>
                                    <td colspan="3" style="width:99%">
                                    <label for="isVersion">InstallShield Version</label><br />
                                    <select name="isVersion" onchange="javascript:setTimeout('__doPostBack('ddlVersion','')',0)" id="isVersion" class="box">
                                        <option value="2012Spring">2012 Spring</option>
                                        <option value="2012">2012</option>
                                        <option value="2011">2011</option>
                                        <option value="2010">2010</option>
                                        <option value="2009">2009</option>
                                        <option value="2009 Express">2009 Express</option>
                                        <option value="IS2008">2008</option>
                                        <option value="IS2008 Express">2008 Express</option>
                                    </select>

                                    <tr>
                                        <td colspan="3" style="width:99%">
                                            <br />
                                            <input type="checkbox" name="no_internet" value="no_internet"> no_internet
                                        </td>
                                    </tr>

                                    <tr>
                                        <td colspan="3" style="width:99%">
                                        <br />
                                        <input type="submit" name="submit" value="Submit">
                                        </td>
                                    </tr>
                                </tr></table>
                        <?php

                        if(isset($_POST['submit']))
                        {
                            echo "<h2>Response</h2><br />";
                            $isVersion = $_POST["isVersion"];
                            $output_script = "
                                    <p>Hello,<br />
                                    To activate InstallShield,please follow the steps below:<br /><br />

                                    1. Launch a Command Prompt window and browse to the directory - 'C:Program FilesInstallShield$isVersionSystem' (or 'Program Files (x86)' on a 64 bit machine)<br />
                                    2. You will need to pass the parameter '/return' to the executable 'TSconfig' as below<br />
                                    'C:Program FilesInstallShield$isVersionSystemTSconfig.exe /return'<br />
                                    3. Providing the machine has a valid internet connection the license will deactivate and the message in the dialog will reflect this<br />
                                    4. Re-launch InstallShield.exe and you will be presented with the same activation dialog as before<br />
                                    5. Proceed with the activation normally<br />
                                    6. The dialog should show a successful activation message and the product should remain activated at this stage.<br />
                                     </p>";
                        ?>

                        <div class="ResponseBox" style="background-position: 0 0;">
                            <div class="ResponseText">
                                <?php echo $output_script;
                        }
                                 ?>
                        <?php
                        elseif(isset($_POST['submit']) && $_POST['no_internet'])
                        {
                            echo "<h2>Response</h2><br />";
                            $isVersion = $_POST["isVersion"];
                            $no_internet = $_POST["no_internet"];
                            $output_script = "
                                    <p>Hello,please follow the steps below:<br /><br />

                                    1. Launch a Command Prompt window and browse to the directory - 'C:Program FilesInstallShield$isVersionSystem' (or 'Program Files (x86)' on a 64 bit machine)<br />
                                    2. You will need to pass the parameter '/return' to the executable 'TSconfig' as below<br />
                                    'C:Program FilesInstallShield$isVersionSystemTSconfig.exe /return /$no_internet'<br />
                                    3. Providing the machine has a valid internet connection the license will deactivate and the message in the dialog will reflect this<br />
                                    4. Re-launch InstallShield.exe and you will be presented with the same activation dialog as before<br />
                                    5. Proceed with the activation normally<br />
                                    6. The dialog should show a successful activation message and the product should remain activated at this stage.<br />
                                     </p>";
                        ?>
                        <div class="ResponseBox" style="background-position: 0 0;">
                            <div class="ResponseText">
                                <?php echo $output_script;
                        }
                                 ?>
                            </div>
                        </div>    
                    </div>
            </td>

            <td id="rightPane">
                <div class="PromoBox" style="background-position: 0 0;">
                    <div class="PromoText">
                            <?php
                            echo "<h2>Related KB Article: </h2><br />";
                            echo "<h3>Deactivation of IS - Q201081</h3>";
                            ?>
                    </div>
                </div>
            </td>
                                </tr>
        </tr>
    </table>
</div>

正如您所看到的,PHP和HTML在需要时会相互连接.我想知道,但是,如果这实际上是最好的方法,我应该使用PHP回应所有内容,而不是像上面那样做？
我也试图在这下面写一个elseif块,它给了我一个错误,说明elseif是意外的,这就是让我觉得我接近这一切都错了.

当我看到人们制作的大型项目时,我注意到每个文件中几乎没有任何东西,而且肯定不会有很多HTML可见.假设大多数都在对象或类中,我是否正确？任何建议或参考将不胜感激.提前致谢.