Php 在两个下拉菜单之间进行验证，以便只能选择一个

我有一个脚本，用户在它下面记录一个php表单

有两个下拉菜单相邻的部分，“npc\u电池\u n\u代码”和“npc\u电池\u其他\u代码”

我正在尝试做的是使其中一个下拉菜单必须为要提交的表单选择一个选项，但不能同时选择这两个选项或不选择任何选项

因此，例如，如果在“npc_battery_n_code”中选择一个选项，然后用户在“npc_battery_other_code”中选择另一个选项，则“npc_battery_n_code”的值将恢复为“None”选项

欢迎提出任何建议

     <?php //logsale.php
     require_once ('./includes/config.inc.php');
     $page_title = 'Log a sale';
     include ('./includes/header.html');

     if (!isset($_SESSION['sp_user_id'])) {

     $url = 'http://' . $_SERVER['HTTP_HOST']
     . dirname($_SERVER['PHP_SELF']);
     // Check for a trailing slash.
     if ((substr($url, -1) == '/') OR (substr($url, -1) == '\\') ) {
     $url = substr ($url, 0, -1); // Chop off the slash.
     }
     $url .= '/login.php'; 

     ob_end_clean(); // Delete the buffer.
     header("Location: $url"); 
     exit(); // Quit the script.
     }
     $users = $_SESSION['sp_user_id'];
     ?>

     <h1>Heading</h1>

     <?php

     if (isset($_POST['submitted'])) {// Handle the form.

     require_once ('mydatabase.php');

     if (!empty($_POST['npc_quantity'])) {
     $quantity = escape_data($_POST ['npc_quantity']);
     } else {
     $quantity = FALSE;
     echo '<p><font color="red">You forgot to enter the Quantity</font></p>';
     }  

     if (!empty($_POST['npc_customer_name'])) {
     $customer = escape_data($_POST ['npc_customer_name']);
     } else {
     $customer = FALSE;
     echo '<p><font color="red">You forgot to enter the Customer Name</font></p>';
     }  

     if (!empty($_POST['npc_registration_no'])) {
     $rego = escape_data($_POST ['npc_registration_no']);
     } else {
     $rego = FALSE;
     echo '<p><font color="red">You forgot to enter the Customer Rego Number</font></p>';
     }  

     if (!empty($_POST['npc_suo_no'])) {
     $suo = escape_data($_POST ['npc_suo_no']);
     } else {
     $suo = FALSE;
     echo '<p><font color="red">You forgot to enter the SUO Number</font></p>';
     }  

     if (!empty($_POST['npc_amb_club_no'])) {
     $repair_order = escape_data($_POST ['npc_amb_club_no']);
     } else {
     $repair_order = FALSE;
     echo '<p><font color="red">You forgot to enter the A-Club number</font></p>';
     }  

     if (!empty($_POST['npc_repair_order'])) {
     $amb_club = escape_data($_POST ['npc_repair_order']);
     } else {
     $amb_club = FALSE;
     echo '<p><font color="red">You forgot to enter the Repair Order</font></p>';
     }  

     if (!empty($_POST['npc_invoice_no'])) {
     $inv = escape_data($_POST ['npc_invoice_no']);
     } else {
     $inv = FALSE;
     echo '<p><font color="red">You forgot to enter the Invoice Number </font></p>';
     }  

     if (!empty($_POST['npc_entry_userdate'])) {
     $inv_date = escape_data($_POST ['npc_entry_userdate']);
     } else {
     $inv_date = FALSE;
     echo '<p><font color="red">You forgot to enter the Invoice Date</font></p>';
     }

     if ($quantity && $customer && $rego && $suo && $repair_order && $amb_club && $inv && $inv_date)  {

     $uid = @mysql_insert_id(); //Get the url ID.
     $query = "INSERT INTO npc_sales_list 
     (npc_item_id , sp_user_id, npc_battery_n_code, npc_battery_other_code, npc_quantity, 
     npc_customer_name, npc_registration_no, npc_suo_no, npc_amb_club_no, npc_repair_order,
     npc_entry_userdate, npc_usertype, npc_points, npc_bonus_points, npc_entry_date)
     VALUES
     ('$uid', '$users', '$_POST[npc_battery_n_code]', '$_POST[npc_battery_other_code]', '$quantity',
     $customer , $rego, $suo, $amb_club , $repair_order, 
     $inv , 'NPC', '5' , '0' , NOW())";
     $result = mysql_query ($query) or trigger_error
     ("Query: $query\n<br />MySQL Error: " .mysql_error());

     if ($result = @mysql_query($query)) {

     //Finish the page.
     echo '<p>The sale with invoice number: <strong>' . $inv . '</strong>       <br />
     is now registered into the system.</p>
     <p>If you would like to log in further sales, please <a href="logsale.php">click here</a></p>
     <p>If you would like to view your sales log, please <a href="viewsales.php">click here</a></p>
     ';
     include ('./includes/footer.html'); // Include the HTML footer.
     exit();

     } else { // If it did not run OK.
     echo '<p><font color="red" size="+1">You could not be
     registered due to a system error. We apologize for any
     inconvenience.</font></p>';
     }

     } 

     } else { // If one of the data tests failed.
     echo '<p><font color="red" size="+1">Please check all manatory fields are complete and try again.
     </font></p>';
     }

     mysql_close(); // Close the database connection.

     ?>                         


     <form enctype="multipart/form-data" action="logsale.php" method="post">


     <table width="520" border="0" cellspacing="3" cellpadding="2">

     <tr>
     <td width="184"><div align="right">NPC Vehicle<span class="style2">*</span></div></td>
     <td width="323"><select  name="npc_battery_n_code" id="npc_battery_n_code">
     <option value="None" 
     <?php if (isset($_POST['npc_battery_n_code']) && $_POST['npc_battery_n_code'] == 'None') 
     {echo 'selected="selected"';} ?>>None
     </option>
     <option value="55D23L" 
     <?php if (isset($_POST['npc_battery_n_code']) && $_POST['npc_battery_n_code'] == '55D23L') 
     {echo 'selected="selected"';} ?>>55D23L
     </option>
     <option value="55D23R" 
     <?php if (isset($_POST['npc_battery_n_code']) && $_POST['npc_battery_n_code'] == '55D23R') 
     {echo 'selected="selected"';} ?>>55D23R
     </option>                                
     <option value="75D23R" 
     <?php if (isset($_POST['npc_battery_n_code']) && $_POST['npc_battery_n_code'] == '75D23R') 
     {echo 'selected="selected"';} ?>>75D23R
     </option>
     </select></td>
     </tr>

     <tr>
     <td width="184"><div align="right">Other <span class="style2">*</span></div></td>
     <td width="323">
     <select  name="npc_battery_other_code" id="npc_battery_other_code">
     <option value="50D20L" 
     <?php if (isset($_POST['npc_battery_other_code']) && $_POST['npc_battery_other_code'] == '50D20L') 
     {echo 'selected="selected"';} ?>>50D20L
     </option>
     <option value="50D20R" 
     <?php if (isset($_POST['npc_battery_other_code']) && $_POST['npc_battery_other_code'] == '50D20R') 
     {echo 'selected="selected"';} ?>>50D20R
     </option>
     <option value="55D23LMF" 
     <?php if (isset($_POST['npc_battery_other_code']) && $_POST['npc_battery_other_code'] == '55D23LMF') 
     {echo 'selected="selected"';} ?>>55D23LMF
     </option>
     <option value="55D23RMF" 
     <?php if (isset($_POST['npc_battery_other_code']) && $_POST['npc_battery_other_code'] == '55D23RMF') 
     {echo 'selected="selected"';} ?>>55D23RMF
     </option>
     </select></td>
     </tr>

     <tr>
     <td><div align="right">Quantity <span class="style2">*</span></div></td>
     <td><input type="text" name="npc_quantity" size="10" maxlength="10" 
     value="<?php if (isset($_POST['npc_quantity'])) echo $_POST['npc_quantity']; ?>" /></td>
     </tr>

     <tr>
     <td><div align="right">Customer name<span class="style2">*</span></div></td>
     <td><input type="text"  name="npc_customer_name" size="30" maxlength="30" 
     value="<?php if (isset($_POST['npc_customer_name'])) echo $_POST['npc_customer_name']; ?>" /></td>
     </tr>

     <tr>
     <td><div align="right">Rego number <span class="style2">*</span></div></td>
     <td><input type="text" name="npc_registration_no" size="10" maxlength="7" 
     value="<?php if (isset($_POST['npc_registration_no'])) echo $_POST['npc_registration_no']; ?>" /></td>
     </tr>

     <tr>
     <td><div align="right">SUO No.<span class="style2">*</span></div></td>
     <td><input type="text" name="npc_suo_no" size="10" maxlength="7" 
     value="<?php if (isset($_POST['npc_suo_no'])) echo $_POST['npc_suo_no']; ?>"/></td>
     </tr>

     <tr>
     <td><div align="right">A-Club ID<span class="style2">*</span></div></td>
     <td><input type="text" name="npc_amb_club_no" size="15" maxlength="7" 
     value="<?php if (isset($_POST['npc_amb_club_no'])) echo $_POST['npc_amb_club_no']; ?>"/></td>
     </tr>

     <tr>
     <td><div align="right">Repair Order <span class="style2">*</span></div></td>
     <td><input type="text" name="npc_repair_order" size="15" maxlength="12" 
     value="<?php if (isset($_POST['npc_repair_order'])) echo $_POST['npc_repair_order']; ?>" /></td>
     </tr>

     <tr>
     <td><div align="right">Invoice No. <span class="style2">*</span></div></td>
     <td><input size="10" name="npc_invoice_no" 
     value="<?php if (isset($_POST['npc_invoice_no'])) echo $_POST['npc_invoice_no']; ?>" /></td>
     </tr>

     <tr>
     <td><div align="right">Invoice Date <span class="style2">*</span></div></td>
     <td><input size="12" name="npc_entry_userdate" maxlength="10" 
     value="<?php if (isset($_POST['npc_entry_userdate'])) echo $_POST['npc_entry_userdate']; ?>"/>  </td>
     </tr>

     <tr>
     <td></td>
     <td><input type="submit" name="submit" value="Submit" /></p><input type="hidden" name="submitted" value="TRUE" />
     &nbsp;</td>
     </tr>
     </table>
     </form>

     <p>Footer</p>


     <?php
     include ('./includes/footer.html');
     ?> 

就是您要找的

PHP或Mysql无法实现脚本的工作方式。您只能在加载网站时处理数据。如果您想在不刷新页面的情况下编辑数据，则需要使用JavaScript或更高级的jQuery。
谢谢#Leon Kramer，这正是我想要的！