致命错误：调用未定义的函数get\\u header（）

我不能让它工作。我使用wordpress附带的213个默认主题。我创建了一个名为table.php 我还使用了<?php template name ?>. 这个自定义模板只显示数据库中的所有记录。它工作正常，但缺少页眉和页脚，当我试图通过添加get_header 和get_footer, 它抛出一个致命错误。代码如下：

我要说的是，我曾经index.php 它位于Twenty13文件夹中，而不是根文件夹中wp-config 文件或任何其他index.php 就这点而言。

<?php
/**
 * The main template file
 *
 * This is the most generic template file in a WordPress theme and one of the
 * two required files for a theme (the other being style.css).
 * It is used to display a page when nothing more specific matches a query.
 * For example, it puts together the home page when no home.php file exists.
 *
 * @link http://codex.wordpress.org/Template_Hierarchy
 *
 * @package WordPress
 * @subpackage Twenty_Thirteen
 * @since Twenty Thirteen 1.0
 */

get_header(); ?>



<DIV class="form">

        <form method = "post"  action="<?php echo get_stylesheet_directory_uri(); ?>/dbentry.php">
            First Name: <input type="text" name = "first">*<?php echo $first_error;?><br>

            Last Name: <input type="text" name = "last">*<?php echo $last_error; ?><br>

            Email: &nbsp &nbsp &nbsp &nbsp    <input type="text" name = "email"><br>
            Telephone: <input type="number" name = "telephone">*<?php echo $tele_error; ?><br>

            Gender:&nbsp &nbsp 
            <input type="radio" name = "gender" value = "female">Female
            <input type="radio" name = "gender" value = "male">Male
            <br>

            <input type="submit" value ="submit" name="submit"><br>


        </form>
 </DIV>    

        <form action="<?php echo get_stylesheet_directory_uri(); ?>/tab.php"     method="post">
            <input type="submit" name = \'submit2\' value = \'http://localhost/wordpress/?page_id=11\'>
        </form>

<?php get_sidebar(); ?>
<?php get_footer(); ?>

Here is the code where the call will go after pressing the "Show all records" button.

<?php
    /**
     * The template for displaying all pages
     *
     * This is the template that displays all pages by default.
     * Please note that this is the WordPress construct of pages and that other
     * \'pages\' on your WordPress site will use a different template.
     *
     * @package WordPress
     * @subpackage Twenty_Thirteen
     * @since Twenty Thirteen 1.0
     */

     /* 
     Template name: tab
     */

    get_header(); ?>

    <div class="table">
        <table class = "border">
            <?php

               require "db.php";

               if(isset($_POST[\'submit2\'])){
                    $query = "SELECT * FROM person";
                    $result = mysqli_query($connection, $query);
                    $row = \'\';
                    $id = "";
                    echo "<tr>";
                    echo "<th><b>ID</b></th>";
                    echo "<th><b>FIRST</b></th>";
                    echo "<th><b>LAST</b></th>";
                    echo "<th><b>EMAIL</b></th>";
                    echo "<th><b>TELEPHONE</b></th>";
                    echo "<th><b>GENDER</b></th>";
                    echo "<th  scope=\'row\'>EDIT</th>";
                    echo "<th>DELETE</th>";
                    echo "</tr>";
            echo "<tr>this is working just fine</tr>";
                    while($row = mysqli_fetch_array($result)){
                        $id = $row[\'ID\'];
            echo $id ;

                        echo "<tr><td>".$row[\'ID\']."</td><td>".$row[\'First\']."</td><td>".$row[\'Last\']."</td><td>".$row[\'Email\']."</td><td>".$row[\'Telephone\'].
                        "</td><td>".$row[\'Gender\']."</td><td>"."<a href=\'edit.php?ID=$id\'><input type=\'button\' class = \'edit\' value = \'Edit\'></a>"."</td><td>"."<a href=\'delete.php?ID=$id\'><input type=\'button\' class = \'del\' value=\'Delete\'></a>"."</td></tr>";

                    }

                    mysqli_close($connection);

               } 
            ?>
        </table>
    </div>

    <table>
        <tr>jsdnsdjnsjd</tr>
    </table>



        <form action="form.php" method="post">
        <input type="submit" name="new" value="New Entry" class = "new">
        </form>




    <?php get_sidebar(); ?>
    <?php get_footer(); ?>