Custom plugin for file upload and view

file_upload.php

<?php
/*
Plugin Name: CV
Plugin URI: http://Gowebbi.com/
Description: CV
Author:
Version: 1.0
Author URI: http://Gowebbi.com/
*/
add_action('admin_menu', 'wp_show_summery');
// action function for above hook
function wp_show_summery()
{
    add_menu_page(__('CV', 'menu-task'), __('CV', 'menu-task'), 'edit_pages', 'wp_docs', 'wp_docs');
    add_submenu_page('wp_docs', __('View Uploads', 'menu-task'), __('View Uploads', 'menu-task'), 'edit_pages', 'view_uploads', 'view_uploads');
}

function wp_docs(){ ?>
        <div class="wrap">
        <div style="" id="new-file-uploader">
            <div id="poststuff">
                <div id="post-body" class="metabox-holder" style="width:520px">
                    <div id="post-body-content">
                        <div id="namediv" class="stuffbox">
                            <h3>Add new Excel File</h3>

                            <div class="inside">
                                <form method="post" enctype="multipart/form-data">
                                    <table class="form-table" style="width:500px">
                                        <tr>
                                            <td>Name:</td>
                                            <td><input type="text" name="file_name"
                                                       placeholder="Give it a name (required)" required/></td>
                                        </tr>
                                        <tr>
                                            <td>File:</td>
                                            <td><input type="file" name="file" style="width:400px" required/>Only *.xlsx
                                                Filetypes are supported
                                            </td>
                                        </tr>
                                        <tr>
                                            <td>Upload:</td>
                                            <td><input type="submit" class="button-primary" name="upload"
                                                       value="Start upload"/></td>
                                        </tr>
                                    </table>
                                </form>
                            </div>
                        </div>
                    </div>
                </div>
            </div>
        </div>
        <?php
        if (isset($_POST['upload'])) {
        $extension = end(explode(".", $_FILES["file"]["name"]));
        $fileSize = $_FILES["file"]["size"];
        if ($_FILES["file"]["size"] < 200000000000000000) {
            if (!function_exists('wp_handle_upload')) {
                require_once(ABSPATH . 'wp-admin/includes/file.php');
            }
            $uploadedfile = $_FILES['file'];
            $upload_overrides = array('test_form' => false);
            $movefile = wp_handle_upload($uploadedfile, $upload_overrides);
            if ($movefile && !isset($movefile['error'])) {
                echo "File is valid, and was successfully uploaded.\n";
                global $wpdb;
                $id = get_current_user_id();
                $fileName = $_POST['file_name'];
                $fileUrl = $movefile['url'];
                $wpdb->insert(
                    'soc_dev_excel',
                    array(
                        'user_id' => $id,
                        'sheet_name' => $fileName,
                        'sheet_url' => $fileUrl,
                        'file_size' => $fileSize
                    ),
                    array(
                        '%s',
                        '%s',
                        '%s',
                        '%s'
                    )
                );
            } else {
                /**
                 * Error generated by _wp_handle_upload()
                 * @see _wp_handle_upload() in wp-admin/includes/file.php
                 */
                echo $movefile['error'];
            }
        } else {
            echo "Invalid file";
        }
    }
    ?>
</div>
<?php }
add_shortcode('my_short_code', 'wp_docs');





function view_uploads()
{ ?>
    <style>tr:nth-child(even) {background: #B8D1F3}
        tr:nth-child(odd) {background: #DAE5F4}
        th { background-color:#0A819C; color:black; text-align:center; height:30px; }
        table,th,td { border:1px solid green;}
        table { width:30%; color:black; text-align:center; }
    </style>
    <div style="margin-top:30px;width:75%">
        <form method="post" action="">
            <table class="widefat">
                <thead>
<!--                <tr>-->
                    <th style="text-align: center; font-weight: bold;">Sl No.</th>
                    <th style="text-align: center;font-weight: bold;">Name</th>
                    <th style="text-align: center;font-weight: bold;">File Size</th>
                    <th style="text-align: center;font-weight: bold;">Edit</th>
                    <th style="text-align: center;font-weight: bold;">Action</th>
<!--                </tr>-->
                </thead>
                <tbody>
                <?php
                $currentUser = get_current_user_id();
                global $wpdb;
                if ($currentUser == 1) {
                    $results = $wpdb->get_results("select id,sheet_name,user_id,sheet_url,file_size
                             from soc_dev_excel ");
                } else {

                    $sql = "SELECT * from soc_dev_excel where user_id=$currentUser";
                    $results = $wpdb->get_results($sql);
                }
                foreach ($results as $result) {
                    ?>

                    <tr>
                        <td><?php echo $result->id ?></td>
                        <td class="row-title">
                            <a href=""></a>
                            <div id="uploader-"><?php echo $result->sheet_name ?> </div>
                        </td>
                        <td><?php echo $result->file_size ?> kb</td>
                        <td style="text-align: center;"><a href="<?php echo $result->sheet_url ?> ">Download</a></td>
                        <td style="text-align: center; ">
                            <input type="hidden" name="doc_id" value="<?php echo $result->id;?>">
                            <input type="submit" name="deleteItem" value="Delete" style="cursor:pointer" />
<!--                            <a href="--><?php //echo site_url() ?><!--/admin.php?page=view_uploads?id=--><?php //echo $result->id ?><!-- " style="color: red"> Delete </a>-->
                        </td>
                    </tr>
                <?php
                    if(isset($_POST['deleteItem'])){
                        global $wpdb;
                        $item = $_POST['doc_id'];
                        $wpdb->delete( 'soc_dev_excel', array( 'id' => $item ) );
                    }
                } ?>
                </tbody>
            </table>
        </form>
    </div>
<?php }
?>

If you need only the form in the front- end then cut the form and paste it the front-end and keep the form processing code inside the wp_docs() function and call the function by adding this add_action( 'template_redirect', 'wp_docs' ); in the functions.php. It will automatically process your form while submitting the form from the front end.

nice....clean code

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