<?php /** * Plugins may load this file to gain access to special helper functions * for plugin installation. This file is not included by WordPress and it is * recommended, to prevent fatal errors, that this file is included using * require_once. * * These functions are not optimized for speed, but they should only be used * once in a while, so speed shouldn't be a concern. If it is and you are * needing to use these functions a lot, you might experience timeouts. * If you do, then it is advised to just write the SQL code yourself. * * check_column( 'wp_links', 'link_description', 'mediumtext' ); * * if ( check_column( $wpdb->comments, 'comment_author', 'tinytext' ) ) { * echo "ok\n"; * } * * // Check the column. * if ( ! check_column( $wpdb->links, 'link_description', 'varchar( 255 )' ) ) { * $ddl = "ALTER TABLE $wpdb->links MODIFY COLUMN link_description varchar(255) NOT NULL DEFAULT '' "; * $q = $wpdb->query( $ddl ); * } * * $error_count = 0; * $tablename = $wpdb->links; * * if ( check_column( $wpdb->links, 'link_description', 'varchar( 255 )' ) ) { * $res .= $tablename . ' - ok <br />'; * } else { * $res .= 'There was a problem with ' . $tablename . '<br />'; * ++$error_count; * } * * @package WordPress * @subpackage Plugin */ /** Load WordPress Bootstrap */ require_once dirname( __DIR__ ) . '/wp-load.php'; if ( ! function_exists( 'maybe_create_table' ) ) : /** * Creates a table in the database if it doesn't already exist. * * @since 1.0.0 * * @global wpdb $wpdb WordPress database abstraction object. * * @param string $table_name Database table name. * @param string $create_ddl SQL statement to create table. * @return bool True on success or if the table already exists. False on failure. */ function maybe_create_table( $table_name, $create_ddl ) { global $wpdb; foreach ( $wpdb->get_col( 'SHOW TABLES', 0 ) as $table ) { if ( $table === $table_name ) { return true; } } // Didn't find it, so try to create it. // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- No applicable variables for this query. $wpdb->query( $create_ddl ); // We cannot directly tell whether this succeeded! foreach ( $wpdb->get_col( 'SHOW TABLES', 0 ) as $table ) { if ( $table === $table_name ) { return true; } } return false; } endif; if ( ! function_exists( 'maybe_add_column' ) ) : /** * Adds column to database table, if it doesn't already exist. * * @since 1.0.0 * * @global wpdb $wpdb WordPress database abstraction object. * * @param string $table_name Database table name. * @param string $column_name Table column name. * @param string $create_ddl SQL statement to add column. * @return bool True on success or if the column already exists. False on failure. */ function maybe_add_column( $table_name, $column_name, $create_ddl ) { global $wpdb; // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names. foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) { if ( $column === $column_name ) { return true; } } // Didn't find it, so try to create it. // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- No applicable variables for this query. $wpdb->query( $create_ddl ); // We cannot directly tell whether this succeeded! // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names. foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) { if ( $column === $column_name ) { return true; } } return false; } endif; /** * Drops column from database table, if it exists. * * @since 1.0.0 * * @global wpdb $wpdb WordPress database abstraction object. * * @param string $table_name Database table name. * @param string $column_name Table column name. * @param string $drop_ddl SQL statement to drop column. * @return bool True on success or if the column doesn't exist. False on failure. */ function maybe_drop_column( $table_name, $column_name, $drop_ddl ) { global $wpdb; // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names. foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) { if ( $column === $column_name ) { // Found it, so try to drop it. // phpcs:ignore WordPress.DB.PreparedSQL.NotPrepared -- No applicable variables for this query. $wpdb->query( $drop_ddl ); // We cannot directly tell whether this succeeded! // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names. foreach ( $wpdb->get_col( "DESC $table_name", 0 ) as $column ) { if ( $column === $column_name ) { return false; } } } } // Else didn't find it. return true; } /** * Checks that database table column matches the criteria. * * Uses the SQL DESC for retrieving the table info for the column. It will help * understand the parameters, if you do more research on what column information * is returned by the SQL statement. Pass in null to skip checking that criteria. * * Column names returned from DESC table are case sensitive and are as listed: * * - Field * - Type * - Null * - Key * - Default * - Extra * * @since 1.0.0 * * @global wpdb $wpdb WordPress database abstraction object. * * @param string $table_name Database table name. * @param string $col_name Table column name. * @param string $col_type Table column type. * @param bool $is_null Optional. Check is null. * @param mixed $key Optional. Key info. * @param mixed $default_value Optional. Default value. * @param mixed $extra Optional. Extra value. * @return bool True, if matches. False, if not matching. */ function check_column( $table_name, $col_name, $col_type, $is_null = null, $key = null, $default_value = null, $extra = null ) { global $wpdb; $diffs = 0; // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Cannot be prepared. Fetches columns for table names. $results = $wpdb->get_results( "DESC $table_name" ); foreach ( $results as $row ) { if ( $row->Field === $col_name ) { // Got our column, check the params. if ( ( null !== $col_type ) && ( $row->Type !== $col_type ) ) { ++$diffs; } if ( ( null !== $is_null ) && ( $row->Null !== $is_null ) ) { ++$diffs; } if ( ( null !== $key ) && ( $row->Key !== $key ) ) { ++$diffs; } if ( ( null !== $default_value ) && ( $row->Default !== $default_value ) ) { ++$diffs; } if ( ( null !== $extra ) && ( $row->Extra !== $extra ) ) { ++$diffs; } if ( $diffs > 0 ) { return false; } return true; } // End if found our column. } return false; }

ميديا

“ألعاب الواقع الافتراضي: رحلة إلى عوالم تفاعلية غامرة”

يونيو 12, 2025

1٬173 أقل من دقيقة

في هذا التقرير المصور، نأخذك في جولة بصرية داخل عالم ألعاب الواقع الافتراضي (VR)، حيث تندمج التكنولوجيا مع الترفيه لخلق تجارب لا مثيل لها. من خلال نظارات الواقع الافتراضي المتطورة، يمكن للاعبين التفاعل مع بيئات ثلاثية الأبعاد، مما يتيح لهم الانغماس الكامل في الألعاب. سنستعرض أبرز الألعاب المتاحة، مثل “Beat Saber” و”Half-Life: Alyx”، التي تقدم تجارب تفاعلية مبتكرة. كما نسلط الضوء على التحديات التي تواجه هذه التقنية، مثل التكلفة المرتفعة ومشاكل الراحة أثناء الاستخدام الطويل. انضم إلينا لاكتشاف كيف يُعيد الواقع الافتراضي تعريف مفهوم اللعب ويشكل مستقبل صناعة الألعاب.