Question

WP_Roles

Core class used to implement a user roles API.

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description

The role option is simple, the structure is organized by role name that store the name in value of the ‘name’ key. The capabilities are stored as an array in the value of the ‘capability’ key.

array (
    'rolename' => array (
        'name' => 'rolename',
        'capabilities' => array()
    )
)

---

源代码

File: wp-includes/class-wp-roles.php

class WP_Roles {
	/**
	 * List of roles and capabilities.
	 *
	 * @since 2.0.0
	 * @access public
	 * @var array
	 */
	public $roles;

	/**
	 * List of the role objects.
	 *
	 * @since 2.0.0
	 * @access public
	 * @var array
	 */
	public $role_objects = array();

	/**
	 * List of role names.
	 *
	 * @since 2.0.0
	 * @access public
	 * @var array
	 */
	public $role_names = array();

	/**
	 * Option name for storing role list.
	 *
	 * @since 2.0.0
	 * @access public
	 * @var string
	 */
	public $role_key;

	/**
	 * Whether to use the database for retrieval and storage.
	 *
	 * @since 2.1.0
	 * @access public
	 * @var bool
	 */
	public $use_db = true;

	/**
	 * Constructor
	 *
	 * @since 2.0.0
	 */
	public function __construct() {
		$this->_init();
	}

	/**
	 * Make private/protected methods readable for backward compatibility.
	 *
	 * @since 4.0.0
	 * @access public
	 *
	 * @param callable $name      Method to call.
	 * @param array    $arguments Arguments to pass when calling.
	 * @return mixed|false Return value of the callback, false otherwise.
	 */
	public function __call( $name, $arguments ) {
		if ( '_init' === $name ) {
			return call_user_func_array( array( $this, $name ), $arguments );
		}
		return false;
	}

	/**
	 * Set up the object properties.
	 *
	 * The role key is set to the current prefix for the $wpdb object with
	 * 'user_roles' appended. If the $wp_user_roles global is set, then it will
	 * be used and the role option will not be updated or used.
	 *
	 * @since 2.1.0
	 * @access protected
	 *
	 * @global array $wp_user_roles Used to set the 'roles' property value.
	 */
	protected function _init() {
		global $wp_user_roles, $wpdb;

		$this->role_key = $wpdb->get_blog_prefix() . 'user_roles';
		if ( ! empty( $wp_user_roles ) ) {
			$this->roles = $wp_user_roles;
			$this->use_db = false;
		} else {
			$this->roles = get_option( $this->role_key );
		}

		if ( empty( $this->roles ) )
			return;

		$this->role_objects = array();
		$this->role_names =  array();
		foreach ( array_keys( $this->roles ) as $role ) {
			$this->role_objects[$role] = new WP_Role( $role, $this->roles[$role]['capabilities'] );
			$this->role_names[$role] = $this->roles[$role]['name'];
		}

		/**
		 * After the roles have been initialized, allow plugins to add their own roles.
		 *
		 * @since 4.7.0
		 *
		 * @param WP_Roles $this A reference to the WP_Roles object.
		 */
		do_action( 'wp_roles_init', $this );
	}

	/**
	 * Reinitialize the object
	 *
	 * Recreates the role objects. This is typically called only by switch_to_blog()
	 * after switching wpdb to a new site ID.
	 *
	 * @since 3.5.0
	 * @deprecated 4.7.0 Use new WP_Roles()
	 * @access public
	 */
	public function reinit() {
		_deprecated_function( __METHOD__, '4.7.0', 'new WP_Roles()' );
		$this->_init();
	}

	/**
	 * Add role name with capabilities to list.
	 *
	 * Updates the list of roles, if the role doesn't already exist.
	 *
	 * The capabilities are defined in the following format `array( 'read' => true );`
	 * To explicitly deny a role a capability you set the value for that capability to false.
	 *
	 * @since 2.0.0
	 * @access public
	 *
	 * @param string $role Role name.
	 * @param string $display_name Role display name.
	 * @param array $capabilities List of role capabilities in the above format.
	 * @return WP_Role|void WP_Role object, if role is added.
	 */
	public function add_role( $role, $display_name, $capabilities = array() ) {
		if ( empty( $role ) || isset( $this->roles[ $role ] ) ) {
			return;
		}

		$this->roles[$role] = array(
			'name' => $display_name,
			'capabilities' => $capabilities
			);
		if ( $this->use_db )
			update_option( $this->role_key, $this->roles );
		$this->role_objects[$role] = new WP_Role( $role, $capabilities );
		$this->role_names[$role] = $display_name;
		return $this->role_objects[$role];
	}

	/**
	 * Remove role by name.
	 *
	 * @since 2.0.0
	 * @access public
	 *
	 * @param string $role Role name.
	 */
	public function remove_role( $role ) {
		if ( ! isset( $this->role_objects[$role] ) )
			return;

		unset( $this->role_objects[$role] );
		unset( $this->role_names[$role] );
		unset( $this->roles[$role] );

		if ( $this->use_db )
			update_option( $this->role_key, $this->roles );

		if ( get_option( 'default_role' ) == $role )
			update_option( 'default_role', 'subscriber' );
	}

	/**
	 * Add capability to role.
	 *
	 * @since 2.0.0
	 * @access public
	 *
	 * @param string $role Role name.
	 * @param string $cap Capability name.
	 * @param bool $grant Optional, default is true. Whether role is capable of performing capability.
	 */
	public function add_cap( $role, $cap, $grant = true ) {
		if ( ! isset( $this->roles[$role] ) )
			return;

		$this->roles[$role]['capabilities'][$cap] = $grant;
		if ( $this->use_db )
			update_option( $this->role_key, $this->roles );
	}

	/**
	 * Remove capability from role.
	 *
	 * @since 2.0.0
	 * @access public
	 *
	 * @param string $role Role name.
	 * @param string $cap Capability name.
	 */
	public function remove_cap( $role, $cap ) {
		if ( ! isset( $this->roles[$role] ) )
			return;

		unset( $this->roles[$role]['capabilities'][$cap] );
		if ( $this->use_db )
			update_option( $this->role_key, $this->roles );
	}

	/**
	 * Retrieve role object by name.
	 *
	 * @since 2.0.0
	 * @access public
	 *
	 * @param string $role Role name.
	 * @return WP_Role|null WP_Role object if found, null if the role does not exist.
	 */
	public function get_role( $role ) {
		if ( isset( $this->role_objects[$role] ) )
			return $this->role_objects[$role];
		else
			return null;
	}

	/**
	 * Retrieve list of role names.
	 *
	 * @since 2.0.0
	 * @access public
	 *
	 * @return array List of role names.
	 */
	public function get_names() {
		return $this->role_names;
	}

	/**
	 * Whether role name is currently in the list of available roles.
	 *
	 * @since 2.0.0
	 * @access public
	 *
	 * @param string $role Role name to look up.
	 * @return bool
	 */
	public function is_role( $role ) {
		return isset( $this->role_names[$role] );
	}
}

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更新日志

Version	description
2.0.0	Introduced.

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Methods

• __call Make private/protected methods readable for backward compatibility.
• __construct Constructor
• _init Set up the object properties.
• add_cap Add capability to role.
• add_role Add role name with capabilities to list.
• get_names Retrieve list of role names.
• get_role Retrieve role object by name.
• is_role Whether role name is currently in the list of available roles.
• reinit Reinitialize the object deprecated
• remove_cap Remove capability from role.
• remove_role Remove role by name.

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User Contributed Notes