类文档

WP_Customize_Custom_CSS_Setting

💡 云策文档标注

概述

WP_Customize_Custom_CSS_Setting 是 WordPress 自定义器中用于处理自定义 CSS 设置的类,继承自 WP_Customize_Setting。它管理 CSS 值的预览、验证、存储和获取,支持通过 custom_css 自定义文章类型存储样式表相关的 CSS。

关键要点

  • 类继承自 WP_Customize_Setting,类型为 'custom_css',传输方式为 'postMessage',所需权限为 'edit_css'。
  • 构造函数验证设置 ID 格式为 `custom_css[$stylesheet]`,并设置 stylesheet 属性。
  • 提供预览功能,通过 filter_previewed_wp_get_custom_css 方法过滤 wp_get_custom_css 以应用自定义值。
  • value 方法获取设置值,优先返回预览值,否则从 custom_css 文章类型中获取。
  • validate 方法验证 CSS 值,检查非法标记,如不平衡的括号和注释,但自 4.9.0 起平衡字符检查已移至客户端。
  • update 方法将 CSS 值存储到 custom_css 自定义文章类型中,并缓存文章 ID 到主题修改中以提高性能。

代码示例

final class WP_Customize_Custom_CSS_Setting extends WP_Customize_Setting {
    public $type = 'custom_css';
    public $transport = 'postMessage';
    public $capability = 'edit_css';
    public $stylesheet = '';

    public function __construct( $manager, $id, $args = array() ) {
        parent::__construct( $manager, $id, $args );
        if ( 'custom_css' !== $this->id_data['base'] ) {
            throw new Exception( 'Expected custom_css id_base.' );
        }
        if ( 1 !== count( $this->id_data['keys'] ) || empty( $this->id_data['keys'][0] ) ) {
            throw new Exception( 'Expected single stylesheet key.' );
        }
        $this->stylesheet = $this->id_data['keys'][0];
    }

    public function preview() {
        if ( $this->is_previewed ) {
            return false;
        }
        $this->is_previewed = true;
        add_filter( 'wp_get_custom_css', array( $this, 'filter_previewed_wp_get_custom_css' ), 9, 2 );
        return true;
    }

    public function filter_previewed_wp_get_custom_css( $css, $stylesheet ) {
        if ( $stylesheet === $this->stylesheet ) {
            $customized_value = $this->post_value( null );
            if ( ! is_null( $customized_value ) ) {
                $css = $customized_value;
            }
        }
        return $css;
    }

    public function value() {
        if ( $this->is_previewed ) {
            $post_value = $this->post_value( null );
            if ( null !== $post_value ) {
                return $post_value;
            }
        }
        $id_base = $this->id_data['base'];
        $value   = '';
        $post    = wp_get_custom_css_post( $this->stylesheet );
        if ( $post ) {
            $value = $post->post_content;
        }
        if ( empty( $value ) ) {
            $value = $this->default;
        }
        $value = apply_filters( "customize_value_{$id_base}", $value, $this );
        return $value;
    }

    public function validate( $value ) {
        $css = $value;
        $validity = new WP_Error();
        if ( preg_match( '#</?w+#', $css ) ) {
            $validity->add( 'illegal_markup', __( 'Markup is not allowed in CSS.' ) );
        }
        if ( ! $validity->has_errors() ) {
            $validity = parent::validate( $css );
        }
        return $validity;
    }

    public function update( $value ) {
        $css = $value;
        if ( empty( $css ) ) {
            $css = '';
        }
        $r = wp_update_custom_css_post(
            $css,
            array(
                'stylesheet' => $this->stylesheet,
            )
        );
        if ( is_wp_error( $r ) ) {
            return false;
        }
        $post_id = $r->ID;
        if ( $this->manager->get_stylesheet() === $this->stylesheet ) {
            set_theme_mod( 'custom_css_post_id', $post_id );
        }
        return $post_id;
    }
}

注意事项

  • 自 4.9.0 版本起,CSS 平衡字符(如括号)的验证已移至客户端代码编辑器中的 linting 工具,服务器端仅检查非法标记。
  • 设置 ID 必须符合 `custom_css[$stylesheet]` 格式,否则构造函数会抛出异常。
  • 预览功能通过添加 wp_get_custom_css 过滤器实现,确保自定义值在预览时正确应用。
  • update 方法使用 wp_update_custom_css_post 函数存储 CSS,并缓存文章 ID 到主题修改中,以提高后续查询性能。

📄 原文内容

Custom Setting to handle WP Custom CSS.

Description

See also

Methods

Name Description
WP_Customize_Custom_CSS_Setting::__construct WP_Customize_Custom_CSS_Setting constructor.
WP_Customize_Custom_CSS_Setting::filter_previewed_wp_get_custom_css Filters `wp_get_custom_css` for applying the customized value.
WP_Customize_Custom_CSS_Setting::preview Add filter to preview post value.
WP_Customize_Custom_CSS_Setting::update Store the CSS setting value in the custom_css custom post type for the stylesheet.
WP_Customize_Custom_CSS_Setting::validate Validate a received value for being valid CSS.
WP_Customize_Custom_CSS_Setting::value Fetch the value of the setting. Will return the previewed value when `preview()` is called.

Source

final class WP_Customize_Custom_CSS_Setting extends WP_Customize_Setting {

	/**
	 * The setting type.
	 *
	 * @since 4.7.0
	 * @var string
	 */
	public $type = 'custom_css';

	/**
	 * Setting Transport
	 *
	 * @since 4.7.0
	 * @var string
	 */
	public $transport = 'postMessage';

	/**
	 * Capability required to edit this setting.
	 *
	 * @since 4.7.0
	 * @var string
	 */
	public $capability = 'edit_css';

	/**
	 * Stylesheet
	 *
	 * @since 4.7.0
	 * @var string
	 */
	public $stylesheet = '';

	/**
	 * WP_Customize_Custom_CSS_Setting constructor.
	 *
	 * @since 4.7.0
	 *
	 * @throws Exception If the setting ID does not match the pattern `custom_css[$stylesheet]`.
	 *
	 * @param WP_Customize_Manager $manager Customizer bootstrap instance.
	 * @param string               $id      A specific ID of the setting.
	 *                                      Can be a theme mod or option name.
	 * @param array                $args    Setting arguments.
	 */
	public function __construct( $manager, $id, $args = array() ) {
		parent::__construct( $manager, $id, $args );
		if ( 'custom_css' !== $this->id_data['base'] ) {
			throw new Exception( 'Expected custom_css id_base.' );
		}
		if ( 1 !== count( $this->id_data['keys'] ) || empty( $this->id_data['keys'][0] ) ) {
			throw new Exception( 'Expected single stylesheet key.' );
		}
		$this->stylesheet = $this->id_data['keys'][0];
	}

	/**
	 * Add filter to preview post value.
	 *
	 * @since 4.7.9
	 *
	 * @return bool False when preview short-circuits due no change needing to be previewed.
	 */
	public function preview() {
		if ( $this->is_previewed ) {
			return false;
		}
		$this->is_previewed = true;
		add_filter( 'wp_get_custom_css', array( $this, 'filter_previewed_wp_get_custom_css' ), 9, 2 );
		return true;
	}

	/**
	 * Filters `wp_get_custom_css` for applying the customized value.
	 *
	 * This is used in the preview when `wp_get_custom_css()` is called for rendering the styles.
	 *
	 * @since 4.7.0
	 *
	 * @see wp_get_custom_css()
	 *
	 * @param string $css        Original CSS.
	 * @param string $stylesheet Current stylesheet.
	 * @return string CSS.
	 */
	public function filter_previewed_wp_get_custom_css( $css, $stylesheet ) {
		if ( $stylesheet === $this->stylesheet ) {
			$customized_value = $this->post_value( null );
			if ( ! is_null( $customized_value ) ) {
				$css = $customized_value;
			}
		}
		return $css;
	}

	/**
	 * Fetch the value of the setting. Will return the previewed value when `preview()` is called.
	 *
	 * @since 4.7.0
	 *
	 * @see WP_Customize_Setting::value()
	 *
	 * @return string
	 */
	public function value() {
		if ( $this->is_previewed ) {
			$post_value = $this->post_value( null );
			if ( null !== $post_value ) {
				return $post_value;
			}
		}
		$id_base = $this->id_data['base'];
		$value   = '';
		$post    = wp_get_custom_css_post( $this->stylesheet );
		if ( $post ) {
			$value = $post->post_content;
		}
		if ( empty( $value ) ) {
			$value = $this->default;
		}

		/** This filter is documented in wp-includes/class-wp-customize-setting.php */
		$value = apply_filters( "customize_value_{$id_base}", $value, $this );

		return $value;
	}

	/**
	 * Validate a received value for being valid CSS.
	 *
	 * Checks for imbalanced braces, brackets, and comments.
	 * Notifications are rendered when the customizer state is saved.
	 *
	 * @since 4.7.0
	 * @since 4.9.0 Checking for balanced characters has been moved client-side via linting in code editor.
	 * @since 5.9.0 Renamed `$css` to `$value` for PHP 8 named parameter support.
	 *
	 * @param string $value CSS to validate.
	 * @return true|WP_Error True if the input was validated, otherwise WP_Error.
	 */
	public function validate( $value ) {
		// Restores the more descriptive, specific name for use within this method.
		$css = $value;

		$validity = new WP_Error();

		if ( preg_match( '#<!--?w+#', $css ) ) {
			$validity--->add( 'illegal_markup', __( 'Markup is not allowed in CSS.' ) );
		}

		if ( ! $validity->has_errors() ) {
			$validity = parent::validate( $css );
		}
		return $validity;
	}

	/**
	 * Store the CSS setting value in the custom_css custom post type for the stylesheet.
	 *
	 * @since 4.7.0
	 * @since 5.9.0 Renamed `$css` to `$value` for PHP 8 named parameter support.
	 *
	 * @param string $value CSS to update.
	 * @return int|false The post ID or false if the value could not be saved.
	 */
	public function update( $value ) {
		// Restores the more descriptive, specific name for use within this method.
		$css = $value;

		if ( empty( $css ) ) {
			$css = '';
		}

		$r = wp_update_custom_css_post(
			$css,
			array(
				'stylesheet' => $this->stylesheet,
			)
		);

		if ( is_wp_error( $r ) ) {
			return false;
		}

		$post_id = $r->ID;

		// Cache post ID in theme mod for performance to avoid additional DB query.
		if ( $this->manager->get_stylesheet() === $this->stylesheet ) {
			set_theme_mod( 'custom_css_post_id', $post_id );
		}

		return $post_id;
	}
}

Changelog

Version Description
4.7.0 Introduced.