块编辑器中的所有当前数据都存储在数据存储中。如果单击“保存”按钮，该数据将通过REST API发送到数据库。您可以从存储中选择数据并订阅更改。

// Create a higher-order component that updates automatically when featured image changes.
const applyWithSelect = withSelect( ( select ) => {
    const { getMedia } = select( \'core\' );
    const { getEditedPostAttribute } = select( \'core/editor\' );
    const featuredImageId = getEditedPostAttribute( \'featured_media\' );

    return {
        media: featuredImageId ? getMedia( featuredImageId ) : null,
        featuredImageId,
    };
} );

export default compose( [
    applyWithSelect,
] )( MyCustomBlockEdit );

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