Question

Alert: This function’s access is marked private. This means it is not intended for use by plugin or theme developers, only in other core functions. It is listed here for completeness.

_wp_preview_post_thumbnail_filter( null|array|string $value,  int $post_id,  string $meta_key )

Filters post thumbnail lookup to set the post thumbnail.

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description

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参数

$value

(null|array|string) (Required) The value to return - a single metadata value, or an array of values.

$post_id

(int) (Required) Post ID.

$meta_key

(string) (Required) Meta key.

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返回值

(null|array) The default return value or the post thumbnail meta array.

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源代码

File: wp-includes/revision.php

function _wp_preview_post_thumbnail_filter( $value, $post_id, $meta_key ) {
	if ( ! $post = get_post() ) {
		return $value;
	}

	if ( empty( $_REQUEST['_thumbnail_id'] ) ||
	     empty( $_REQUEST['preview_id'] ) ||
	     $post->ID != $post_id ||
	     '_thumbnail_id' != $meta_key ||
	     'revision' == $post->post_type ||
	     $post_id != $_REQUEST['preview_id']
	) {
		return $value;
	}

	$thumbnail_id = intval( $_REQUEST['_thumbnail_id'] );
	if ( $thumbnail_id <= 0 ) {
		return '';
	}

	return strval( $thumbnail_id );
}

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更新日志

Version	description
4.6.0	Introduced.

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相关函数

Uses

• wp-includes/post.php: get_post()

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User Contributed Notes