image_get_intermediate_size()

检索图像的中间大小（已调整大小）路径，宽度和高度。

原型

image_get_intermediate_size( int $post_id, array|string $size = 'thumbnail' )

描述

$ size参数可以是分别具有宽度和高度的数组。如果大小与’sizes’元数据数组的宽度和高度匹配，那么将使用它。如果没有直接匹配，则将使用大于指定大小的最近图像大小。如果找不到任何内容，则该函数将中断并返回false。

参数

$post_id (int) (Required) 附件ID。

$size (array|string) (Optional)  图片尺寸。接受任何有效的图像大小，或以像素为单位的宽度和高度值数组（按此顺序）。

返回值

(false|array)  $ data {成功时文件相对路径，宽度和高度的数组。如果已将注册大小传递给$ size参数，则还包括绝对路径和URL。失败时是假的。 @type string $ file图像相对于上传目录的路径@type int $ width图像的宽度@type int $ height图像的高度@type string $ path图像的绝对文件系统路径。 @type string $ url图片的URL。 }

源文件

路径：wp-includes/media.php

<?php
...
function image_get_intermediate_size( $post_id, $size = 'thumbnail' ) {
	if ( ! $size || ! is_array( $imagedata = wp_get_attachment_metadata( $post_id ) ) || empty( $imagedata['sizes'] )  ) {
		return false;
	}
	$data = array();
	// Find the best match when '$size' is an array.
	if ( is_array( $size ) ) {
		$candidates = array();
		if ( ! isset( $imagedata['file'] ) && isset( $imagedata['sizes']['full'] ) ) {
			$imagedata['height'] = $imagedata['sizes']['full']['height'];
			$imagedata['width']  = $imagedata['sizes']['full']['width'];
		}
		foreach ( $imagedata['sizes'] as $_size => $data ) {
			// If there's an exact match to an existing image size, short circuit.
			if ( $data['width'] == $size[0] && $data['height'] == $size[1] ) {
				$candidates[ $data['width'] * $data['height'] ] = $data;
				break;
			}
			// If it's not an exact match, consider larger sizes with the same aspect ratio.
			if ( $data['width'] >= $size[0] && $data['height'] >= $size[1] ) {
				// If '0' is passed to either size, we test ratios against the original file.
				if ( 0 === $size[0] || 0 === $size[1] ) {
					$same_ratio = wp_image_matches_ratio( $data['width'], $data['height'], $imagedata['width'], $imagedata['height'] );
				} else {
					$same_ratio = wp_image_matches_ratio( $data['width'], $data['height'], $size[0], $size[1] );
				}
				if ( $same_ratio ) {
					$candidates[ $data['width'] * $data['height'] ] = $data;
				}
			}
		}
		if ( ! empty( $candidates ) ) {
			// Sort the array by size if we have more than one candidate.
			if ( 1 < count( $candidates ) ) {
				ksort( $candidates );
			}
			$data = array_shift( $candidates );
		/*
		 * When the size requested is smaller than the thumbnail dimensions, we
		 * fall back to the thumbnail size to maintain backwards compatibility with
		 * pre 4.6 versions of WordPress.
		 */
		} elseif ( ! empty( $imagedata['sizes']['thumbnail'] ) && $imagedata['sizes']['thumbnail']['width'] >= $size[0] && $imagedata['sizes']['thumbnail']['width'] >= $size[1] ) {
			$data = $imagedata['sizes']['thumbnail'];
		} else {
			return false;
		}
		// Constrain the width and height attributes to the requested values.
		list( $data['width'], $data['height'] ) = image_constrain_size_for_editor( $data['width'], $data['height'], $size );
	} elseif ( ! empty( $imagedata['sizes'][ $size ] ) ) {
		$data = $imagedata['sizes'][ $size ];
	}
	// If we still don't have a match at this point, return false.
	if ( empty( $data ) ) {
		return false;
	}
	// include the full filesystem path of the intermediate file
	if ( empty( $data['path'] ) && ! empty( $data['file'] ) && ! empty( $imagedata['file'] ) ) {
		$file_url = wp_get_attachment_url($post_id);
		$data['path'] = path_join( dirname($imagedata['file']), $data['file'] );
		$data['url'] = path_join( dirname($file_url), $data['file'] );
	}
	/**
	 * Filters the output of image_get_intermediate_size()
	 *
	 * @since 4.4.0
	 *
	 * @see image_get_intermediate_size()
	 *
	 * @param array        $data    Array of file relative path, width, and height on success. May also include
	 *                              file absolute path and URL.
	 * @param int          $post_id The post_id of the image attachment
	 * @param string|array $size    Registered image size or flat array of initially-requested height and width
	 *                              dimensions (in that order).
	 */
	return apply_filters( 'image_get_intermediate_size', $data, $post_id, $size );
}
...
?>

其他

英文文档：https://developer.wordpress.org/reference/functions/image_get_intermediate_size/