wp_check_filetype_and_ext()

尝试确定文件的实际文件类型。

原型

wp_check_filetype_and_ext( string $file, string $filename, array $mimes = null )

描述

如果不能，则使用文件扩展名来确定类型。

参数

$file (string) (Required) 文件的完整路径。

$filename (string) (Required) 文件名（由于$ file位于tmp目录中，可能与$ file不同）。

$mimes (array) (Optional)  Key是文件扩展名，其值为mime类型。

返回值

(array)  扩展名，MIME和更正的文件名的值，如果原始$ filename有效，则为false。

源文件

路径：wp-includes/functions.php

<?php
...
function wp_check_filetype_and_ext( $file, $filename, $mimes = null ) {
	$proper_filename = false;
	// Do basic extension validation and MIME mapping
	$wp_filetype = wp_check_filetype( $filename, $mimes );
	$ext = $wp_filetype['ext'];
	$type = $wp_filetype['type'];
	// We can't do any further validation without a file to work with
	if ( ! file_exists( $file ) ) {
		return compact( 'ext', 'type', 'proper_filename' );
	}
	$real_mime = false;
	// Validate image types.
	if ( $type && 0 === strpos( $type, 'image/' ) ) {
		// Attempt to figure out what type of image it actually is
		$real_mime = wp_get_image_mime( $file );
		if ( $real_mime && $real_mime != $type ) {
			/**
			 * Filters the list mapping image mime types to their respective extensions.
			 *
			 * @since 3.0.0
			 *
			 * @param  array $mime_to_ext Array of image mime types and their matching extensions.
			 */
			$mime_to_ext = apply_filters( 'getimagesize_mimes_to_exts', array(
				'image/jpeg' => 'jpg',
				'image/png'  => 'png',
				'image/gif'  => 'gif',
				'image/bmp'  => 'bmp',
				'image/tiff' => 'tif',
			) );
			// Replace whatever is after the last period in the filename with the correct extension
			if ( ! empty( $mime_to_ext[ $real_mime ] ) ) {
				$filename_parts = explode( '.', $filename );
				array_pop( $filename_parts );
				$filename_parts[] = $mime_to_ext[ $real_mime ];
				$new_filename = implode( '.', $filename_parts );
				if ( $new_filename != $filename ) {
					$proper_filename = $new_filename; // Mark that it changed
				}
				// Redefine the extension / MIME
				$wp_filetype = wp_check_filetype( $new_filename, $mimes );
				$ext = $wp_filetype['ext'];
				$type = $wp_filetype['type'];
			} else {
				// Reset $real_mime and try validating again.
				$real_mime = false;
			}
		}
	}
	// Validate files that didn't get validated during previous checks.
	if ( $type && ! $real_mime && extension_loaded( 'fileinfo' ) ) {
		$finfo = finfo_open( FILEINFO_MIME_TYPE );
		$real_mime = finfo_file( $finfo, $file );
		finfo_close( $finfo );
		/*
		 * If $real_mime doesn't match what we're expecting, we need to do some extra
		 * vetting of application mime types to make sure this type of file is allowed.
		 * Other mime types are assumed to be safe, but should be considered unverified.
		 */
		if ( $real_mime && ( $real_mime !== $type ) && ( 0 === strpos( $real_mime, 'application' ) ) ) {
			$allowed = get_allowed_mime_types();
			if ( ! in_array( $real_mime, $allowed ) ) {
				$type = $ext = false;
			}
		}
	}
	/**
	 * Filters the "real" file type of the given file.
	 *
	 * @since 3.0.0
	 *
	 * @param array  $wp_check_filetype_and_ext File data array containing 'ext', 'type', and
	 *                                          'proper_filename' keys.
	 * @param string $file                      Full path to the file.
	 * @param string $filename                  The name of the file (may differ from $file due to
	 *                                          $file being in a tmp directory).
	 * @param array  $mimes                     Key is the file extension with value as the mime type.
	 */
	return apply_filters( 'wp_check_filetype_and_ext', compact( 'ext', 'type', 'proper_filename' ), $file, $filename, $mimes );
}
...
?>

其他

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