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function is not described

get_image_tag() WP 2.5.0

Gets an img tag for an image attachment, scaling it down if requested.

The 'get_image_tag_class' filter allows for changing the class name for the image without having to use regular expressions on the HTML content. The parameters are: what WordPress will use for the class, the Attachment ID, image align value, and the size the image should be.

The second filter, 'get_image_tag', has the HTML content, which can then be further manipulated by a plugin to change all attribute values and even HTML content.

Hooks in function
Return

String. HTML IMG element for given image attachment

Usage

get_image_tag( $id, $alt, $title, $align, $size );
$id(int) (required)
Attachment ID.
$alt(string) (required)
Image Description for the alt attribute.
$title(string) (required)
Image Description for the title attribute.
$align(string) (required)
Part of the class name for aligning the image.
$size(string/array)
Registered image size to retrieve a tag for. Accepts any valid image size, or an array of width and height values in pixels (in that order).
Default: 'medium'

Code of get image tag: wp-includes/media.php VER 5.1.1

<?php
function get_image_tag( $id, $alt, $title, $align, $size = 'medium' ) {

	list( $img_src, $width, $height ) = image_downsize( $id, $size );
	$hwstring                         = image_hwstring( $width, $height );

	$title = $title ? 'title="' . esc_attr( $title ) . '" ' : '';

	$class = 'align' . esc_attr( $align ) . ' size-' . esc_attr( $size ) . ' wp-image-' . $id;

	/**
	 * Filters the value of the attachment's image tag class attribute.
	 *
	 * @since 2.6.0
	 *
	 * @param string       $class CSS class name or space-separated list of classes.
	 * @param int          $id    Attachment ID.
	 * @param string       $align Part of the class name for aligning the image.
	 * @param string|array $size  Size of image. Image size or array of width and height values (in that order).
	 *                            Default 'medium'.
	 */
	$class = apply_filters( 'get_image_tag_class', $class, $id, $align, $size );

	$html = '<img src="' . esc_attr( $img_src ) . '" alt="' . esc_attr( $alt ) . '" ' . $title . $hwstring . 'class="' . $class . '" />';

	/**
	 * Filters the HTML content for the image tag.
	 *
	 * @since 2.6.0
	 *
	 * @param string       $html  HTML content for the image.
	 * @param int          $id    Attachment ID.
	 * @param string       $alt   Alternate text.
	 * @param string       $title Attachment title.
	 * @param string       $align Part of the class name for aligning the image.
	 * @param string|array $size  Size of image. Image size or array of width and height values (in that order).
	 *                            Default 'medium'.
	 */
	return apply_filters( 'get_image_tag', $html, $id, $alt, $title, $align, $size );
}