Create dropdown HTML content of users.

The content can either be displayed, which it is by default or retrieved by setting the ‘echo’ argument. The ‘include’ and ‘exclude’ arguments do not need to be used; all users will be displayed in that case. Only one can be used, either ‘include’ or ‘exclude’, but not both.

The available arguments are as follows:

Signature

wp_dropdown_users( $args = '' )
args
 (array|string) Optional. Array or string of arguments to generate a drop-down of users.
Default: ''

Return

(string|null) Null on display. String of HTML content on retrieve.

Source

function wp_dropdown_users( $args = '' ) {
	$defaults = array(
		'show_option_all' => '', 'show_option_none' => '', 'hide_if_only_one_author' => '',
		'orderby' => 'display_name', 'order' => 'ASC',
		'include' => '', 'exclude' => '', 'multi' => 0,
		'show' => 'display_name', 'echo' => 1,
		'selected' => 0, 'name' => 'user', 'class' => '', 'id' => '',
		'blog_id' => $GLOBALS['blog_id'], 'who' => '', 'include_selected' => false,
		'option_none_value' => -1
	);

	$defaults['selected'] = is_author() ? get_query_var( 'author' ) : 0;

	$r = wp_parse_args( $args, $defaults );
	$show = $r['show'];
	$show_option_all = $r['show_option_all'];
	$show_option_none = $r['show_option_none'];
	$option_none_value = $r['option_none_value'];

	$query_args = wp_array_slice_assoc( $r, array( 'blog_id', 'include', 'exclude', 'orderby', 'order', 'who' ) );
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