Hi please try below code
jquery :
$('#saveMediaButton').click(function(e) {
e.preventDefault();
$.ajax({
url : my_ajax_object.ajax_url,
type : 'post',
data : {
action : 'action_upload_img',
image_attachment_id : document.getElementById("image-preview").getAttribute('src')
},
dataType : 'html',
success : function( response ) {
var jsonData = response;
console.log(response);
console.log(document.getElementById("image-preview").getAttribute('src'));
},
error : function(jqxhr, textStatus, errorThrown) {
console.log(my_ajax_object.ajax_url);
console.log(jqxhr);
console.log(textStatus);
console.log(errorThrown);
},
});
});
PHP Code :
add_action( 'wp_ajax_action_upload_img', 'action_upload_img' );
add_action( 'wp_ajax_nopriv_action_upload_img', 'action_upload_img' );
function action_upload_img(){
$response = [];
$response['data'] = $_POST;
//Your code
update_option( 'media_selector_attachment_id', $_POST["image_attachment_id"] );
wp_send_json( $response );
wp_die();
}