Wordpress Custom Widget Select Options Not Saving - wordpress

Question

I'm very new to coding Wordpress plugins/widgets (this is my first time!). I've built a very basic Wordpress plugin which consists of 2 text inputs and a select field. The text inputs work fine however the select box doesn't appear to be saving when I hit the "Save" button.
Here is my plugin code:
<?php
/* Plugin Name: Sidebar Box
Plugin URI: http://www.website.com
Description: Displays contact box in sidebar
Version: 1.0
Author: JM
Author URI: N/A
*/
// use widgets_init action hook to execute custom function
add_action( 'widgets_init', 'jm_box_widget' );
//register our widget
function jm_box_widget() {
register_widget( 'jm_box_widget_my_info' );
}
//boj_widget_my_info class
class jm_box_widget_my_info extends WP_Widget {
//process the new widget
function jm_box_widget_my_info() {
$widget_ops = array(
'classname' => 'jm_box_widget_class',
'description' => 'Sidebar Box Widget.'
);
$this->WP_Widget( 'jm_box_widget_my_info', 'Box Widget', $widget_ops );
}
//build the widget settings form
function form($instance) {
$defaults = array( 'title' => 'Box Page Widget', 'description' => '', 'boxtype' => '' );
$instance = wp_parse_args( (array) $instance, $defaults );
$title = $instance['title'];
$description = $instance['description'];
$boxtype = $instance['boxtype'];
?>
<p>Title: <input class="widefat" name="<?php echo $this->get_field_name( 'title' ); ?>" type="text" value="<?php echo esc_attr( $title ); ?>" /></p>
<p>Description: <textarea class="widefat" name="<?php echo $this->get_field_name( 'description' ); ?>" / ><?php echo esc_attr( $description ); ?></textarea></p>
<p>Sex:
<select id="<?php echo $this->get_field_id( 'boxtype' ); ?>" name="<?php echo $this->get_field_name( 'boxtype' ); ?>" class="widefat" style="width:100%;">
<option <?php if ( 'box1' == $instance['format'] ) echo 'selected="selected"'; ?> value="box1">box1</option>
<option <?php if ( 'box2' == $instance['format'] ) echo 'selected="selected"'; ?> value="box2">box2</option>
</select>
</p>
<?php
}
//save the widget settings
function update($new_instance, $old_instance) {
$instance = $old_instance;
$instance['title'] = strip_tags( $new_instance['title'] );
$instance['description'] = strip_tags( $new_instance['description'] );
$instance['boxtype'] = ( $new_instance['boxtype'] );
return $instance;
}
//display the widget
function widget($args, $instance) {
extract($args);
echo $before_widget;
$title = apply_filters( 'widget_title', $instance['title'] );
$description = empty( $instance['description'] ) ? ' ' : $instance['description'];
$boxtype = empty( $instance['boxtype'] ) ? ' ' : $instance['boxtype'];
echo '<div class="sidebar-box" id="' . $boxtype . '" onmouseover="this.style.cursor=\'pointer\'" onmouseup="window.location=\'' . $boxtype . '\'">
<h3>' . $title . '</h3>
<p>' . $description . '</p>
</div>';
echo $after_widget;
}
}
?>
I can't for the life of me workout why it's not saving.
Any help would be greatly appreciated.
Thanks,
James

Answer 1

Somewhere along the line you must have changed $instance['format'] to $instance['boxtype'] but not in the form. The options need changing.
<option <?php if ('box1' == $boxtype )