Textarea Field

Example:

<?php
   class Textarea_Fields_Widget extends WP_Widget {
      function __construct() {
          // Instantiate the parent object
          $widget_ops = array(
             'classname' => 'widget_textarea_fields_entries',
             'description' => esc_attr__('Textarea Field Widget - Created by deshisoft', 'eye-theme')
          );
          $control_ops = array(
              'width' => 275
          );
          parent::__construct( false, 'Textarea Field Widget', $widget_ops, $control_ops );
      }
      function widget( $args, $instance ) {
          extract( $args );
          // Widget output
          $title = apply_filters('widget_title', $instance['title']);
          $textarea = apply_filters('widget_textarea', $instance['textarea']);
          echo $before_widget;
             echo '<div style="border:1px solid #ddd; background:#f6f6f6;padding:15px;">';
                echo esc_attr($title);
                echo esc_attr($textarea);
             echo '</div>';
          echo $after_widget;
      }
      function update( $new_instance, $old_instance ) {
          // Save widget options
          $instance = array();
          $instance = $old_instance;
          $instance['title'] = strip_tags( $new_instance['title'] );
          $instance['textarea'] = strip_tags( $new_instance['textarea'] );
          return $instance;
      }
      function form( $instance ) {
          // Output admin widget options form
          $title = $instance['title'];
          $textarea = $instance['textarea']; ?>
          <p><label for="<?php echo $this->get_field_id('title'); ?>"><?php _e('Title:'); ?></label>
          <input class="widefat" id="<?php echo $this->get_field_id('title'); ?>" name="<?php echo      $this->get_field_name('title'); ?>" type="text" value="<?php echo $title; ?>" /></p>
          <p><label for="<?php echo $this->get_field_id('textarea'); ?>"><?php _e('Textarea:', 'ds'); ?><textarea rows="3" class="widefat" id="<?php echo $this->get_field_id('textarea'); ?>" name="<?php echo $this->get_field_name('textarea'); ?>"><?php echo $textarea; ?></textarea></label></p>
     <?php
     }
}
function textarea_field_register_widgets() {
     register_widget( 'Textarea_Fields_Widget' );
}
add_action( 'widgets_init', 'textarea_field_register_widgets' );
?>

Theme Folder -> function.php
Add this line:

require get_template_directory() . '/inc/textarea_widget.php';   // inc folder name depend on your theme.

Download Textarea Widget Field