diff --git a/CHANGE.md b/CHANGE.md
index 66cb508..ad000b1 100755
--- a/CHANGE.md
+++ b/CHANGE.md
@@ -3,9 +3,12 @@ Change Log: `yii2-widget-select2`
 
 ## Version 2.1.9
 
-**Date:** _under development_
+**Date:** 25-Sep-2020
 
+- (enh #330): Fix select all for option values containing hyphen.
 - (enh #329): Minor fixes to select2 krajee theme.
+- (enh #328): Fix undefined options in select all.
+- (enh #325): Use `hashVarLoadPosition` to initialize Select2 hash variable.
 
 ## Version 2.1.8
 
diff --git a/src/Select2.php b/src/Select2.php
index 8dd335a..90cf487 100644
--- a/src/Select2.php
+++ b/src/Select2.php
@@ -9,6 +9,7 @@
 
 namespace kartik\select2;
 
+use Exception;
 use kartik\base\AddonTrait;
 use kartik\base\InputWidget;
 use ReflectionException;
@@ -18,8 +19,8 @@
 use yii\helpers\Inflector;
 use yii\helpers\ArrayHelper;
 use yii\helpers\Json;
+use Yii\validators\RequiredValidator;
 use yii\web\JsExpression;
-use yii\web\View;
 
 /**
  * Select2 widget is a Yii2 wrapper for the Select2 jQuery plugin. This input widget is a jQuery based replacement for
@@ -33,6 +34,7 @@
 class Select2 extends InputWidget
 {
     use AddonTrait;
+
     /**
      * Select2 large input size
      */
@@ -210,6 +212,7 @@ public function run()
      * Initializes and renders the widget
      * @throws ReflectionException
      * @throws InvalidConfigException
+     * @throws Exception
      */
     public function renderWidget()
     {
@@ -311,6 +314,7 @@ protected function renderToggleAll()
 
     /**
      * Initializes the placeholder for Select2
+     * @throws Exception
      */
     protected function initPlaceholder()
     {
@@ -338,6 +342,7 @@ protected function initPlaceholder()
      *
      * @return string
      * @throws InvalidConfigException
+     * @throws Exception
      */
     protected function embedAddon($input)
     {
@@ -432,14 +437,17 @@ public function registerAssets()
         $this->_s2OptionsVar = 's2options_' . hash('crc32', $options);
         $this->options['data-s2-options'] = $this->_s2OptionsVar;
         $view = $this->getView();
-        $view->registerJs("var {$this->_s2OptionsVar} = {$options};", View::POS_HEAD);
+        $view->registerJs("var {$this->_s2OptionsVar} = {$options};", $this->hashVarLoadPosition);
         if ($this->maintainOrder) {
             $val = Json::encode(is_array($this->value) ? $this->value : [$this->value]);
             $view->registerJs("initS2Order('{$id}',{$val});");
         }
         $this->registerPlugin($this->pluginName, "jQuery('#{$id}')", "initS2Loading('{$id}','{$this->_s2OptionsVar}')");
     }
-    
+
+    /**
+     * @return bool
+     */
     protected function isRequired()
     {
         if (!empty($this->options['required'])) {
@@ -448,9 +456,9 @@ protected function isRequired()
         if (!$this->hasModel()) {
             return false;
         }
-        $validators = $this->model->getValidators($this->attribute);
+        $validators = $this->model->getActiveValidators($this->attribute);
         foreach ($validators as $validator) {
-            if ($validator instanceof yii\validators\RequiredValidator) {
+            if ($validator instanceof RequiredValidator) {
                 return true;
             }
         }
diff --git a/src/assets/css/select2-krajee-bs4.css b/src/assets/css/select2-krajee-bs4.css
index 62088b1..23299f6 100644
--- a/src/assets/css/select2-krajee-bs4.css
+++ b/src/assets/css/select2-krajee-bs4.css
@@ -384,6 +384,7 @@
 /**
  * Bootstrap validation states
  */
+select.is-invalid + .select2-container--krajee-bs4 .select2-selection--single,
 .has-error.select2-container--krajee-bs4 .select2-dropdown,
 .has-error .select2-container--krajee-bs4 .select2-selection {
     border-color: #dc3545;
@@ -395,6 +396,7 @@
     border-color: #dc3545;
 }
 
+select.is-valid + .select2-container--krajee-bs4 .select2-selection--single,
 .has-success.select2-container--krajee-bs4 .select2-dropdown,
 .has-success .select2-container--krajee-bs4 .select2-selection {
     border-color: #28a745;
diff --git a/src/assets/js/select2-krajee.js b/src/assets/js/select2-krajee.js
index 7b53fbd..1ab2b75 100644
--- a/src/assets/js/select2-krajee.js
+++ b/src/assets/js/select2-krajee.js
@@ -38,13 +38,16 @@ var initS2ToggleAll = function () {
         }
         listenTogAll = function () {
             $tog.off('.krajees2').on('click.krajees2', function () {
-                var isSelect = $tog.hasClass('s2-togall-select'), ev = 'selectall', val;
+                var isSelect = $tog.hasClass('s2-togall-select'), ev = 'selectall', opts, val;
                 if (!isSelect) {
                     ev = 'unselectall';
                 }
                 $('#select2-' + id + '-results .select2-results__option[role="option"]').each(function () {
-                    val = $(this).attr('id').split('-').pop();
-                    $el.find('option:not([disabled])[value="' + val + '"]').prop('selected', !!isSelect);
+                    opts = $(this).attr('id').match(/^select2-[^-]*-result-.{4}-(.*)$/);
+                    if (opts.length && opts[1]) {
+                        val = opts[1];
+                        $el.find('option:not([disabled])[value="' + val + '"]').prop('selected', !!isSelect);
+                    }
                 });
                 $el.select2('close').trigger('krajeeselect2:' + ev).trigger('change');
             });
@@ -102,10 +105,13 @@ var initS2ToggleAll = function () {
         }
     };
     initS2Unselect = function () {
-        var $el = $(this), opts = $el.data('select2').options;
-        opts.set('disabled', true);
+        var $el = $(this), select2 = $el.data('select2');
+        if (!select2 || !select2.options) {
+            return;
+        }
+        select2.options.set('disabled', true);
         setTimeout(function () {
-            opts.set('disabled', false);
+            select2.options.set('disabled', false);
             $el.trigger('krajeeselect2:cleared');
         }, 1);
     };
@@ -169,7 +175,7 @@ var initS2ToggleAll = function () {
         setTimeout(function () {
             if ($el.attr('multiple') && $el.attr('dir') === 'rtl') {
                 $el.parent().find('.select2-search__field').css({width: '100%', direction: 'rtl'});
-                $el.parent().find('.select2-search--inline').css({float: 'none'});
+                $el.parent().find('.select2-search--inline').css({"float": "none"});
             }
         }, 100);
     };
diff --git a/src/assets/js/select2-krajee.min.js b/src/assets/js/select2-krajee.min.js
index e8f84c8..af32212 100644
--- a/src/assets/js/select2-krajee.min.js
+++ b/src/assets/js/select2-krajee.min.js
@@ -7,4 +7,4 @@
  * Author: Kartik Visweswaran
  * For more JQuery plugins visit http://plugins.krajee.com
  * For more Yii related demos visit http://demos.krajee.com
- */var initS2ToggleAll=function(){},initS2Order=function(){},initS2Loading=function(){},initS2Change=function(){},initS2Unselect=function(){};!function(e){"use strict";"function"==typeof define&&define.amd?define(["jquery"],e):"object"==typeof module&&module.exports?module.exports=e(require("jquery")):e(window.jQuery)}(function(e){"use strict";initS2ToggleAll=function(t){var n,s=e("#"+t),l="#s2-togall-"+t,o=e(l);s.attr("multiple")&&(n=function(){o.off(".krajees2").on("click.krajees2",function(){var n,l=o.hasClass("s2-togall-select"),i="selectall";l||(i="unselectall"),e("#select2-"+t+'-results .select2-results__option[role="option"]').each(function(){n=e(this).attr("id").split("-").pop(),s.find('option:not([disabled])[value="'+n+'"]').prop("selected",!!l)}),s.select2("close").trigger("krajeeselect2:"+i).trigger("change")})},s.on("select2:open.krajees2",function(){var i="input.krajees2 keyup.krajees2";o.parent().attr("id")!=="parent-"+l&&s.attr("multiple")&&(e("#select2-"+t+"-results").closest(".select2-dropdown").prepend(o),e("#parent-"+l).remove(),e(this).parent().find(".select2-search__field").off(i).on(i,function(){setTimeout(function(){var s="#select2-"+t+'-results .select2-results__option[role="option"]',l=s+'[aria-selected="true"]',i=e(s).length;o.removeClass("s2-togall-select s2-togall-unselect"),i>0&&e(l).length===i?o.addClass("s2-togall-unselect"):o.addClass("s2-togall-select"),n()},100)}))}).on("change.krajees2",function(){if(s.attr("multiple")){var t=0,l=s.val()?s.val().length:0;o.removeClass("s2-togall-select s2-togall-unselect"),s.find("option:enabled").each(function(){e(this).val().length&&t++}),0===t||l!==t?o.addClass("s2-togall-select"):o.addClass("s2-togall-unselect"),n()}}),n())},initS2Change=function(t){t=t||e(this);var n,s,l=e(".select2-container--open"),o=t.parents("[class*='has-']");if(o.length)for(n=o[0].className.split(/\s+/),s=0;s<n.length;s++)n[s].match("has-")&&l.removeClass("has-success has-error has-warning").addClass(n[s])},initS2Unselect=function(){var t=e(this),n=t.data("select2").options;n.set("disabled",!0),setTimeout(function(){n.set("disabled",!1),t.trigger("krajeeselect2:cleared")},1)},initS2Order=function(t,n){var s=e("#"+t);n&&n.length&&(e.each(n,function(e,t){s.find('option[value="'+t+'"]').appendTo(s)}),s.find("option:not(:selected)").appendTo(s))},initS2Loading=function(t,n){var s=window[n]||{},l=s.themeCss,o=s.sizeCss,i=s.doOrder,a=s.doReset,r=s.doToggle,c=e("#"+t),d=e(l),u=e(".kv-plugin-loading.loading-"+t),f=e(".group-"+t);c.off(".krajees2"),d.length||c.show(),f.length&&f.removeClass("kv-input-group-hide").removeClass(".group-"+t),u.length&&u.remove(),o&&c.next(l).removeClass(o).addClass(o),a&&c.closest("form").off(".krajees2").on("reset.krajees2",function(){setTimeout(function(){c.trigger("change").trigger("krajeeselect2:reset")},100)}),r&&initS2ToggleAll(t),i&&c.on("select2:select.krajees2 select2:unselect.krajees2",function(t){var n=e(t.params.data.element);n&&n.length&&(n.detach(),c.append(n).find("option:not(:selected)").appendTo(c))}),c.on("change.krajees2",function(){setTimeout(initS2Change,500)}).on("select2:unselecting.krajees2",initS2Unselect),setTimeout(function(){c.attr("multiple")&&"rtl"===c.attr("dir")&&(c.parent().find(".select2-search__field").css({width:"100%",direction:"rtl"}),c.parent().find(".select2-search--inline").css({float:"none"}))},100)}});
\ No newline at end of file
+ */var initS2ToggleAll=function(){},initS2Order=function(){},initS2Loading=function(){},initS2Change=function(){},initS2Unselect=function(){};!function(e){"use strict";"function"==typeof define&&define.amd?define(["jquery"],e):"object"==typeof module&&module.exports?module.exports=e(require("jquery")):e(window.jQuery)}(function(e){"use strict";initS2ToggleAll=function(t){var n,s=e("#"+t),l="#s2-togall-"+t,o=e(l);s.attr("multiple")&&(n=function(){o.off(".krajees2").on("click.krajees2",function(){var n,l,i=o.hasClass("s2-togall-select"),a="selectall";i||(a="unselectall"),e("#select2-"+t+'-results .select2-results__option[role="option"]').each(function(){n=e(this).attr("id").match(/^select2-[^-]*-result-.{4}-(.*)$/),n.length&&n[1]&&(l=n[1],s.find('option:not([disabled])[value="'+l+'"]').prop("selected",!!i))}),s.select2("close").trigger("krajeeselect2:"+a).trigger("change")})},s.on("select2:open.krajees2",function(){var i="input.krajees2 keyup.krajees2";o.parent().attr("id")!=="parent-"+l&&s.attr("multiple")&&(e("#select2-"+t+"-results").closest(".select2-dropdown").prepend(o),e("#parent-"+l).remove(),e(this).parent().find(".select2-search__field").off(i).on(i,function(){setTimeout(function(){var s="#select2-"+t+'-results .select2-results__option[role="option"]',l=s+'[aria-selected="true"]',i=e(s).length;o.removeClass("s2-togall-select s2-togall-unselect"),i>0&&e(l).length===i?o.addClass("s2-togall-unselect"):o.addClass("s2-togall-select"),n()},100)}))}).on("change.krajees2",function(){if(s.attr("multiple")){var t=0,l=s.val()?s.val().length:0;o.removeClass("s2-togall-select s2-togall-unselect"),s.find("option:enabled").each(function(){e(this).val().length&&t++}),0===t||l!==t?o.addClass("s2-togall-select"):o.addClass("s2-togall-unselect"),n()}}),n())},initS2Change=function(t){t=t||e(this);var n,s,l=e(".select2-container--open"),o=t.parents("[class*='has-']");if(o.length)for(n=o[0].className.split(/\s+/),s=0;s<n.length;s++)n[s].match("has-")&&l.removeClass("has-success has-error has-warning").addClass(n[s])},initS2Unselect=function(){var t=e(this),n=t.data("select2");n&&n.options&&(n.options.set("disabled",!0),setTimeout(function(){n.options.set("disabled",!1),t.trigger("krajeeselect2:cleared")},1))},initS2Order=function(t,n){var s=e("#"+t);n&&n.length&&(e.each(n,function(e,t){s.find('option[value="'+t+'"]').appendTo(s)}),s.find("option:not(:selected)").appendTo(s))},initS2Loading=function(t,n){var s=window[n]||{},l=s.themeCss,o=s.sizeCss,i=s.doOrder,a=s.doReset,r=s.doToggle,c=e("#"+t),u=e(l),d=e(".kv-plugin-loading.loading-"+t),g=e(".group-"+t);c.off(".krajees2"),u.length||c.show(),g.length&&g.removeClass("kv-input-group-hide").removeClass(".group-"+t),d.length&&d.remove(),o&&c.next(l).removeClass(o).addClass(o),a&&c.closest("form").off(".krajees2").on("reset.krajees2",function(){setTimeout(function(){c.trigger("change").trigger("krajeeselect2:reset")},100)}),r&&initS2ToggleAll(t),i&&c.on("select2:select.krajees2 select2:unselect.krajees2",function(t){var n=e(t.params.data.element);n&&n.length&&(n.detach(),c.append(n).find("option:not(:selected)").appendTo(c))}),c.on("change.krajees2",function(){setTimeout(initS2Change,500)}).on("select2:unselecting.krajees2",initS2Unselect),setTimeout(function(){c.attr("multiple")&&"rtl"===c.attr("dir")&&(c.parent().find(".select2-search__field").css({width:"100%",direction:"rtl"}),c.parent().find(".select2-search--inline").css({"float":"none"}))},100)}});
\ No newline at end of file