Fixes #1610: `Html::activeCheckboxList()` and `Html::activeRadioList()` will submit an empty string if no checkbox/radio is selected

framework/CHANGELOG.md

@@ -32,7 +32,8 @@ Yii Framework 2 Change Log
 - Enh: Added `favicon.ico` and `robots.txt` to defauly application templates (samdark)
 - Enh: Added `Widget::autoIdPrefix` to support prefixing automatically generated widget IDs (qiangxue)
 - Enh: Support for file aliases in console command 'message' (omnilight)
-- Enh: Sort and Paginiation can now create absolute URLs (cebe)
+- Enh: Sort and Pagination can now create absolute URLs (cebe)
+- Chg #1610: `Html::activeCheckboxList()` and `Html::activeRadioList()` will submit an empty string if no checkbox/radio is selected (qiangxue)
 - Chg: Renamed `yii\jui\Widget::clientEventsMap` to `clientEventMap` (qiangxue)
 - Chg: Renamed `ActiveRecord::getPopulatedRelations()` to `getRelatedRecords()` (qiangxue)
 - Chg: Renamed `attributeName` and `className` to `targetAttribute` and `targetClass` for `UniqueValidator` and `ExistValidator` (qiangxue)

framework/yii/helpers/BaseHtml.php

@@ -1281,7 +1281,8 @@ class BaseHtml
 	 * @param array $options options (name => config) for the checkbox list. The following options are specially handled:
 	 *
 	 * - unselect: string, the value that should be submitted when none of the checkboxes is selected.
-	 *   By setting this option, a hidden input will be generated.
+	 *   You may set this option to be null to prevent default value submission.
+	 *   If this option is not set, an empty string will be submitted.
 	 * - separator: string, the HTML code that separates items.
 	 * - item: callable, a callback that can be used to customize the generation of the HTML code
 	 *   corresponding to a single item in $items. The signature of this callback must be:
@@ -1300,7 +1301,7 @@ class BaseHtml
 		$name = isset($options['name']) ? $options['name'] : static::getInputName($model, $attribute);
 		$selection = static::getAttributeValue($model, $attribute);
 		if (!array_key_exists('unselect', $options)) {
-			$options['unselect'] = '0';
+			$options['unselect'] = '';
 		}
 		if (!array_key_exists('id', $options)) {
 			$options['id'] = static::getInputId($model, $attribute);
@@ -1321,7 +1322,8 @@ class BaseHtml
 	 * @param array $options options (name => config) for the radio button list. The following options are specially handled:
 	 *
 	 * - unselect: string, the value that should be submitted when none of the radio buttons is selected.
-	 *   By setting this option, a hidden input will be generated.
+	 *   You may set this option to be null to prevent default value submission.
+	 *   If this option is not set, an empty string will be submitted.
 	 * - separator: string, the HTML code that separates items.
 	 * - item: callable, a callback that can be used to customize the generation of the HTML code
 	 *   corresponding to a single item in $items. The signature of this callback must be:
@@ -1340,7 +1342,7 @@ class BaseHtml
 		$name = isset($options['name']) ? $options['name'] : static::getInputName($model, $attribute);
 		$selection = static::getAttributeValue($model, $attribute);
 		if (!array_key_exists('unselect', $options)) {
-			$options['unselect'] = '0';
+			$options['unselect'] = '';
 		}
 		if (!array_key_exists('id', $options)) {
 			$options['id'] = static::getInputId($model, $attribute);