diff --git a/src/FieldValidation.php b/src/FieldValidation.php
index 79e4474..4d0b45d 100644
--- a/src/FieldValidation.php
+++ b/src/FieldValidation.php
@@ -47,13 +47,17 @@ protected function collectRules()
             }
             // an rule for special scene.
             if (!empty($rule['on'])) {
+                if (!$scene) {
+                    continue;
+                }
                 $sceneList = \is_string($rule['on']) ? array_map('trim', explode(',', $rule['on'])) : (array)$rule['on'];
-                if ($scene && !\in_array($scene, $sceneList, true)) {
+                if (!\in_array($scene, $sceneList, true)) {
                     continue;
                 }
                 unset($rule['on']);
-                $this->_usedRules[] = $rule;
             }
+            
+            $this->_usedRules[] = $rule;
             $field = array_shift($rule);
             if (\is_object($rule[0])) {
                 (yield $field => $rule);
diff --git a/src/ValidationTrait.php b/src/ValidationTrait.php
index 837a121..e183e9f 100644
--- a/src/ValidationTrait.php
+++ b/src/ValidationTrait.php
@@ -360,18 +360,19 @@ protected function collectRules()
             if (!isset($rule[1]) || !$rule[1]) {
                 throw new \InvalidArgumentException('The rule validator is must be setting! position: rule[1].');
             }
-            // global rule.
-            if (empty($rule['on'])) {
-                $this->_usedRules[] = $rule;
-                // only use to special scene.
-            } else {
+            // only use to special scene.
+            if (!empty($rule['on'])) {
+                if (!$scene) {
+                    continue;
+                }
                 $sceneList = \is_string($rule['on']) ? Helper::explode($rule['on']) : (array)$rule['on'];
-                if ($scene && !\in_array($scene, $sceneList, true)) {
+                if (!\in_array($scene, $sceneList, true)) {
                     continue;
                 }
                 unset($rule['on']);
-                $this->_usedRules[] = $rule;
             }
+
+            $this->_usedRules[] = $rule;
             $fields = array_shift($rule);
 
             (yield $fields => $this->prepareRule($rule));
diff --git a/src/ValidatorList.php b/src/ValidatorList.php
index b235209..d22e62b 100644
--- a/src/ValidatorList.php
+++ b/src/ValidatorList.php
@@ -562,14 +562,23 @@ public static function strList($val)
 
     /**
      * 验证字段值是否是一个有效的 JSON 字符串。
-     * @param  string $val
+     * @param mixed $val
+     * @param bool $strict
      * @return bool
      */
-    public static function json($val)
+    public static function json($val, $strict = true)
     {
         if (!$val || (!\is_string($val) && !method_exists($val, '__toString'))) {
             return false;
         }
+
+        $val = (string)$val;
+
+        // must start with: { OR [
+        if ($strict && '[' !== $val[0] && '{' !== $val[0]) {
+            return false;
+        }
+
         json_decode($val);
 
         return json_last_error() === JSON_ERROR_NONE;