* Fix bug#43295.

lib/form/form.class.php

@@ -213,7 +213,7 @@ class form extends fixer
                 if(isset($config['filter'])) $rowData->$field = $this->filter($rowData->$field, $config['filter']);
 
                 /* 检查必填字段。Check required fields. */
-                if(isset($config['required']) && $config['required'] && !isset($rowData->$field))
+                if(isset($config['required']) && $config['required'] && $this->checkEmpty($rowData->$field))
                 {
                     $errorKey  = isset($config['type']) && $config['type'] == 'array' ? "{$field}[{$rowIndex}][]" : "{$field}[{$rowIndex}]";
                     $fieldName = isset($app->lang->{$app->rawModule}->$field) ? $app->lang->{$app->rawModule}->$field : $field;
@@ -228,6 +228,21 @@ class form extends fixer
         $this->dataList = $rowDataList;
     }
 
+    /**
+     * 检查为空。
+     * Empty checking.
+     *
+     * @param  mixed $data
+     * @return bool
+     */
+    public function checkEmpty(mixed $data): bool
+    {
+        if(is_array($data)) return empty($data);
+
+        $data = (string)$data;
+        return empty(strlen($data));
+    }
+
     /**
      * 获取$_POST的数据。
      * Get the data of $_POST.
@@ -267,7 +282,7 @@ class form extends fixer
 
         if(isset($config['filter'])) $data = $this->filter($data, $config['filter']);
 
-        if(isset($config['required']) && $config['required'] && !isset($data))
+        if(isset($config['required']) && $config['required'] && $this->checkEmpty($data))
         {
             $errorKey  = isset($config['type']) && $config['type'] == 'array' ? "{$field}[]" : $field;
             $fieldName = isset($app->lang->{$app->rawModule}->$field) ? $app->lang->{$app->rawModule}->$field : $field;