Model类增加只读字段支持

library/think/Model.php

@@ -60,6 +60,8 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
     protected $pk;
     // 数据表字段信息 留空则自动获取
     protected $field = [];
+    // 只读字段
+    protected $readonly = [];
     // 显示属性
     protected $visible = [];
     // 隐藏属性
@@ -663,6 +665,15 @@ abstract class Model implements \JsonSerializable, \ArrayAccess
                 }
             }
 
+            if (!empty($this->readonly)) {
+                // 只读字段不允许更新
+                foreach ($this->readonly as $key => $field) {
+                    if (isset($data[$field])) {
+                        unset($data[$field]);
+                    }
+                }
+            }
+
             if (empty($where) && !empty($this->updateWhere)) {
                 $where = $this->updateWhere;
             }