改进多态关联的关联数据添加

library/think/model/relation/MorphTo.php

@@ -222,6 +222,41 @@ class MorphTo extends Relation
         $result->setAttr(Loader::parseName($relation), $data ?: null);
     }
 
+    /**
+     * 添加关联数据
+     * @access public
+     * @param Model $model       关联模型对象
+     * @return Model
+     */
+    public function associate($model)
+    {
+        $morphKey  = $this->morphKey;
+        $morphType = $this->morphType;
+        $pk        = $model->getPk();
+
+        $this->parent->setAttr($morphKey, $model->$pk);
+        $this->parent->setAttr($morphType, get_class($model));
+        $this->parent->save();
+        return $this;
+    }
+
+    /**
+     * 添加关联数据
+     * @access public
+     * @param Model $model       关联模型对象
+     * @return Model
+     */
+    public function dissociate()
+    {
+        $morphKey  = $this->morphKey;
+        $morphType = $this->morphType;
+
+        $this->parent->setAttr($morphKey, null);
+        $this->parent->setAttr($morphType, null);
+        $this->parent->save();
+        return $this;
+    }
+
     /**
      * 执行基础查询（进执行一次）
      * @access protected