yii2框架使用嵌套集合实现无限极商品分类

1.使用composer安装nested_sets插件composer require creocoder/yii2-nested-sets

2.创建商品分类表的数据迁移

yii migrate/create create_category_table

数据迁移类的内容如下：

$this->createTable('{{%category}}', [

'id'=> $this->primaryKey(),

'tree' => $this->integer()->notNull(),

'lft'=> $this->integer()->notNull(),

'rgt'=> $this->integer()->notNull(),

'depth'=> $this->integer()->notNull(),

'name'=> $this->string()->notNull(),

]);

3.创建商品分类活动记录Category

use creocoder\nestedsets\NestedSetsBehavior;

class Category extends\yii\db\ActiveRecord { publicfunction behaviors() {

return [

'tree'=> [

'class'=>NestedSetsBehavior::className(), 'treeAttribute' => 'tree',

// 'leftAttribute' => 'lft',

// 'rightAttribute' => 'rgt',

// 'depthAttribute' => 'depth',

],

];

}

publicfunction transactions() {

return [

self::SCENARIO_DEFAULT=>self::OP_ALL,

];

}

publicstaticfunction find() {

returnnew Category Query(get_called_class());

} }

4.创建分类查询器Category Query

use creocoder\nestedsets\NestedSetsQueryBehavior; class Category Query extends\yii\db\ActiveQuery { publicfunction behaviors() {

return [

NestedSetsQueryBehavior::className(),

];

} }

5.如何使用

创建一级分类

创建家用电器分类

$category1 =new Category (['name'=>'家用电器']);

$category1 ->makeRoot();

创建出来的树像下面这样

- 家用电器

创建子分类大家电

$category2 =new Category (['name'=>'大家电']); $category2 ->prependTo($category1);

结构如下

- 家用电器

- 大家电

获取所有一级分类

$roots = Category::find()->roots()->all();

获取所有子分类

$leaves = Category::find()->leaves()->all();

获取某分类的所有子孙分类

$category1 =Category::findOne(['name'=>'家用电器']); $leaves =$category1 ->leaves()->all();

获取某节点的所有子分类

$category1 =Category::findOne(['name'=>'家用电器']); $children =$category1 ->children()->all();

获取某分类的第一个子分类

$category1 =Category::findOne(['name'=>'家用电器']); $children =$category1 ->children(1)->all();

获取某分类的所有父分类

$category2=Category::findOne(['name'=>'大家电']); $parents = $category2->parents()->all();

获取某分类的第一个父分类

$category2=Category::findOne(['name'=>'大家电']); $parent = $category2->parents(1)->one();