Yii2数据提供者 dataProvider

程序人生
$dataProvider = new ActiveDataProvider([
    'query' => $query,                  // 如何来取得数据
    'pagination' => ['pageSize'=>5],    // pagination 用于分页
    'sort'  => [                        // sort 用于排序
        'defaultOrder' => [
            'id' => SORT_DESC,          // defaultOrder 指定默认排序字段
        ],
        'attributes' => ['id','title'], // attribute 指定那几个字段可以用来排序
    ],
]);
如果需要打印原生sql,使用如下方法:
echo $query ->createCommand()->getRawSql();

$dataProvider->query->each() //获取 $dataProvider 所有记录;
$dataProvider->getModels() // 获取当前页的数据,以数组的方式返回
由于 $dataProvider->getModels() 获取的数据是当前页的,如果在导出的时候需要导出所有记录而不是当前页,且又使用的是 SqlDataProvider ,那么就可以在控制器文件中在重新设置一下分页,将值设置的特别大,就可以模拟为不分页了。
use yii\db\Pagination;

$dataProvider = $searchModel->search(\Yii::$app->request->getQueryParams());
$dataProvider->setPagination(new Pagination([
     'defaultPageSize' => 10000,
     'pageSizeLimit' => [1, 10000]
]));

二、Yii的数据提供者类都包含:

如果需要使用 UNION 联合多张表查询,且查询中还可能包含 关联查询(join)的时候,使用 SqlDataProvider 来实现如下:

<?php
namespace organize\models;

use Yii;
use yii\base\Model;
use standard\models\Country;
use organize\models\User;
use yii\db\Expression;
use yii\data\SqlDataProvider;

class CountrySearch extends Country
{
    /**
     * @inheritdoc
     */
    public function rules()
    {
        return [
            [['country_id', 'created_at', 'updated_at', 'is_delete'], 'integer'],
            [[ 'country_name','remarks'], 'safe'],
        ];
    }

    /**
     * @inheritdoc
     */
    public function scenarios()
    {
        // bypass scenarios() implementation in the parent class
        return Model::scenarios();
    }

    /**
     * Creates data provider instance with search query applied
     *
     * @param array $params
     *
     * @return SqlDataProvider
     */
    public function search($params)
    {
        $query = self::find()
            ->select(['country_id AS unique_id','country_name','created_at'])
            ->addSelect(new Expression("'country' AS table_name"));  // 查询一个常量

        $this->load($params);

        // grid filtering conditions
        $query->andFilterWhere([
            'country_id' => $this->country_id,
            'created_at' => $this->created_at,
            'updated_at' => $this->updated_at,
            'is_delete' => $this->is_delete,
        ]);

        $query->andFilterWhere(['like', 'country_name', $this->country_name])
            ->andFilterWhere(['like', 'remarks', $this->remarks]);
        $query->from('standard.country');  // 有多个库名的时候使用


        $userQuery = User::find();
        $userQuery->innerJoin('organize.org_auth_assignment','org_user.id=org_auth_assignment.user_id')
            ->select(['id AS unique_id','realname','sex','dept_id','mobile','email','qq','org_auth_assignment.name as role','org_user.created_at'])
            ->addSelect(new Expression("'org_user' AS table_name"));

        $userQuery->andFilterWhere(['like', 'realname', $this->realname])
            ->andFilterWhere(['like', 'sex', $this->sex])
            ->andFilterWhere(['=', 'org_auth_assignment.name', $this->role])
            ->andFilterWhere(['like', 'mobile', $this->mobile])
            ->andFilterWhere(['like', 'email', $this->email])
            ->andFilterWhere(['like', 'qq', $this->qq]);
        $userQuery->from('organize.org_user');

        $query->union($userQuery,true);  // 联合查询

        $sql = $query->createCommand()->rawSql;  // 生成一条不带分页的 sql
        $dataProvider = new SqlDataProvider([
            'sql' => $sql,
            'totalCount' => $query->count(),
            'sort' => false,
            'pagination' => [
                'pageSize' => 20,
            ],
        ]);

        if (!$this->validate()) {
            // uncomment the following line if you do not want to return any records when validation fails
            // $query->where('0=1');
            return $dataProvider;
        }

        //echo $query->createCommand()->getRawSql();
        return $dataProvider;
    }
}
// 最后的 $dataProvider 渲染到页面后,用 ArrayHelper() 即可获取对应的值
关于 $dataProvider 更详细的内容,请参考官网:http://www.yiichina.com/doc/guide/2.0/output-data-providers
Tags: Yii2 DataProvider
转自:https://www.cnblogs.com/chrdai/p/7966640.html
  • 还没有评论,沙发等你来抢
*         

正在加载验证码......