The example in this article describes how Yii2 implements the search function for related fields. Share it with everyone for your reference, the details are as follows:

There are two tables here, the table structure is as follows, companies_compay_id is the foreign key

yii2advanced.branches table:

branch_id:int(11)
companies_company_id:int(11)
branch_name :varchar(100)
branch_address:varchar(255)
branch_created_date:datetime
branch_status:enum('active','inactive')

yii2advanced.companies table:

company_id:int(11)
company_name:varchar(100 )
company_email:varchar(100)
company_address:varchar(255)
logo:varchar(200)
company_start_date:datetime
company_create_date:datetime
company_status:enum('active','inactive')

In the above table, You can use companiesCompany.company_name to get the company name, but this does not support search.

To support the search function, you need to add the following code to the index view of branches:

<?= GridView::widget([
  &#39;dataProvider&#39; => $dataProvider,
  &#39;filterModel&#39; => $searchModel,
  &#39;columns&#39; => [
    [&#39;class&#39; => &#39;yii\grid\SerialColumn&#39;],
    //添加的代碼開(kāi)始
    [
      &#39;label&#39;=>&#39;公司名&#39;,
      &#39;attribute&#39;=>&#39;companies_company_id&#39;,
      &#39;value&#39;=>&#39;companiesCompany.company_name&#39;
    ],
     //添加的代碼結(jié)束
    &#39;companiesCompany.company_name&#39;,
    // &#39;branch_id&#39;,
    // &#39;companies_company_id&#39;,
    &#39;branch_name&#39;,
    &#39;branch_address&#39;,
    &#39;branch_created_date&#39;,
    // &#39;branch_status&#39;,
    [&#39;class&#39; => &#39;yii\grid\ActionColumn&#39;],
  ],
]); ?>

Then modify SearchBranches.php

Modify the rules method as:

public function rules()
{
  return [
    [['branch_id'], 'integer'],
    [['branch_name', 'branch_address', 'branch_created_date', 'branch_status','companies_company_id'], 'safe'],
  ];
}

Modify the search method:

public function search($params)
{
  $query = Branches::find();
  $dataProvider = new ActiveDataProvider([
    'query' => $query,
  ]);
  $this->load($params);
  if (!$this->validate()) {
    // uncomment the following line if you do not want to any records when validation fails
    // $query->where('0=1');
    return $dataProvider;
  }
  // 添加下面這行代碼
  $query->joinWith('companiesCompany');
  $query->andFilterWhere([
    'branch_id' => $this->branch_id,
  //  'companies_company_id' => $this->companies_company_id,
    'branch_created_date' => $this->branch_created_date,
  ]);
  $query->andFilterWhere(['like', 'branch_name', $this->branch_name])
    ->andFilterWhere(['like', 'branch_address', $this->branch_address])
    ->andFilterWhere(['like', 'branch_status', $this->branch_status])
     // 添加下面這行代碼
    ->andFilterWhere(['like', 'companies.company_name', $this->companies_company_id]);
  return $dataProvider;

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