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- Yii Tutorial
- Yii - Home
- Yii - Overview
- Yii - Installation
- Yii - Create Page
- Yii - Application Structure
- Yii - Entry Scripts
- Yii - Controllers
- Yii - Using Controllers
- Yii - Using Actions
- Yii - Models
- Yii - Widgets
- Yii - Modules
- Yii - Views
- Yii - Layouts
- Yii - Assets
- Yii - Asset Conversion
- Yii - Extensions
- Yii - Creating Extensions
- Yii - HTTP Requests
- Yii - Responses
- Yii - URL Formats
- Yii - URL Routing
- Yii - Rules of URL
- Yii - HTML Forms
- Yii - Validation
- Yii - Ad Hoc Validation
- Yii - AJAX Validation
- Yii - Sessions
- Yii - Using Flash Data
- Yii - Cookies
- Yii - Using Cookies
- Yii - Files Upload
- Yii - Formatting
- Yii - Pagination
- Yii - Sorting
- Yii - Properties
- Yii - Data Providers
- Yii - Data Widgets
- Yii - ListView Widget
- Yii - GridView Widget
- Yii - Events
- Yii - Creating Event
- Yii - Behaviors
- Yii - Creating a Behavior
- Yii - Configurations
- Yii - Dependency Injection
- Yii - Database Access
- Yii - Data Access Objects
- Yii - Query Builder
- Yii - Active Record
- Yii - Database Migration
- Yii - Theming
- Yii - RESTful APIs
- Yii - RESTful APIs in Action
- Yii - Fields
- Yii - Testing
- Yii - Caching
- Yii - Fragment Caching
- Yii - Aliases
- Yii - Logging
- Yii - Error Handling
- Yii - Authentication
- Yii - Authorization
- Yii - Localization
- Yii - Gii
- Gii – Creating a Model
- Gii – Generating Controller
- Gii – Generating Module
- Yii Useful Resources
- Yii - Quick Guide
- Yii - Useful Resources
- Yii - Discussion
Yii - Creating Event
In this chapter we will see to create an event in Yii. To show events in action, we need data.
Preparing the DB
Step 1 − Create a new database. Database can be prepared in the following two ways.
In the terminal run mysql -u root –p
Create a new database via CREATE DATABASE helloworld CHARACTER SET utf8 COLLATE utf8_general_ci;
Step 2 − Configure the database connection in the config/db.php file. The following configuration is for the system used currently.
<?php return [ 'class' => 'yii\db\Connection', 'dsn' => 'mysql:host=localhost;dbname=helloworld', 'username' => 'vladimir', 'password' => '12345', 'charset' => 'utf8', ]; ?>
Step 3 − Inside the root folder run ./yii migrate/create test_table. This command will create a database migration for managing our DB. The migration file should appear in the migrations folder of the project root.
Step 4 − Modify the migration file (m160106_163154_test_table.php in this case) this way.
<?php use yii\db\Schema; use yii\db\Migration; class m160106_163154_test_table extends Migration { public function safeUp() { $this->createTable("user", [ "id" => Schema::TYPE_PK, "name" => Schema::TYPE_STRING, "email" => Schema::TYPE_STRING, ]); $this->batchInsert("user", ["name", "email"], [ ["User1", "user1@gmail.com"], ["User2", "user2@gmail.com"], ["User3", "user3@gmail.com"], ["User4", "user4@gmail.com"], ["User5", "user5@gmail.com"], ["User6", "user6@gmail.com"], ["User7", "user7@gmail.com"], ["User8", "user8@gmail.com"], ["User9", "user9@gmail.com"], ["User10", "user10@gmail.com"], ["User11", "user11@gmail.com"], ]); } public function safeDown() { $this->dropTable('user'); } } ?>
The above migration creates a user table with these fields: id, name, and email. It also adds a few demo users.
Step 5 − Inside the project root run ./yii migrate to apply the migration to the database.
Step 6 − Now, we need to create a model for our user table. For the sake of simplicity, we are going to use the Gii code generation tool. Open up this url: http://localhost:8080/index.php?r=gii. Then, click the “Start” button under the “Model generator” header. Fill in the Table Name (“user”) and the Model Class (“MyUser”), click the “Preview” button and finally, click the “Generate” button.
![Creating Event Preparing DB](/yii/images/create_model.jpg)
The MyUser model should appear in the models directory.
Create an Event
Assume we want to send an email to the admin whenever a new user registers on our web site.
Step 1 − Modify the models/MyUser.php file this way.
<?php namespace app\models; use Yii; /** * This is the model class for table "user". * * @property integer $id * @property string $name * @property string $email */ class MyUser extends \yii\db\ActiveRecord { const EVENT_NEW_USER = 'new-user'; public function init() { // first parameter is the name of the event and second is the handler. $this->on(self::EVENT_NEW_USER, [$this, 'sendMailToAdmin']); } /** * @inheritdoc */ public static function tableName() { return 'user'; } /** * @inheritdoc */ public function rules() { return [ [['name', 'email'], 'string', 'max' => 255] ]; } /** * @inheritdoc */ public function attributeLabels() { return [ 'id' => 'ID', 'name' => 'Name', 'email' => 'Email', ]; } public function sendMailToAdmin($event) { echo 'mail sent to admin using the event'; } } ?>
In the above code, we define a “new-user” event. Then, in the init() method we attach the sendMailToAdmin function to the “new-user” event. Now, we need to trigger this event.
Step 2 − Create a method called actionTestEvent in the SiteController.
public function actionTestEvent() { $model = new MyUser(); $model->name = "John"; $model->email = "john@gmail.com"; if($model->save()) { $model->trigger(MyUser::EVENT_NEW_USER); } }
In the above code, we create a new user and trigger the “new-user” event.
Step 3 − Now type http://localhost:8080/index.php?r=site/test-event, you will see the following.
![Creating Event](/yii/images/creating_event.jpg)