YII-高效

朱雀 2022-05-28 08:14 232阅读 0赞

# 高效 #

## 1、缓存 ##

//获取缓存组件
    $cache = Yii::$app->cache;
    
    //往缓存中写数据
    $cache ->add('key1','hello world');
    $cache ->add('key1','hello world2');
    
        //修改缓存  可以设置
    $cache->set('key1','hello world');
    $cache->set('key1','hello world2');
    
    //读取缓存
    $data = $cache ->get('key1');
    
    //删除数据
    $data = $cache->delete('key1');
    
    //清空数据
    $cache->flush();
    $data = $cache->get('key1');
    
    //缓存有效期
    $cache->add('key','hello world',5);
    $cache->set('key','hello world',5);
    echo $cache->get('key');
    var_dump($data);

### 1、文件缓存 ###

//文件依赖  修改文件缓存失效
     $dependency = new \yii\caching\FileDependency(['fileName'=>'hw.txt']);
    $cache->add('file_key2','hello world',3000, $dependency);

### 2、表达式缓存 ###

先产生缓存，再更改参数、

//表达式依赖   
    view-source:http://www.blog.com/index.php?r=hello/index&name=zhangsan  
    
    //修改参数失效
    $dependency = new \yii\caching\ExpressionDependency(['expression'=>'Yii::$app->request->get("name")']);
    $cache->add('expression_key','hello world',3000,$dependency);
    var_dump($cache->get('expression_key'));

### 3、DB依赖 ###

SQL查询返回的结果发生变化，缓存过期

//DB依赖
    $dependency = new \yii\caching\DbDependency(['sql'=>'SELECT count(*) from yii.orders']);
    $cache->add('db_key','hello world',3000,$dependency);
    var_dump($cache->get('db_key'));

### 4、页面缓存 ###

在控制器中：

#### 一、behavior先于其他操作执行 ####

public function behaviors()
    {
        return [
            [
                'class' => 'yii\filters\PageCache'
            ]
        ];
    }
    
    public function actionIndex()
    {
        echo '3';
    }

#### 二、缓存-文件依赖 ####

public function behaviors()
    {
        return [
            [//文件依赖
                'class' => 'yii\filters\PageCache',
                'duration' => 1000,
                'dependency' => [
                    'class' =>'yii\caching\FileDependency',
                    'fileName' => 'hw.txt'
                ]
            ]
        ];
    }
    
    public function actionIndex()
    {
        echo '4';
    }

#### 三、指定操作缓存 ####

public function behaviors()
    {
        return [
            [//文件依赖
                'class' => 'yii\filters\PageCache',
                'duration' => 1000,
                //'only' => ['index'],
                'only' => ['index','test'],
                'dependency' => [
                    'class' =>'yii\caching\FileDependency',
                    'fileName' => 'hw.txt'
                ]
            ]
        ];
    }
    
    public function actionIndex()
    {
        echo '6';
    }
    
    public function actionTest()
    {
        echo '7';
    }

## 5、HTTP缓存 ##