'log'=>array(
    'class'=>'CLogRouter',
    'routes'=>array(
      array(
        'class'=>'CFileLogRoute',
        'levels'=>'error, warning',

      ),
              // 下面顯示頁(yè)面日志 
              array( 
               'class'=>'CWebLogRoute', 
               'levels'=>'trace',  //級(jí)別為trace 
               'categories'=>'system.db.*' //只顯示關(guān)于數(shù)據(jù)庫(kù)信息,包括數(shù)據(jù)庫(kù)連接,數(shù)據(jù)庫(kù)執(zhí)行語句 
              ), 
      // uncomment the following to show log messages on web pages
      /*
      array(
        'class'=>'CWebLogRoute',
      ),
      */
    ),
  ),

 <?php

/**
 * author   : forecho <caizhenghai@gmail.com>
 * createTime : 2015/12/22 18:13
 * description:
 */
namespace common\components;

use Yii;
use yii\helpers\FileHelper;

class FileTarget extends \yii\log\FileTarget
{
  /**
   * @var bool 是否啟用日志前綴 (@app/runtime/logs/error/20151223_app.log)
   */
  public $enableDatePrefix = false;

  /**
   * @var bool 啟用日志等級(jí)目錄
   */
  public $enableCategoryDir = false;

  private $_logFilePath = '';

  public function init()
  {
    if ($this->logFile === null) {
      $this->logFile = Yii::$app->getRuntimePath() . '/logs/app.log';
    } else {
      $this->logFile = Yii::getAlias($this->logFile);
    }
    $this->_logFilePath = dirname($this->logFile);

    // 啟用日志前綴
    if ($this->enableDatePrefix) {
      $filename = basename($this->logFile);
      $this->logFile = $this->_logFilePath . '/' . date('Ymd') . '_' . $filename;
    }

    if (!is_dir($this->_logFilePath)) {
      FileHelper::createDirectory($this->_logFilePath, $this->dirMode, true);
    }

    if ($this->maxLogFiles < 1) {
      $this->maxLogFiles = 1;
    }
    if ($this->maxFileSize < 1) {
      $this->maxFileSize = 1;
    }

  }
}

'components' => [
  'log' => [
    'traceLevel' => YII_DEBUG ? 3 : 0,
    'targets' => [
      /**
       * 錯(cuò)誤級(jí)別日志：當(dāng)某些需要立馬解決的致命問題發(fā)生的時(shí)候，調(diào)用此方法記錄相關(guān)信息。
       * 使用方法：Yii::error()
       */
      [
        'class' => 'common\components\FileTarget',
        // 日志等級(jí)
        'levels' => ['error'],
        // 被收集記錄的額外數(shù)據(jù)
        'logVars' => ['_GET', '_POST', '_FILES', '_COOKIE', '_SESSION','_SERVER'],
        // 指定日志保存的文件名
        'logFile' => '@app/runtime/logs/error/app.log',
        // 是否開啟日志 (@app/runtime/logs/error/20151223_app.log)
        'enableDatePrefix' => true,
        'maxFileSize' => 1024 * 1,
        'maxLogFiles' => 100,
      ],
      /**
       * 警告級(jí)別日志：當(dāng)某些期望之外的事情發(fā)生的時(shí)候，使用該方法。
       * 使用方法：Yii::warning()
       */
      [
        'class' => 'common\components\FileTarget',
        // 日志等級(jí)
        'levels' => ['warning'],
        // 被收集記錄的額外數(shù)據(jù)
        'logVars' => ['_GET', '_POST', '_FILES', '_COOKIE', '_SESSION','_SERVER'],
        // 指定日志保存的文件名
        'logFile' => '@app/runtime/logs/warning/app.log',
        // 是否開啟日志 (@app/runtime/logs/warning/20151223_app.log)
        'enableDatePrefix' => true,
        'maxFileSize' => 1024 * 1,
        'maxLogFiles' => 100,
      ],
      /**
       * info 級(jí)別日志：在某些位置記錄一些比較有用的信息的時(shí)候使用。
       * 使用方法：Yii::info()
       */
      [
        'class' => 'common\components\FileTarget',
        // 日志等級(jí)
        'levels' => ['info'],
        // 被收集記錄的額外數(shù)據(jù)
        'logVars' => ['_GET', '_POST', '_FILES', '_COOKIE', '_SESSION','_SERVER'],
        // 指定日志保存的文件名
        'logFile' => '@app/runtime/logs/info/app.log',
        // 是否開啟日志 (@app/runtime/logs/info/20151223_app.log)
        'enableDatePrefix' => true,
        'maxFileSize' => 1024 * 1,
        'maxLogFiles' => 100,
      ],
      /**
       * trace 級(jí)別日志：記錄關(guān)于某段代碼運(yùn)行的相關(guān)消息。主要是用于開發(fā)環(huán)境。
       * 使用方法：Yii::trace()
       */
      [
        'class' => 'common\components\FileTarget',
        // 日志等級(jí)
        'levels' => ['trace'],
        // 被收集記錄的額外數(shù)據(jù)
        'logVars' => ['_GET', '_POST', '_FILES', '_COOKIE', '_SESSION','_SERVER'],
        // 指定日志保存的文件名
        'logFile' => '@app/runtime/logs/trace/app.log',
        // 是否開啟日志 (@app/runtime/logs/trace/20151223_app.log)
        'enableDatePrefix' => true,
        'maxFileSize' => 1024 * 1,
        'maxLogFiles' => 100,
      ],
    ],
  ],
],

Yii::log($message,CLogger::LEVEL_ERROR,$category);

/**
 * Initializes this application component.
 * This method is required by the IApplicationComponent interface.  
*/
 public function init(){ 
  parent::init(); 
  foreach($this->_routes as $name=>$route) { 
    $route=Yii::createComponent($route);  
    $route->init();  
    $this->_routes[$name]=$route; 
  } 
  Yii::getLogger()->attachEventHandler('onFlush',array($this,'collectLogs')); 
  Yii::app()->attachEventHandler('onEndRequest',array($this,'processLogs'));}

 if($this->hasEventHandler('onEndRequest')) {
 $this->onEndRequest(new CEvent($this));
 }

 $logs=$logger->getLogs($this->levels,$this->categories); //執(zhí)行過濾，只得到期望信息

 CFileLogRoute::processLogs($logs);

'preload'=>array('log'),
components => array(
       'log'=>array(
         'class'=>'CLogRouter',
         'routes'=>array(
          array(
            'class'=>'CFileLogRoute',
            'levels'=>'error, warning,trace',
          ),
         )
        ）
       ）

 if($this->hasEventHandler('onEndRequest')) {
  $this->onEndRequest(new CEvent($this));
 }

'log'=>array(
'class'=>'CLogRouter',
'routes'=>array(
array(
'class'=>'CFileLogRoute',
'levels'=>'error, warning,trace',
),
array(
'class' => 'myEmailLogRoute',
'levels' => 'error', #所有異常的錯(cuò)誤級(jí)別均為error, 
'categories' => 'exception.CDbException', #數(shù)據(jù)庫(kù)產(chǎn)生錯(cuò)誤時(shí)，均會(huì)產(chǎn)生CDbException異常。
'host' => 'mail.163.com',
'port' => 25,
'user' => 'jeff_yu',
'password' => 'you password',
'timeout' => 30,
'emails' => 'jeff_yu@gmail.com', #日志接收人。
'sentFrom' => 'jeff_yu@gmail.com',
),