# yii could not find driver
哪些开起来挺简单的东西，真正做起来就未必是看起来的样子了。比如作为一个javaer的我，开始写php代码的时候就掉到了这么一个小坑了，与大家共享
yii框架导入到phpstorm中
config/db.php
<pre><?php
return [
'class' => 'yii\db\Connection',
'dsn' => 'mysql:host=localhost;dbname=yii',
'username' => 'root',
'password' => '',
'charset' => 'utf8'
];</pre>
根据官方手册感觉写完model，写完controller就可以万事大吉，愉快的访问程序了，但天不遂人愿，报了个大大的错误（大脸状）
<pre>{"name":"Database Exception","message":"could not find driver","code":0,"type":"yii\\db\\Exception","file":"E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Connection.php","line":550,"stack-trace":["#0 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Connection.php(864): yii\\db\\Connection->open()","#1 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Connection.php(851): yii\\db\\Connection->getMasterPdo()","#2 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Command.php(219): yii\\db\\Connection->getSlavePdo()","#3 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Command.php(894): yii\\db\\Command->prepare(true)","#4 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Command.php(388): yii\\db\\Command->queryInternal('fetchColumn', 0)","#5 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Query.php(393): yii\\db\\Command->queryScalar()","#6 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\ActiveQuery.php(334): yii\\db\\Query->queryScalar('COUNT(*)', NULL)","#7 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Query.php(300): yii\\db\\ActiveQuery->queryScalar('COUNT(*)', NULL)","#8 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\data\\ActiveDataProvider.php(165): yii\\db\\Query->count('*', NULL)","#9 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\data\\BaseDataProvider.php(147): yii\\data\\ActiveDataProvider->prepareTotalCount()","#10 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\data\\ActiveDataProvider.php(105): yii\\data\\BaseDataProvider->getTotalCount()","#11 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\data\\BaseDataProvider.php(79): yii\\data\\ActiveDataProvider->prepareModels()","#12 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\data\\BaseDataProvider.php(92): yii\\data\\BaseDataProvider->prepare()","#13 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\rest\\Serializer.php(174): yii\\data\\BaseDataProvider->getModels()","#14 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\rest\\Serializer.php(143): yii\\rest\\Serializer->serializeDataProvider(Object(yii\\data\\ActiveDataProvider))","#15 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\rest\\Controller.php(97): yii\\rest\\Serializer->serialize(Object(yii\\data\\ActiveDataProvider))","#16 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\rest\\Controller.php(75): yii\\rest\\Controller->serializeData(Object(yii\\data\\ActiveDataProvider))","#17 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\base\\Controller.php(156): yii\\rest\\Controller->afterAction(Object(yii\\rest\\IndexAction), Object(yii\\data\\ActiveDataProvider))","#18 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\base\\Module.php(454): yii\\base\\Controller->runAction('', Array)","#19 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\web\\Application.php(87): yii\\base\\Module->runAction('navbar', Array)","#20 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\base\\Application.php(375): yii\\web\\Application->handleRequest(Object(yii\\web\\Request))","#21 E:\\phpworkspace\\yii2.09\\web\\index.php(12): yii\\base\\Application->run()","#22 {main}"],"error-info":null,"previous":{"name":"Exception","message":"could not find driver","code":0,"type":"PDOException","file":"E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Connection.php","line":603,"stack-trace":["#0 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Connection.php(603): PDO->__construct('mysql:host=loca...', 'root', '', NULL)","#1 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Connection.php(545): yii\\db\\Connection->createPdoInstance()","#2 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Connection.php(864): yii\\db\\Connection->open()","#3 E:\\phpworkspace\\yii2.09\\vendor\\yiisoft\\yii2\\db\\Connection.php(851): yii\\db\\Connection->getMasterPdo()","</pre>
php还没入门的我，只好借助度娘
原来php在连接数据库的时候还需要打开特定的扩展，就好比java中要导入特定数据库的驱动包一样。原因找到了，动手解决之。
打开php.ini,搜索extension=php_pdo_mysql.dll，将前面的注释打开即可。
另，搜索过程中有些结果还需要打开extension=php_pdo.dll，但是我正在使用php5.6.26版本中并未发现此扩展。