laravel5.1框架model类查询的实现方法

时间:2021-05-26

laravel框架model类查询实现:

User::where(['uid'=8])->get();

User类继承自Model类:Illuminate\Database\Eloquent\Model

当User类静态调用where方法时,自动调用了Model里的魔术方法:

public static function __callStatic($method, $parameters){ $instance = new static; //这里的$instance就是User类的实例对象 return call_user_func_array([$instance, $method], $parameters);}

相当于调用了user对象的where方法,这时就又调用了魔术方法:

public function __call($method, $parameters){ if (in_array($method, ['increment', 'decrement'])) { return call_user_func_array([$this, $method], $parameters); } $query = $this->newQuery(); //返回Illuminate\Database\Eloquent\Builder对象 return call_user_func_array([$query, $method], $parameters);}

相当于调用Illuminate\Database\Eloquent\Builder对象里的where方法和get方法,这两个方法里其实

其实是封装调用了Illuminate\Database\Query\Builder对象里的where方法和get方法->get方法里调用了runselect方法

runSelect方法:

/** * Run the query as a "select" statement against the connection. * * @return array */protected function runSelect(){ return $this->connection->select($this->toSql(), $this->getBindings(), ! $this->useWritePdo); //调用connection 对象的select方法}

再看connection对象是怎么传到Illuminate\Database\Eloquent\Builder类实例里的:

Model类的newQuery方法:

/** * Get a new query builder for the model's table. * * @return \Illuminate\Database\Eloquent\Builder */public function newQuery(){ $builder = $this->newQueryWithoutScopes(); return $this->applyGlobalScopes($builder);}

Model类的newQueryWithoutScopes方法:

/** * Get a new query builder that doesn't have any global scopes. * * @return \Illuminate\Database\Eloquent\Builder|static */public function newQueryWithoutScopes(){ $builder = $this->newEloquentBuilder( $this->newBaseQueryBuilder() //这个方法返回 ); // Once we have the query builders, we will set the model instances so the // builder can easily access any information it may need from the model // while it is constructing and executing various queries against it. return $builder->setModel($this)->with($this->with);}

Model类的newBaseQueryBuilder方法实现

/** * Get a new query builder instance for the connection. * * @return \Illuminate\Database\Query\Builder */protected function newBaseQueryBuilder(){ $conn = $this->getConnection(); \\连接数据库并返回connection对象 $grammar = $conn->getQueryGrammar(); return new QueryBuilder($conn, $grammar, $conn->getPostProcessor()); //Illuminate\Database\Query\Builder}

Model类的$resolver属性(连接解析器)的设定是通过

Illuminate\Database\DatabaseServiceProvider 里的boot方法设置的

这样Model类的getConnection方法实际调用的DatabaseManager类的connection方法,返回connection类实例

如何创建的数据库连接:

Model类getConnection方法->DatabaseManager类connection方法->

->ConnectionFactory类的createSingleConnection()

/** * Create a single database connection instance. * * @param array $config * @return \Illuminate\Database\Connection */protected function createSingleConnection(array $config){ //创建连接器对象并连接数据库返回pdo对象 $pdo = $this->createConnector($config)->connect($config); //传入PDO对象、并返回connection对象,connection对象负责查询数据库 return $this->createConnection($config['driver'], $pdo, $config['database'], $config['prefix'], $config); }

以上这篇laravel5.1框架model类查询的实现方法就是小编分享给大家的全部内容了,希望能给大家一个参考,也希望大家多多支持。

声明:本页内容来源网络,仅供用户参考;我单位不保证亦不表示资料全面及准确无误,也不保证亦不表示这些资料为最新信息,如因任何原因,本网内容或者用户因倚赖本网内容造成任何损失或损害,我单位将不会负任何法律责任。如涉及版权问题,请提交至online#300.cn邮箱联系删除。

相关文章