laravel模型怎么使用（laravel5.1框架model类查询的实现方法）

laravel模型怎么使用

laravel5.1框架model类查询的实现方法

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：

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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：

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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:

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/**  * 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：

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/**  * 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：

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/**  * 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

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/**  * 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()

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/**  * 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开心学习网。

原文链接：https://www.cnblogs.com/dongruiha/p/6276809.html