Yii中Model(模型)的创建及使用方法

'db'=>array(
  'connectionString' => 'mysql:host=localhost;dbname=oss','emulatePrepare' => true,'username' => 'root','password' => 'hahaha','charset' => 'utf8',//表前缀
  'tablePrefix'=>"oss_"
),

//显示日志信息,包括sql的查询信息
array(
  'class'=>'CWebLogRoute',),

class Post extends CActiveRecord
{
public static function model($className=__CLASS__)
{
return parent::model($className);
}
public function tableName()
{
return '{{post}}';
}
public function primaryKey()
{
return 'id';
// return array('pk1','pk2');
}
}

$post=new Post;
$post->title='sample post';
$post->content='content for the sample post';
$post->create_time=time();
$post->save();

// find the first row satisfying the specified condition
$post=Post::model()->find($condition,$params);
// find the row with the specified primary key
$post=Post::model()->findByPk($postID,$condition,$params);
// find the row with the specified attribute values
$post=Post::model()->findByAttributes($attributes,$params);
// find the first row using the specified SQL statement
$post=Post::model()->findBySql($sql,$params);
$criteria=new CDbCriteria;
$criteria->select='title'; // only select the 'title' column
$criteria->condition='postID=:postID';
$criteria->params=array(':postID'=>10);
$post=Post::model()->find($criteria);
$post=Post::model()->find(array(
'select'=>'title','condition'=>'postID=:postID','params'=>array(':postID'=>10),));
// find all rows satisfying the specified condition
$posts=Post::model()->findAll($condition,$params);
// find all rows with the specified primary keys
$posts=Post::model()->findAllByPk($postIDs,$params);
// find all rows with the specified attribute values
$posts=Post::model()->findAllByAttributes($attributes,$params);
// find all rows using the specified SQL statement
$posts=Post::model()->findAllBySql($sql,$params);
// get the number of rows satisfying the specified condition
$n=Post::model()->count($condition,$params);
// get the number of rows using the specified SQL statement
$n=Post::model()->countBySql($sql,$params);
// check if there is at least a row satisfying the specified condition
$exists=Post::model()->exists($condition,$params);

// update the rows matching the specified condition
Post::model()->updateAll($attributes,$params);
// update the rows matching the specified condition and primary key(s)
Post::model()->updateByPk($pk,$attributes,$params);
// update counter columns in the rows satisfying the specified conditions
Post::model()->updateCounters($counters,$params);

$post=Post::model()->findByPk(10); // assuming there is a post whose ID is 10
$post->delete();
// delete the rows matching the specified condition
Post::model()->deleteAll($condition,$params);
// delete the rows matching the specified condition and primary key(s)
Post::model()->deleteByPk($pk,$params);

$model=Post::model();
$transaction=$model->dbConnection->beginTransaction();
try
{
// find and save are two steps which may be intervened by another request
// we therefore use a transaction to ensure consistency and integrity
$post=$model->findByPk(10);
$post->title='new post title';
$post->save();
$transaction->commit();
}
catch(Exception $e)
{
$transaction->rollBack();
}

class LoginForm extends CFormModel
{
public $username;
public $password;
public $rememberMe=false;
}

class LoginForm extends CFormModel
{
public $username;
public $password;
public $rememberMe=false;
private $_identity;
public function rules()
{
return array(
array('username,password','required'),array('rememberMe','boolean'),array('password','authenticate'),);
}
public function authenticate($attribute,$params)
{
if(!$this->hasErrors()) // we only want to authenticate when no input errors
{
$this->_identity=new UserIdentity($this->username,$this->password);
if(!$this->_identity->authenticate())
$this->addError('password','Incorrect password.');
}
}
}

// username is required
array('username',// username must be between 3 and 12 characters
array('username','length','min'=>3,'max'=>12),// when in register scenario,password must match password2
array('password','compare','compareAttribute'=>'password2','on'=>'register'),// when in login scenario,password must be authenticated
array('password','authenticate','on'=>'login'),

$model=new LoginForm;
if(isset($_POST['LoginForm']))
$model->attributes=$_POST['LoginForm'];

foreach($_POST['LoginForm'] as $name=>$value)
{
if($name is a safe attribute)
$model->$name=$value;
}

array('username,'required','on'=>'login,register'),array('email',

// in login scenario
$model=new User('login');
if(isset($_POST['User']))
$model->attributes=$_POST['User'];
// in register scenario
$model=new User('register');
if(isset($_POST['User']))
$model->attributes=$_POST['User'];