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Correction status：qualified
Teacher's comments：
Collection
Collection
query.php
<?php
class Query{
public $pdo = null;
public $table = '';
public $field = '';
public $where = '';
public $limit = 0;
public function __construct($pdo){
$this->pdo =$pdo;
}
public function table($tablename){
$this -> table =$tablename;
return $this;
}
public function field($fields){
$this -> field =$fields;
return $this;
}
public function where($where){
$this -> where =$where;
return $this;
}
public function limit($limit){
$this -> limit =$limit;
return $this;
}
public function select(){
$fields = empty($this->field) ? '*' :$this -> field;
$where = empty($this->where) ? '' : ' WHERE ' .$this->where;
$limit = empty($this->limit) ? '' : ' LIMIT ' .$this->limit;
$sql = 'SELECT '.$fields.' FROM '.$this->table. $where . $limit;
$stmt = $this->pdo->prepare($sql);
$stmt->execute();
return $stmt->fetchAll(PDO::FETCH_ASSOC);
}
}
?>点击 "运行实例" 按钮查看在线实例
demo06.php
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<meta http-equiv="X-UA-Compatible" content="ie=edge">
<title>Document</title>
</head>
<body>
<?php
require 'Query.php';
class Db{
protected static $pdo = null;
protected static function connection(){
self::$pdo = new PDO('mysql:host=127.0.0.1;dbname=php','root','root');
}
public static function __callStatic($name,$arguments){
self::connection();
$query = new Query(self::$pdo);
return call_user_func_array([$query,$name],[$arguments[0]]);
}
}
$staffs = Db::table('staff')
->field('id,name,position,mobile')
->where('id > 5')
->limit(5)
->select();
foreach($staffs as $staff){
print_r($staff);
echo '<br/>';
}
?>
</body>
</html>点击 "运行实例" 按钮查看在线实例
