为啥var_dump($re);//什么都不返回， 这是怎么回事？

Question

var_dump($id);$sql='select * from '.$this->table.' where id = ? ';$stmt=$this->pdo->prepare($sql);$stmt->bindParam(1,$pid);$pid=$id;$res=$stmt->execute();$re=$res->fetchall(PDO::FETCH_ASSOC);var_dump($res);//返回bool(true)

Answer 1

$res=$stmt->execute();
$re=$res->fetchall(PDO::FETCH_ASSOC);

改成

$stmt->execute();
$re=$stmt->fetchall(PDO::FETCH_ASSOC);

Answer 2

pdo读取返回的数据库结果只有三种方法,foreach fetch fetchAll.