如何在PHP中动态绑定mysqli bind_param参数？

php arrays bind prepared-statement mysqli

2022-08-30 20:42:26

我一直在学习使用准备好的和绑定的语句进行sql查询，到目前为止，我已经提出了这个，它工作正常，但是当涉及多个参数或不需要参数时，它根本不是动态的，

public function get_result($sql,$parameter)
    {
        # create a prepared statement
    $stmt = $this->mysqli->prepare($sql);

        # bind parameters for markers
    # but this is not dynamic enough...
        $stmt->bind_param("s", $parameter);

        # execute query 
        $stmt->execute();

    # these lines of code below return one dimentional array, similar to mysqli::fetch_assoc()
        $meta = $stmt->result_metadata(); 

        while ($field = $meta->fetch_field()) { 
            $var = $field->name; 
            $$var = null; 
            $parameters[$field->name] = &$$var; 
        }

        call_user_func_array(array($stmt, 'bind_result'), $parameters); 

        while($stmt->fetch()) 
        { 
            return $parameters;
            //print_r($parameters);      
        }


        # close statement
        $stmt->close();
    }

这就是我如何称呼对象类，

$mysqli = new database(DB_HOST,DB_USER,DB_PASS,DB_NAME);
$output = new search($mysqli);

有时我不需要传入任何参数，

$sql = "
SELECT *
FROM root_contacts_cfm
";

print_r($output->get_result($sql));

有时我只需要一个参数，

$sql = "
SELECT *
FROM root_contacts_cfm
WHERE root_contacts_cfm.cnt_id = ?
ORDER BY cnt_id DESC
";

print_r($output->get_result($sql,'1'));

有时我只需要多个参数，

$sql = "
SELECT *
FROM root_contacts_cfm
WHERE root_contacts_cfm.cnt_id = ?
AND root_contacts_cfm.cnt_firstname = ?
ORDER BY cnt_id DESC
";

print_r($output->get_result($sql,'1','Tk'));

所以，我相信这条线对于上面的动态任务来说不够动态，

$stmt->bind_param("s", $parameter);

为了动态构建bind_param，我在网上的其他帖子中发现了这一点。

call_user_func_array(array(&$stmt, 'bind_params'), $array_of_params);

我试图修改 php.net 的一些代码，但我一无所获，

if (strnatcmp(phpversion(),'5.3') >= 0) //Reference is required for PHP 5.3+ 
    { 
        $refs = array(); 
        foreach($arr as $key => $value) 
            $array_of_param[$key] = &$arr[$key]; 

       call_user_func_array(array(&$stmt, 'bind_params'), $array_of_params);

     }

为什么？任何想法，我怎么能使它工作？

或者也许有更好的解决方案？

答案 1

使用 PHP 5.6，您可以在解包运算符（）的帮助下轻松完成此操作，并使用 get_result（）而不是 bind_result（）...$var

public function get_result($sql,$types = null,$params = null) {
    $stmt = $this->mysqli->prepare($sql);
    $stmt->bind_param($types, ...$params);

    if(!$stmt->execute()) return false;
    return $stmt->get_result();

}

例：

$mysqli = new database(DB_HOST,DB_USER,DB_PASS,DB_NAME);
$output = new search($mysqli);


$sql = "SELECT * FROM root_contacts_cfm WHERE root_contacts_cfm.cnt_id = ?
        AND root_contacts_cfm.cnt_firstname = ?
        ORDER BY cnt_id DESC";

$res = $output->get_result($sql, 'ss',array('1','Tk'));
while($row = res->fetch_assoc()){
   echo $row['fieldName'] .'<br>';
}

答案 2

找到了mysqli的答案：

public function get_result($sql,$types = null,$params = null)
    {
        # create a prepared statement
        $stmt = $this->mysqli->prepare($sql);

        # bind parameters for markers
        # but this is not dynamic enough...
        //$stmt->bind_param("s", $parameter);

        if($types&&$params)
        {
            $bind_names[] = $types;
            for ($i=0; $i<count($params);$i++) 
            {
                $bind_name = 'bind' . $i;
                $$bind_name = $params[$i];
                $bind_names[] = &$$bind_name;
            }
            $return = call_user_func_array(array($stmt,'bind_param'),$bind_names);
        }

        # execute query 
        $stmt->execute();

        # these lines of code below return one dimentional array, similar to mysqli::fetch_assoc()
        $meta = $stmt->result_metadata(); 

        while ($field = $meta->fetch_field()) { 
            $var = $field->name; 
            $$var = null; 
            $parameters[$field->name] = &$$var; 
        }

        call_user_func_array(array($stmt, 'bind_result'), $parameters); 

        while($stmt->fetch()) 
        { 
            return $parameters;
            //print_r($parameters);      
        }


        # the commented lines below will return values but not arrays
        # bind result variables
        //$stmt->bind_result($id); 

        # fetch value
        //$stmt->fetch(); 

        # return the value
        //return $id; 

        # close statement
        $stmt->close();
    }

然后：

$mysqli = new database(DB_HOST,DB_USER,DB_PASS,DB_NAME);
$output = new search($mysqli);

$sql = "
SELECT *
FROM root_contacts_cfm
ORDER BY cnt_id DESC
";
print_r($output->get_result($sql));

$sql = "
SELECT *
FROM root_contacts_cfm
WHERE root_contacts_cfm.cnt_id = ?
ORDER BY cnt_id DESC
";

print_r($output->get_result($sql,'s',array('1')));

$sql = "
SELECT *
FROM root_contacts_cfm
WHERE root_contacts_cfm.cnt_id = ?
AND root_contacts_cfm.cnt_firstname = ?
ORDER BY cnt_id DESC
";

print_r($output->get_result($sql, 'ss',array('1','Tk')));

mysqli在谈到这一点时是如此蹩脚。我想我应该迁移到PDO！