Question

我想使用带有pdo语句的简单过滤器。以前我使用的是以下代码。

$sql = "select * from cities where 1 ";
$city = $_REQUEST['city_name'];
if($city!=""){
   $sql = $sql. " and name ='".$city."'";

 } 
 $country = $_REQUEST['country_name'];
if($country!=""){
   $sql = $sql. " and country_name ='".$country."'";

 } 

$result= mysql_query($sql);

如果名称或国家/地区名称未来，我想使用过滤器，它应显示所有结果，如果选择名称，则只会出现城市名称结果。如果选择了国家/地区，则国家/地区将适用，否则国家/地区过滤器将不适用。

现在我想和pdo预处理语句一起使用，但我没有得到如何创建它。

$db = new PDO('mysql:host=localhost;dbname=testdb;charset=utf8', 'username', 'password');

Answer 1

试试这个。 $dynamic_fields必须包含键中的mysql字段名称和值中的输入名称：

// mysql_fileld_name => request_key_name
$dynamic_fields = array(
    'name'         => 'city_name',
    'country_name' => 'country_name'
);
$field_values = array();
foreach ($dynamic_fields as $mysql_fname => $input_fname) {
    if (!empty($_REQUEST[ $input_fname ])) {
        $sql .= ' AND `' . $mysql_fname . '` = :' . $mysql_fname; 
        $field_values[ ':' . $mysql_fname ] = $_REQUEST[ $input_fname ];
    }
}

$pdo = new PDO('mysql:host=localhost;dbname=testdb;charset=utf8', 'username', 'password');
$statement = $pdo->prepare($sql);
$statement->execute($field_values);

$result = $statement->fetchAll();

Answer 2

试试这样：

    $arr = array();
    $sql = "select * from cities where 1 ";
    $city = $_REQUEST['city_name'];
    if($city!=""){
        $sql .= " and name = :name";
        $arr[] = ":name => $city";

    }
    $country = $_REQUEST['country_name'];
    if($country!=""){
        $sql .=  " and country_name = :country";
        $arr[] = ":country => $country"; 
    }
    $db = new PDO(DSN, user, password);//set correct db credential 
    $objStaement = $db->prepare($sql);
    //if ($city) $objStaement->bindValue(':name',$city);
    //if ($country) $objStaement->bindValue(':country',$country);
    $objStaement->execute($arr);
    $objStaement->closeCursor();

Answer 3

试试这个:(特别为您编辑）...现在所有绑定都在一个if if / elseif语句中进行。更多的代码，但也许更快一点点。

$name = $_REQUEST['city_name'];
$country_name = $_REQUEST['country_name'];

$dsn = 'mysql:host=localhost;dbname=your_db';
$db_user = 'username';
$db_password = 'password';


$db = new PDO($dsn, $db_user, $db_password);
if ($name && $country_name) {
    $query = 'SELECT * FROM cities WHERE name = :name AND country_name = :country_name';
    $statement = $db->prepare($query);
    $statement->bindValue(':name',$name);
    $statement->bindValue(':country_name',$country_name);
} elseif ($name) { 
    $query = 'SELECT * FROM cities WHERE name = :name';
    $statement = $db->prepare($query);
    $statement->bindValue(':name',$name);
} elseif ($country_name) {
    $query = 'SELECT * FROM cities WHERE country_name = :country_name';
    $statement = $db->prepare($query);
    $statement->bindValue(':country_name',$country_name);
} else {
    $query = 'SELECT * FROM cities';
    $statement = $db->prepare($query);
}

$statement->execute();
$statement->closeCursor();

Answer 4

您可以以同样的方式进行查询。但要执行查询，请使用

$db = new PDO(your information...);
$stmt = $db->prepare($sql);<--your query is $sql
$stmt->execute();

$results = $stmt->fetchAll(PDO::FETCH_ASSOC); //use this to get associative array
$results = $stmt->fetchAll(PDO::FETCH_OBJ); //use this to get objects
$results = $stmt->fetchAll(PDO::FETCH_NUM); //use this for a regular array

有关抓取样式here的更多信息。您可能还想了解参数化查询PDOStatement::bindParam

php pdo prepare语句动态过滤器

4 个答案: