我有类似这样的东西:
class MyParent {
protected static $object;
protected static $db_fields;
public function delete() {
// delete stuff
}
public static function find_by_id($id = 0) {
global $database;
$result_array = self::find_by_sql("SELECT * FROM " . static::$table_name . " WHERE id=" . $database -> escape_value($id) . " LIMIT 1");
return !empty($result_array) ? array_shift($result_array) : false;
}
public static function find_by_sql($sql = "") {
global $database;
// Do Query
$result_set = $database -> query($sql);
// Get Results
$object_array = array();
while ($row = $database -> fetch_array($result_set)) {
$object_array[] = self::instantiate($row);
}
return $object_array;
}
private static function instantiate($record) {
$object = self::$object;
foreach ($record as $attribute => $value) {
if (self::has_attribute($attribute)) {
$object -> $attribute = $value;
}
}
return $object;
}
}
class TheChild extends MyParent {
protected static $db_fields = array('id', 'name');
protected static $table_name = "my_table";
function __construct() {
self::$object = new TheChild;
}
}
$child= TheChild::find_by_id($_GET['id']);
$child->delete();
我理解到的是:在上面的最后一行代码中,出现了“调用未定义的方法stdClass::delete()”的错误提示。这是继承方面缺少的步骤导致的吗?
stdClass
不是你的类Child
。你确定这是展示错误的确切代码吗? - SirDariusfind_by_sql
,因此我们无法确定find_by_id
返回什么。 - SirDarius