Php 将代码传输到OOP后将变量传递到mysql查询时出现问题

我正在尝试将我编写的搜索引擎转换为OOP架构

来自数据库连接（sqlconnect1）的相关代码：

    public function query($query){
    $this->stmt = $this->dbh->prepare($query);
    }

    public function bind($param, $value, $type = null){     
        if (is_null($type)) {
            switch (true) {
                case is_int($value):
                    $type = PDO::PARAM_INT;
                    break;
                case is_bool($value):
                    $type = PDO::PARAM_BOOL;
                    break;
                case is_null($value):
                    $type = PDO::PARAM_NULL;
                    break;
                default:
                    $type = PDO::PARAM_STR;
            }
        }

        $this->stmt->bindValue($param, $value, $type);
    }
    public function execute(){
        return $this->stmt->execute();
    }

    public function resultset(){
        //$this->execute();
        return $this->stmt->fetch(PDO::FETCH_ASSOC);
    }

}

protected function __construct(){
    //Make SQL Connection. Then Form Query
    if(isset($_GET['search'])){
        $sqlconnect1 = new sqlconnect1;
        $sqlconnect1->query("SELECT * FROM data1 WHERE address_city LIKE ':get_city'");
        //Bind User Input to Prepared Statement
        $sqlconnect1->bind(':get_city', '$get_city');
        $sqlconnect1->bind(':get_state', '$get_state');
        $sqlconnect1->bind(':get_zip', '$get_zip');
        $sqlconnect1->bind(':get_country', '$get_country');
        $sqlconnect1->bind(':get_category1', '$get_category1');
        $sqlconnect1->bind(':get_name', '$get_name');

        //Execute Query
        $sqlconnect1->execute();
    }

protected function __construct(){
    //Capture User Input
    if(isset($_GET['search'])){
    $this->get_city = filter_var($_GET['query_city'], FILTER_SANITIZE_STRING);
    $this->get_state = filter_var($_GET['query_state'], FILTER_SANITIZE_STRING);
    $this->get_zip = filter_var($_GET['query_zip'], FILTER_SANITIZE_STRING);    
    $this->get_country = filter_var($_GET['query_country'], FILTER_SANITIZE_STRING);
    $this->get_category1 = filter_var($_GET['query_category1'], FILTER_SANITIZE_STRING);
    $this->get_name = filter_var($_GET['query_name'], FILTER_SANITIZE_STRING);
    echo $this->get_city, $this->get_state, $this->get_category1;
    }
    //Validate Data
    if($this->get_state == '' or $this->get_city == '' or $this->get_category1 == ''){
    echo "<center><b>Please, fill in the required fields.</b></center>";
    exit();
    }
}

相关搜索引擎代码：

    public function query($query){
    $this->stmt = $this->dbh->prepare($query);
    }

    public function bind($param, $value, $type = null){     
        if (is_null($type)) {
            switch (true) {
                case is_int($value):
                    $type = PDO::PARAM_INT;
                    break;
                case is_bool($value):
                    $type = PDO::PARAM_BOOL;
                    break;
                case is_null($value):
                    $type = PDO::PARAM_NULL;
                    break;
                default:
                    $type = PDO::PARAM_STR;
            }
        }

        $this->stmt->bindValue($param, $value, $type);
    }
    public function execute(){
        return $this->stmt->execute();
    }

    public function resultset(){
        //$this->execute();
        return $this->stmt->fetch(PDO::FETCH_ASSOC);
    }

}

protected function __construct(){
    //Make SQL Connection. Then Form Query
    if(isset($_GET['search'])){
        $sqlconnect1 = new sqlconnect1;
        $sqlconnect1->query("SELECT * FROM data1 WHERE address_city LIKE ':get_city'");
        //Bind User Input to Prepared Statement
        $sqlconnect1->bind(':get_city', '$get_city');
        $sqlconnect1->bind(':get_state', '$get_state');
        $sqlconnect1->bind(':get_zip', '$get_zip');
        $sqlconnect1->bind(':get_country', '$get_country');
        $sqlconnect1->bind(':get_category1', '$get_category1');
        $sqlconnect1->bind(':get_name', '$get_name');

        //Execute Query
        $sqlconnect1->execute();
    }

protected function __construct(){
    //Capture User Input
    if(isset($_GET['search'])){
    $this->get_city = filter_var($_GET['query_city'], FILTER_SANITIZE_STRING);
    $this->get_state = filter_var($_GET['query_state'], FILTER_SANITIZE_STRING);
    $this->get_zip = filter_var($_GET['query_zip'], FILTER_SANITIZE_STRING);    
    $this->get_country = filter_var($_GET['query_country'], FILTER_SANITIZE_STRING);
    $this->get_category1 = filter_var($_GET['query_category1'], FILTER_SANITIZE_STRING);
    $this->get_name = filter_var($_GET['query_name'], FILTER_SANITIZE_STRING);
    echo $this->get_city, $this->get_state, $this->get_category1;
    }
    //Validate Data
    if($this->get_state == '' or $this->get_city == '' or $this->get_category1 == ''){
    echo "<center><b>Please, fill in the required fields.</b></center>";
    exit();
    }
}

控制器：

    public function query($query){
    $this->stmt = $this->dbh->prepare($query);
    }

    public function bind($param, $value, $type = null){     
        if (is_null($type)) {
            switch (true) {
                case is_int($value):
                    $type = PDO::PARAM_INT;
                    break;
                case is_bool($value):
                    $type = PDO::PARAM_BOOL;
                    break;
                case is_null($value):
                    $type = PDO::PARAM_NULL;
                    break;
                default:
                    $type = PDO::PARAM_STR;
            }
        }

        $this->stmt->bindValue($param, $value, $type);
    }
    public function execute(){
        return $this->stmt->execute();
    }

    public function resultset(){
        //$this->execute();
        return $this->stmt->fetch(PDO::FETCH_ASSOC);
    }

}

protected function __construct(){
    //Make SQL Connection. Then Form Query
    if(isset($_GET['search'])){
        $sqlconnect1 = new sqlconnect1;
        $sqlconnect1->query("SELECT * FROM data1 WHERE address_city LIKE ':get_city'");
        //Bind User Input to Prepared Statement
        $sqlconnect1->bind(':get_city', '$get_city');
        $sqlconnect1->bind(':get_state', '$get_state');
        $sqlconnect1->bind(':get_zip', '$get_zip');
        $sqlconnect1->bind(':get_country', '$get_country');
        $sqlconnect1->bind(':get_category1', '$get_category1');
        $sqlconnect1->bind(':get_name', '$get_name');

        //Execute Query
        $sqlconnect1->execute();
    }

protected function __construct(){
    //Capture User Input
    if(isset($_GET['search'])){
    $this->get_city = filter_var($_GET['query_city'], FILTER_SANITIZE_STRING);
    $this->get_state = filter_var($_GET['query_state'], FILTER_SANITIZE_STRING);
    $this->get_zip = filter_var($_GET['query_zip'], FILTER_SANITIZE_STRING);    
    $this->get_country = filter_var($_GET['query_country'], FILTER_SANITIZE_STRING);
    $this->get_category1 = filter_var($_GET['query_category1'], FILTER_SANITIZE_STRING);
    $this->get_name = filter_var($_GET['query_name'], FILTER_SANITIZE_STRING);
    echo $this->get_city, $this->get_state, $this->get_category1;
    }
    //Validate Data
    if($this->get_state == '' or $this->get_city == '' or $this->get_category1 == ''){
    echo "<center><b>Please, fill in the required fields.</b></center>";
    exit();
    }
}

protectedfunction\uuuu构造（）{
//捕获用户输入
如果（isset（$\u GET['search']））{
$this->get\u city=filter\u var（$\u get['query\u city']，filter\u SANITIZE\u STRING）；
$this->get\u state=filter\u var（$\u get['query\u state']，filter\u SANITIZE\u STRING）；
$this->get\u zip=filter\u var（$\u get['query\u zip']，filter\u SANITIZE\u STRING）；
$this->get\u country=filter\u var（$\u get['query\u country']，filter\u SANITIZE\u STRING）；
$this->get\u category1=filter\u var（$\u get['query\u category1']，filter\u SANITIZE\u STRING）；
$this->get\u name=filter\u var（$\u get['query\u name']，filter\u SANITIZE\u STRING）；
echo$this->get_city，$this->get_state，$this->get_category1；
}
//验证数据
如果（$this->get_state==''或$this->get_city=''或$this->get_category1=''）{
echo“请填写必填字段。”；
退出（）；
}
}

当我搜索时什么也没发生。如果我将

：get_city

替换为实际的城市，一切正常。

您的问题在于：

    $sqlconnect1->query("SELECT * FROM data1 WHERE address_city LIKE ':get_city'");
    //Bind User Input to Prepared Statement
    $sqlconnect1->bind(':get_city', '$get_city');  // <-- your problem

$sqlconnect1->query（“从数据1中选择*地址，如：获取城市”）；
//将用户输入绑定到准备好的语句
$sqlconnect1->bind（':get_city'，'$get_city'）；//我仍然得到同样的结果。如果我回显$get_city，它将返回正确的输入。您更改了什么？我尝试了许多方法。首先，我把报价放在$get_city左右。然后，我用撇号替换了查询周围的引号，并在下面加上引号：get_city there。然后我在每件事上都加上引号。我还尝试了其他10种引号和撇号的组合。