Question

我继续收到此错误

在.on第134行的非对象上调用成员函数prepare（）。

database.php中

require_once("connect.php");

class Database {
    private $connect;

    function one() {
        $connectdb = $this->connect;
        $forms = new Forms();
        $forms->two();
    }
}

forms.php

require_once("connect.php");

class Forms {
    private $connect;

    function two() {
        $connectdb = $this->connect;

        $construct = $connectdb->prepare("SELECT child.*, parent.name as pname, parent.information as pinformation
            FROM strings child LEFT JOIN strings parent on child.pageid=parent.id WHERE child.sid=:id AND child.submittype='2'");
        $executequery = $construct->execute(array(':id'=>$id));
    }

}

错误发生在查询行上。我的猜测与私有变量$connect有关。我该如何解决这个问题？

Answer 1

您需要首先实例化类Database的新对象并将其分配给$connect：

$this->connect = new Database();

然后你可以使用它：

$connectdb = $this->connect;

Answer 2

Forms类中的Connect不是数据库连接器。

class Forms {
    private $connect;

    public function __construct(){
        $this->connect = Database::getConnection(); // we will define this method below
    }

    function two() {
        $connectdb = $this->connect;

        $construct = $connectdb->prepare("....query....");
        $executequery = $construct->execute(array(':id'=>$id));
    }

}

数据库连接器：

class Database {
    private static $connect;

    public static function getConnection(){
        if (self::$connect){
            return self:$connect;
        }
        self::$connect = new mysqli(...) or what ever connection u use

    }
}

错误：在非对象中调用成员函数prepare（）

2 个答案: