php - Mysql PHP 拒绝用户 '' @'localhost' 访问数据库

Question

使用以下代码，可以成功连接数据库。但是，当尝试使用函数 'executeNonQuery' 执行查询时，出现错误 { Access denied for user ''@'localhost' to database 'photobook' }。用户拥有全部权限，但奇怪的是查询“show grants”不会显示该事实。但是，当在 mysql workbench 的 GUI 中查看用户权限时，它是。可能是什么问题？我什至使用了 root，但查询被拒绝并出现相同的错误。用户可以连接，但不能发出查询。

文件:class.database.php

<?php
    class Database {
        function __construct(){
        }

        public function connect($host, $user, $pass){
            $dbcnct = mysqli_connect($host, $user, $pass);
            if(!$dbcnct){
                die("Couldn't Connect: " . mysql_error());
            }else{
                echo "Connected Successfully";
            }          
        }

        public function disconnect(){
            mysql_close($dbcnct);
            if(!$dbcnct){
                echo "Disconnected Successfully";
            }
        }

        public function executeNonQuery($database, $sql){
            mysql_select_db($database);
            $retval = mysql_query($sql, $dbcnct);
            if(!$retval){
                die("Couldn't Update Data: " . mysql_error());
            }
            echo "Update Successful";
        }
    }
?>


<?php
 include 'class.database.php';
 $db = new Database;
 $db->connect("localhost", "user", "pass"); 
 $userdata=$_GET['data'];
 $index=$_GET['index'];
 echo $index . "<br/>";
 foreach($userdata as $data){
     $sql = "update photobook set photoName='" . $data . "' where photoPosition=" . $index;

    $db->executeNonQuery("photoBook", $sql);
     echo $data . "<br/>";
 }
 $db->disconnect();

?>

Answer 1

您的 $dbcnct 变量只为您使用它的函数定义，而不是为整个类定义。您需要使用类变量，以便您可以在不同的函数中共享变量:

<?php
    class Database 
    {
        public $dbcnct;

        function __construct()
        {
            // Nothing
        }

        public function connect($host, $user, $pass){
            $this->dbcnct = mysqli_connect($host, $user, $pass);
            if(!$this->dbcnct){
                die("Couldn't Connect: " . mysql_error());
            }else{
                echo "Connected Successfully";
            }          
        }

        public function disconnect(){
            mysql_close($this->dbcnct);
            if(!$this->dbcnct){
                echo "Disconnected Successfully";
            }
        }

        public function executeNonQuery($database, $sql){
            mysql_select_db($database);
            $retval = mysql_query($sql, $this->dbcnct);
            if(!$retval){
                die("Couldn't Update Data: " . mysql_error());
            }
            echo "Update Successful";
        }
    }
?>

现在您需要做的就是:

$database->connect("host", "user", "pass");
$database->executeNonQuery("database", "sql");

但首先你需要修复 mysql_ 和 mysqli_ 的混淆 :)