Question

我正在尝试解决此问题。但是无法做到。请帮忙

我正在尝试查看我的数据库中的所有记录，但得到“致命错误：在非对象上调用成员函数查询（）....”并指向

if ($result = $mysqli->query("SELECT ProductName, Description, Price, Size FROM Products ORDER BY ProductID"))

这是我的完整代码

<?php

                        include('db_connect.php');

**$mysqli = new mysqli("localhost", "netelmbn", "password", "netelmbn");
                       if ($mysqli->connect_errno) {
    printf("Connect failed: %s\n", $mysqli->connect_error);
    exit();
}**


                        if ($result = $mysqli->query("SELECT ProductName, Description, Price, Size FROM Products ORDER BY ProductID"))
                        {

                                if ($result->num_rows > 0)
                                {

                                        echo "<table border='1' cellpadding='10'>";


                                        echo "<tr><th>ProductID</th><th>ProductName</th><th>Description</th><th>Price</th><th>Size</th></tr>";

                                        while ($row = $result_fetch_object())
                                        {

                                              echo "<tr>";
                                                echo "<td>" . $row->ProductID . "</td>";
                                                echo "<td>" . $row->ProductName . "</td>";
                                                echo "<td>" . $row->Description . "</td>";
                                                echo "<td>" . $row->Price . "</td>";
                                                echo "<td>" . $row->Size . "</td>";
                                                echo "<td><a href='records.php?ProductID=" . $row->ProductID . "'>Edit</a></td>";
                                                echo "<td><a href='delete.php?ProductID=" . $row->ProductID . "'>Delete</a></td>";
                                                echo "</tr>";
                                        }
                                        echo "</table>";
                                }
                                else
                                {
                                        echo "No results to display!";
                                }
                        }
                        else
                        {
                                echo "Error: " . $mysqli->error;
                        }


                        $mysqli->close();

                ?>

Answer 1

您需要先实例化$ mysqli对象。您还没有在任何地方打开数据库。

至少你需要这样的东西：

$mysqli = new ClassName( /*some parameters here*/ );

$mysqli->database_open( /* some parameters here */); // or something like this, look at the clas definition

Answer 2

您必须拥有一些数据库类，请检查您的代码。

$mysqli = new Database();
$mysqli->connect();

在执行查询之前

：

$result = $mysqli->query("SELECT ProductName, Description, Price, Size FROM Products ORDER BY ProductID");

如您所见，查询先行，然后是连接资源。＆GT;＆GT;所以，先连接。

在php中出现致命错误

2 个答案: