使用 HTML 和 MYSQL PHP 的 CRUD 操作

Question

注意：未定义变量：db in C:\xampp\htdocs\xampp\index1.php on line 32

Warning: mysqli_query() expects parameter 1 to be mysqli, null given in C:\xampp\htdocs\xampp\index1.php on line 32
Warning: mysqli_fetch_array() expects parameter 1 to be mysqli_result, null given in C:\xampp\htdocs\xampp\index1.php on line 43 Notice: Undefined variable: update in C:\xampp\htdocs\xampp\index1.php on line 69

<!DOCTYPE html>
<html>
<head>
    <title>CRUD: CReate, Update, Delete PHP MySQL</title>
</head>
<body>
<?php if (isset($_SESSION['message'])): ?>

    <div class="msg">
        <?php
            echo $_SESSION['message'];
            unset($_SESSION['message']);
            ?>
                </div>
            <?php endif?>
            <?php
            if (isset($_GET['edit'])) {
                $id = $_GET['edit'];
                $update = true;
                $record = mysqli_query($db, "SELECT * FROM info WHERE id=$id");

                if (count($record) == 1) {
                    $n = mysqli_fetch_array($record);
                    $name = $n['name'];
                    $address = $n['address'];
                }
            }
        ?>

<?php

$results = mysqli_query($db, "SELECT * FROM info");?>

<table>
    <thead>
        <tr>
            <th>Name</th>
            <th>Address</th>
            <th colspan="2">Action</th>
        </tr>
    </thead>

    <?php while ($row = mysqli_fetch_array($results)) {?>
        <tr>
            <td><?php echo $row['name']; ?></td>
            <td><?php echo $row['address']; ?></td>
            <td>
                <a href="index.php?edit=<?php echo $row['id']; ?>" class="edit_btn" >Edit</a>
            </td>
            <td>
                <a href="server.php?del=<?php echo $row['id']; ?>" class="del_btn">Delete</a>
            </td>
        </tr>
    <?php }?>
</table>

<form>
    <form method="post" action="php_code.php" >
<input type="hidden" name="id" value="<?php echo $id; ?>">
        <div class="input-group">
            <label>Name</label>
            <input type="text" name="name" value="">
        </div>
        <div class="input-group">
            <label>Address</label>
            <input type="text" name="address" value="">
        </div>
        <div class="input-group">
            <?php if ($update == true): ?>
    <button class="btn" type="submit" name="update" style="background: #556B2F;" >update</button>
<?php else: ?>
    <button class="btn" type="submit" name="save" >Save</button>
<?php endif?>
        </div>
    </form>
</body>
</html>
                      2ND FILE

<?php
session_start();
$db = mysqli_connect('localhost', 'root', '', 'crud');

$name = "";
$address = "";
$id = 0;
$update = false;

if (isset($_POST['save'])) {
    $name = $_POST['name'];
    $address = $_POST['address'];

    mysqli_query($db, "INSERT INTO info (name, address) VALUES ('$name', '$address')");
    $_SESSION['message'] = "Address saved";
    header('location: index.php');
}
if (isset($_POST['update'])) {
    $id = $_POST['id'];
    $name = $_POST['name'];
    $address = $_POST['address'];

    mysqli_query($db, "UPDATE info SET name='$name', address='$address' WHERE id=$id");
    $_SESSION['message'] = "Address updated!";
    header('location: index.php');
}
if (isset($_GET['del'])) {
    $id = $_GET['del'];
    mysqli_query($db, "DELETE FROM info WHERE id=$id");
    $_SESSION['message'] = "Address deleted!";
    header('location: index.php');
}

Answer 1

And your code is fully prone to SQL injection

阅读有关 PHP 准备好的语句的信息。 https://www.w3schools.com/php/php_mysql_prepared_statements.asp

假设文件 1 名称为 codefile.php，包含连接的文件 2 为 connection.php 因此，写入 codefile.php include("connection.php") 将 codefile.php 中的 $db 更改为 $conn，就像 connection.php 中一样，您已经在 $conn 变量

中创建了连接

检查下方 link: w3schools.com/php/php_includes.asp

codefile.php

 <?php
    include("connection.php");
    $results = mysqli_query($conn, "SELECT * FROM info");
    ?>

    <!DOCTYPE html>
    <html>
    <head>
        <title>CRUD: CReate, Update, Delete PHP MySQL</title>
    </head>
    <body>
    ..................
    ..................
    ..................

connection.php

<?php
session_start();
$db_host = "localhost"; 
$db_location = " "; 
$db_name = "crud"; 
$conn= mysqli_connect ($db_host,$db_name, $db_location,$db_name)or die ("could not connect to mysql");
..................
..................
..................

使用 HTML 和 MYSQL PHP 的 CRUD 操作

CRUD OPERATION USING HTML and MYSQL PHP

html

php

mysql

parameters

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