Often, after filling out the form, we need to send our data to the MySQL database immediately. In this example, we will consider the option of sending data object-oriented method and the usual functional method.
In any case, we need to create a test HTML form to begin with:
<html>
<head>
<title>Test form</title>
<meta charset="utf-8" />
</head>
<body>
<form action="add-user.php" method="post">
<input type="text" name="username" placeholder="Add name" /></p>
<input type="number" name="age" placeholder="age" /></p>
<input type="submit" value="Add">
</form>
</body>
</html>
Axction of our form leads to the page add-user.php.
Let’s create this file and add the following code to it:
OOP PHP example:
if (isset($_POST["username"]) && isset($_POST["age"])) {
// Connecting to the database
$conn = new mysqli("localhost", "root", "password", "testdb");
// Checking connection errors
if ($conn->connect_error) {
die("Error: " . $conn->connect_error);
}
// Escaping special characters in a string to prevent SQL injections
$namefield = $conn->real_escape_string($_POST["username"]);
$agefield = $conn->real_escape_string($_POST["age"]);
// Preparing an SQL Query
$sql = "INSERT INTO Users (name, age) VALUES (?, ?)";
$stmt = $conn->prepare($sql);
$stmt->bind_param("si", $namefield, $agefield);
$stmt->execute();
// Adding data to the database and displaying errors
if ($stmt->affected_rows > 0) {
echo "User added";
} else {
echo "Error: " . $stmt->error;
}
// Closing a connection
$stmt->close();
$conn->close();
}
Function example:
if (isset($_POST["username"]) && isset($_POST["age"])) {
$conn = mysqli_connect("localhost", "root", "password", "testdb");
if (!$conn) {
die("Error: " . mysqli_connect_error());
}
$namefield = mysqli_real_escape_string($conn, $_POST["username"]);
$agefield = mysqli_real_escape_string($conn, $_POST["age"]);
$stmt = mysqli_prepare($conn, "INSERT INTO Users (name, age) VALUES (?, ?)");
mysqli_stmt_bind_param($stmt, "si", $namefield, $agefield);
if (mysqli_stmt_execute($stmt)) {
echo "User added";
} else {
echo "Error: " . mysqli_error($conn);
}
mysqli_stmt_close($stmt);
mysqli_close($conn);
}
mysqli_real_escape_string() – allows you to protect against SQL injections