Key steps in handling form input in PHP include: Validating input to prevent malicious code. Check for errors to ensure users fill out all fields correctly. Store data securely to prevent unauthorized access. By using filters and prepared statements, you can create secure PHP forms that handle user input.

PHP Forms: Professional Handling of User Input

Introduction

PHP Forms are An important tool for interacting with users and collecting information. When handling user input, it's crucial to ensure it's valid and safe. This article will guide you step-by-step through processing form input in PHP, including practical examples.

Step 1: Validate input

Use PHP built-in functions such as filter_input to filter and sanitize user input.

$name = filter_input(INPUT_POST, 'name', FILTER_SANITIZE_STRING);
$email = filter_input(INPUT_POST, 'email', FILTER_VALIDATE_EMAIL);

Step 2: Check for errors

Use filter_has_var and filter_input_array Check for any typographical errors.

if (filter_has_var(INPUT_POST, 'name') && filter_input_array(INPUT_POST, 'name', FILTER_VALIDATE_STRING)) {
    // 表单已正确提交
} else {
    // 显示错误消息
}

Step 3: Store data securely

Store user input in a database or other secure location. Use prepared statements to prevent SQL injection attacks.

$stmt = $db->prepare("INSERT INTO users (name, email) VALUES (?, ?)");
$stmt->bind_param("ss", $name, $email);
$stmt->execute();

Practical case: Contact form

Create a PHP script to handle contact form submission:

prepare("INSERT INTO messages (name, email, message) VALUES (?, ?, ?)");
    $stmt->bind_param("sss", $name, $email, $message);
    $stmt->execute();

    // 显示成功消息
    echo "消息已发送。谢谢您的联系。";
} else {
    // 显示错误消息
    echo "请填写所有必需的字段。";
}
?>