PHP belongs to the backend in web development. PHP is a server-side scripting language, mainly used to process server-side logic and generate dynamic web content. Compared with front-end technology, PHP is more used for back-end operations such as interacting with databases, processing user requests, and generating page content. Next, specific code examples will be used to illustrate the application of PHP in back-end development.
First, let’s look at a simple PHP code example for connecting to the database and querying data:
<?php // 数据库连接信息 $servername = "localhost"; $username = "root"; $password = ""; $dbname = "myDB"; // 创建数据库连接 $conn = new mysqli($servername, $username, $password, $dbname); // 检测连接 if ($conn->connect_error) { die("Connection failed: " . $conn->connect_error); } // 查询数据 $sql = "SELECT id, firstname, lastname FROM MyGuests"; $result = $conn->query($sql); // 输出数据 if ($result->num_rows > 0) { while($row = $result->fetch_assoc()) { echo "id: " . $row["id"]. " - Name: " . $row["firstname"]. " " . $row["lastname"]. "<br>"; } } else { echo "0 results"; } // 关闭连接 $conn->close(); ?>
In the above code example, we first establish a connection with the database and then perform the query operation , and output the results to the page. This process is performed on the server side and is part of the back-end logic processing.
In addition, PHP can also be combined with front-end technologies (such as HTML, CSS, JavaScript) to generate dynamic pages. Here is a simple example that demonstrates how to use PHP to generate an HTML page with dynamic content:
<?php $name = "Alice"; ?> <!DOCTYPE html> <html> <head> <title>Dynamic Web Page</title> </head> <body> <h1 id="Hello-php-echo-name">Hello, <?php echo $name; ?>!</h1> <p>Today is <?php echo date("Y-m-d"); ?>.</p> </body> </html>
In this example, the PHP code dynamically inserts the value of the $name variable into the HTML page such that Page content can be dynamically updated based on changes in back-end data.
To sum up, PHP belongs to the backend in Web development and is mainly used to process server-side logic and generate dynamic content. PHP plays an important role in back-end development by interacting with databases, processing user requests, and generating dynamic pages.
The above is the detailed content of Is PHP front-end or back-end in web development?. For more information, please follow other related articles on the PHP Chinese website!

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