Backend Development
PHP Tutorial
PHP implements the question voting function in the knowledge question and answer website.
PHP implements the question voting function in the knowledge question and answer website.
PHP implements the question voting function in the Q&A website
With the popularity of smartphones and the Internet, the Q&A website has become an important platform for people to obtain information and share knowledge. A common feature in these Q&A sites is question voting. Users can rate the importance and quality of questions by voting, thereby helping other users better screen and find valuable questions.
This article will introduce how to use PHP to implement a simple question voting function. We'll use a MySQL database to store question and poll data, and HTML and CSS to build the front-end pages.
First, we need to create a database to store question and voting data. Suppose our database is called "qavote" and contains two tables "questions" and "votes". Here is the definition of the table:
CREATE TABLE questions ( id INT(11) AUTO_INCREMENT PRIMARY KEY, title VARCHAR(255) NOT NULL, content TEXT NOT NULL ); CREATE TABLE votes ( id INT(11) AUTO_INCREMENT PRIMARY KEY, question_id INT(11) NOT NULL, vote_count INT(11) NOT NULL DEFAULT 0, FOREIGN KEY (question_id) REFERENCES questions(id) );
Next, we need to create a PHP page to handle the question voting. We can name this page "vote.php". Here is a code example from the vote.php page:
<?php
// 连接数据库
$conn = new mysqli("localhost", "username", "password", "qavote");
// 检查数据库连接是否成功
if ($conn->connect_error) {
die("数据库连接失败: " . $conn->connect_error);
}
// 检查是否传入了 question_id 和 action 参数
if (isset($_GET["question_id"]) && isset($_GET["action"])) {
$question_id = $_GET["question_id"];
$action = $_GET["action"];
// 根据 action 参数执行相应的操作
if ($action == "upvote") {
// 更新问题的投票数
$sql = "UPDATE votes SET vote_count = vote_count + 1 WHERE question_id = " . $question_id;
$conn->query($sql);
} elseif ($action == "downvote") {
// 更新问题的投票数
$sql = "UPDATE votes SET vote_count = vote_count - 1 WHERE question_id = " . $question_id;
$conn->query($sql);
}
}
// 关闭数据库连接
$conn->close();
?>In vote.php, we first connect to the database and then check whether the question_id and action parameters were passed in. Based on the value of the action parameter, we update the number of votes for the corresponding question. Finally, we close the database connection. Note that to simplify the example, we do not do input validation and security. In practical applications, these are necessary.
Finally, we need to create an HTML page that displays the questions and voting results. The following is a simple example:
<!DOCTYPE html>
<html>
<head>
<title>问题投票</title>
<style>
.question {
margin-bottom: 20px;
}
</style>
</head>
<body>
<?php
// 连接数据库
$conn = new mysqli("localhost", "username", "password", "qavote");
// 检查数据库连接是否成功
if ($conn->connect_error) {
die("数据库连接失败: " . $conn->connect_error);
}
// 查询问题和投票数
$sql = "SELECT questions.id, questions.title, questions.content, votes.vote_count FROM questions
LEFT JOIN votes ON questions.id = votes.question_id";
$result = $conn->query($sql);
// 循环输出问题和投票结果
if ($result->num_rows > 0) {
while ($row = $result->fetch_assoc()) {
echo "<div class='question'>";
echo "<h3>" . $row["title"] . "</h3>";
echo "<p>" . $row["content"] . "</p>";
echo "<p>投票数: " . $row["vote_count"] . "</p>";
echo "<a href='vote.php?question_id=" . $row["id"] . "&action=upvote'>赞同</a>";
echo "<a href='vote.php?question_id=" . $row["id"] . "&action=downvote'>反对</a>";
echo "</div>";
}
} else {
echo "暂无问题";
}
// 关闭数据库连接
$conn->close();
?>
</body>
</html>In the above HTML page, we first connect to the database, then query the number of questions and votes, and output the questions and voting results based on the query results. For each question, we provide "thumbs up" and "thumbs down" links that users can click to vote. In practical applications, we can control voting permissions based on the user's login status.
Summary:
In this article, we learned how to use PHP and MySQL to implement the question voting function in a knowledge Q&A website. We created a database to store the questions and poll data and wrote the corresponding PHP pages and HTML pages. Although this is just a simple example, it can provide a good starting point for you to build more complete and complex Q&A websites. Hope this article can be helpful to you!
The above is the detailed content of PHP implements the question voting function in the knowledge question and answer website.. For more information, please follow other related articles on the PHP Chinese website!
Hot AI Tools
Undresser.AI Undress
AI-powered app for creating realistic nude photos
AI Clothes Remover
Online AI tool for removing clothes from photos.
Undress AI Tool
Undress images for free
Clothoff.io
AI clothes remover
Video Face Swap
Swap faces in any video effortlessly with our completely free AI face swap tool!
Hot Article
Hot Tools
Notepad++7.3.1
Easy-to-use and free code editor
SublimeText3 Chinese version
Chinese version, very easy to use
Zend Studio 13.0.1
Powerful PHP integrated development environment
Dreamweaver CS6
Visual web development tools
SublimeText3 Mac version
God-level code editing software (SublimeText3)
Hot Topics
PHP 8.4 Installation and Upgrade guide for Ubuntu and Debian
Dec 24, 2024 pm 04:42 PM
PHP 8.4 brings several new features, security improvements, and performance improvements with healthy amounts of feature deprecations and removals. This guide explains how to install PHP 8.4 or upgrade to PHP 8.4 on Ubuntu, Debian, or their derivati
How To Set Up Visual Studio Code (VS Code) for PHP Development
Dec 20, 2024 am 11:31 AM
Visual Studio Code, also known as VS Code, is a free source code editor — or integrated development environment (IDE) — available for all major operating systems. With a large collection of extensions for many programming languages, VS Code can be c
Explain JSON Web Tokens (JWT) and their use case in PHP APIs.
Apr 05, 2025 am 12:04 AM
JWT is an open standard based on JSON, used to securely transmit information between parties, mainly for identity authentication and information exchange. 1. JWT consists of three parts: Header, Payload and Signature. 2. The working principle of JWT includes three steps: generating JWT, verifying JWT and parsing Payload. 3. When using JWT for authentication in PHP, JWT can be generated and verified, and user role and permission information can be included in advanced usage. 4. Common errors include signature verification failure, token expiration, and payload oversized. Debugging skills include using debugging tools and logging. 5. Performance optimization and best practices include using appropriate signature algorithms, setting validity periods reasonably,
PHP Program to Count Vowels in a String
Feb 07, 2025 pm 12:12 PM
A string is a sequence of characters, including letters, numbers, and symbols. This tutorial will learn how to calculate the number of vowels in a given string in PHP using different methods. The vowels in English are a, e, i, o, u, and they can be uppercase or lowercase. What is a vowel? Vowels are alphabetic characters that represent a specific pronunciation. There are five vowels in English, including uppercase and lowercase: a, e, i, o, u Example 1 Input: String = "Tutorialspoint" Output: 6 explain The vowels in the string "Tutorialspoint" are u, o, i, a, o, i. There are 6 yuan in total
Explain late static binding in PHP (static::).
Apr 03, 2025 am 12:04 AM
Static binding (static::) implements late static binding (LSB) in PHP, allowing calling classes to be referenced in static contexts rather than defining classes. 1) The parsing process is performed at runtime, 2) Look up the call class in the inheritance relationship, 3) It may bring performance overhead.
How do you parse and process HTML/XML in PHP?
Feb 07, 2025 am 11:57 AM
This tutorial demonstrates how to efficiently process XML documents using PHP. XML (eXtensible Markup Language) is a versatile text-based markup language designed for both human readability and machine parsing. It's commonly used for data storage an
What are PHP magic methods (__construct, __destruct, __call, __get, __set, etc.) and provide use cases?
Apr 03, 2025 am 12:03 AM
What are the magic methods of PHP? PHP's magic methods include: 1.\_\_construct, used to initialize objects; 2.\_\_destruct, used to clean up resources; 3.\_\_call, handle non-existent method calls; 4.\_\_get, implement dynamic attribute access; 5.\_\_set, implement dynamic attribute settings. These methods are automatically called in certain situations, improving code flexibility and efficiency.
PHP and Python: Comparing Two Popular Programming Languages
Apr 14, 2025 am 12:13 AM
PHP and Python each have their own advantages, and choose according to project requirements. 1.PHP is suitable for web development, especially for rapid development and maintenance of websites. 2. Python is suitable for data science, machine learning and artificial intelligence, with concise syntax and suitable for beginners.
