php核心技术
<?php
// PHP核心技术演示文件
// 1. 变量与数据类型
echo "<h2>PHP核心技术演示</h2>";
// 字符串操作
$name = "PHP开发者";
$version = "8.3";
echo "<p>欢迎 {$name}，当前PHP版本：{$version}</p>";
// 数组处理
$languages = ["PHP", "JavaScript", "Python", "Go"];
echo "<p>编程语言数组：<br>";
foreach($languages as $lang) {
echo "- {$lang}<br>";
}
echo "</p>";
// 函数定义与调用
function calculateArea($width, $height) {
return $width * $height;
}
$area = calculateArea(10, 5);
echo "<p>矩形面积计算：10 × 5 = {$area}</p>";
// 面向对象编程
class DatabaseConnection {
private $host;
private $username;
private $password;
public function __construct($host, $username, $password) {
$this->host = $host;
$this->username = $username;
$this->password = $password;
}
public function connect() {
return "连接到数据库 {$this->host} 成功";
}
public function __destruct() {
echo "<p>数据库连接已关闭</p>";
}
}
$db = new DatabaseConnection("localhost", "admin", "123456");
echo "<p>{$db->connect()}</p>";
// 错误处理
function divide($a, $b) {
if ($b == 0) {
throw new Exception("除数不能为零");
}
return $a / $b;
}
try {
$result = divide(10, 2);
echo "<p>除法运算结果：10 ÷ 2 = {$result}</p>";
// 这里会抛出异常
$result = divide(10, 0);
} catch (Exception $e) {
echo "<p style='color:red'>错误：{$e->getMessage()}</p>";
}
// 文件操作
$content = "这是PHP核心技术演示文件的内容\n创建时间：" . date('Y-m-d H:i:s');
file_put_contents('demo.txt', $content);
echo "<p>文件已创建：demo.txt</p>";
// 会话管理
session_start();
$_SESSION['user'] = $name;
$_SESSION['login_time'] = date('H:i:s');
echo "<p>会话已创建，用户：{$_SESSION['user']}</p>";
// 表单处理模拟
$data = [
'username' => 'testuser',
'email' => 'test@example.com',
'age' => 25
];
echo "<h3>表单数据处理：</h3>";
echo "<ul>";
foreach ($data as $key => $value) {
echo "<li>{$key}: {$value}</li>";
}
echo "</ul>";
// JSON处理
$jsonData = json_encode($data, JSON_UNESCAPED_UNICODE);
echo "<p>JSON编码数据：<br>{$jsonData}</p>";
$decodedData = json_decode($jsonData, true);
echo "<p>JSON解码验证：<br>用户名：{$decodedData['username']}</p>";
// 正则表达式
$email = "user@example.com";
if (filter_var($email, FILTER_VALIDATE_EMAIL)) {
echo "<p style='color:green'>邮箱格式验证通过：{$email}</p>";
}
// 日期时间处理
echo "<p>当前服务器时间：" . date('Y年m月d日 H:i:s') . "</p>";
// 数学函数
$numbers = [3, 7, 2, 9, 1];
echo "<p>数组最大值：" . max($numbers) . "</p>";
echo "<p>数组最小值：" . min($numbers) . "</p>";
echo "<p>数组总和：" . array_sum($numbers) . "</p>";
// 字符串处理函数
$text = "Hello PHP World";
echo "<p>字符串长度：" . strlen($text) . "</p>";
echo "<p>字符串转大写：" . strtoupper($text) . "</p>";
echo "<p>字符串替换：" . str_replace("PHP", "PHP核心技术", $text) . "</p>";
?>
