php - MySQL 连接功能不起作用？

Question

我正在尝试连接到我的数据库，但它显示 mysql_connect 函数出错。

错误是: fatal error :未捕获错误:调用 C:\xampp\htdocs\Connect.php:12 中的未定义函数 mysql_connect() 堆栈跟踪:#0 C:\xampp\htdocs\Test.php(3): require() #1 {main} 抛出在第 12 行的 C:\xampp\htdocs\Connect.php

连接文件:

<?php  

$db_host = "localhost"; 
// Place the username for the MySQL database here 
$db_username = "root";  
// Place the password for the MySQL database here 
$db_pass = "";  
// Place the name for the MySQL database here 
$db_name = "oscar"; 

// Run the connection here  
$con = mysql_connect("db_host","$db_username","$db_pass");
if (!$con)
{
  die('Could not connect: ' . mysql_error());
}
mysql_select_db("$db_name", $con);
try 
{
 $conn = new PDO("mysql:host=$db_host;dbname=$db_name", $db_username, $db_pass);
// set the PDO error mode to exception
 $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
 echo "Connected successfully"; 
}
catch(PDOException $e)
{
 echo "Connection failed: " . $e->getMessage();
}

?>

文本文件:

<?php
// Connect to the MySQL database  
require "Connect.php"; 
echo "Success";
?>

Answer 1

为什么同时使用 mysql_connect 和 PDO？并且 mysql 已被弃用，因此容易受到 sql 注入(inject)的攻击。<​​/p>

只有这段代码会连接到你的数据库

<?php
$db_host = "localhost";
// Place the username for the MySQL database here
$db_username = "root";
// Place the password for the MySQL database here
$db_pass = "";
// Place the name for the MySQL database here
$db_name = "oscar";


try {
    $conn = new PDO("mysql:host=$db_host;dbname=$db_name", $db_username, $db_pass);
// set the PDO error mode to exception
    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
    echo "Connected successfully";
} catch (PDOException $e) {
    echo "Connection failed: " . $e->getMessage();
}