如何从Unity连接到数据库 [英] How to connect to database from Unity
问题描述
我正在尝试通过Unity连接到MS SQL数据库.但是，当我尝试打开连接时，出现IOException:连接丢失.
I am trying to connect to a MS SQL database through Unity. However, when I try to open a connection, I get an IOException: Connection lost.
我已经从Unity \ Editor \ Data \ Mono \ lib \ mono \ 2.0导入了System.Data.dll.我正在使用以下代码:
I have imported System.Data.dll from Unity\Editor\Data\Mono\lib\mono\2.0. I am using the following code:
using UnityEngine;
using System.Collections;
using System.Data.Sql;
using System.Data.SqlClient;
public class SQL_Controller : MonoBehaviour {
string conString = "Server=myaddress.com,port;" +
"Database=databasename;" +
"User ID=username;" +
"Password=password;";
public string GetStringFromSQL()
{
LoadConfig();
string result = "";
SqlConnection connection = new SqlConnection(conString);
connection.Open();
Debug.Log(connection.State);
SqlCommand Command = connection.CreateCommand();
Command.CommandText = "select * from Artykuly2";
SqlDataReader ThisReader = Command.ExecuteReader();
while (ThisReader.Read())
{
result = ThisReader.GetString(0);
}
ThisReader.Close();
connection.Close();
return result;
}
}
这是我得到的错误:
IOException: Connection lost
Mono.Data.Tds.Protocol.TdsComm.GetPhysicalPacketHeader ()
Mono.Data.Tds.Protocol.TdsComm.GetPhysicalPacket ()
Mono.Data.Tds.Protocol.TdsComm.GetByte ()
Mono.Data.Tds.Protocol.Tds.ProcessSubPacket ()
Mono.Data.Tds.Protocol.Tds.NextResult ()
Mono.Data.Tds.Protocol.Tds.SkipToEnd ()
Rethrow as TdsInternalException: Server closed the connection.
Mono.Data.Tds.Protocol.Tds.SkipToEnd ()
Mono.Data.Tds.Protocol.Tds70.Connect (Mono.Data.Tds.Protocol.TdsConnectionParameters connectionParameters)
Mono.Data.Tds.Protocol.Tds80.Connect (Mono.Data.Tds.Protocol.TdsConnectionParameters connectionParameters)
请忽略此方法的任何安全风险，我需要进行此测试，安全性将在稍后发布. 谢谢您的时间.
Please disregard any security risks with this approach, I NEED to do this for testing, security will come later. Thank you for your time.
推荐答案
请忽略此方法带来的任何安全风险
Please disregard any security risks with this approach
不要这样.安全性是在安全保护之前还是之后都没有关系.您将结束重新编写整个代码的过程，因为密码已在您的应用程序中进行了硬编码，可以轻松地对其进行反编译和检索.现在以正确的方式进行连接，这样您就不必重新编写整个应用程序.
Do not do it like this. It doesn't matter if security will come before or after. You will end of re-writing the whole code because the password is hard-coded in your application which can be decompiled and retrieved easily. Do the connection the correct way now so that you won't have to re-write the whole application.
使用php，perl或任何您喜欢的语言在服务器上运行数据库命令，但这应该在服务器上完成.
Run your database command on your server with php, perl or whatever language you are comfortable with but this should be done on the server.
在Unity中，使用 WWW 或示例 /a/25200894/3785314>有.即使这样，您仍然需要实现自己的安全性，但这比您现在拥有的安全性要好得多.
From Unity, use the WWW or UnityWebRequest class to communicate with that script and then, you will be able to send and receive information from Unity to the server. There are many examples out there. Even with this, you still need to implement your own security but this is much more better than what you have now.
您还可以使用 json 接收多个数据.
You can also receive data multiple with json.
以下是此 Unity Wiki中的完整示例.它显示了如何使用服务器端的php和客户端的Unity + C#与Unity中的数据库进行交互.
Below is a complete example from this Unity wiki. It shows how to interact with a database in Unity using php on the server side and Unity + C# on the client side.
服务器端:
使用PDO添加分数:
<?php
// Configuration
$hostname = 'localhot';
$username = 'yourusername';
$password = 'yourpassword';
$database = 'yourdatabase';
$secretKey = "mySecretKey"; // Change this value to match the value stored in the client javascript below
try {
$dbh = new PDO('mysql:host='. $hostname .';dbname='. $database, $username, $password);
} catch(PDOException $e) {
echo '<h1>An error has ocurred.</h1><pre>', $e->getMessage() ,'</pre>';
}
$realHash = md5($_GET['name'] . $_GET['score'] . $secretKey);
if($realHash == $hash) {
$sth = $dbh->prepare('INSERT INTO scores VALUES (null, :name, :score)');
try {
$sth->execute($_GET);
} catch(Exception $e) {
echo '<h1>An error has ocurred.</h1><pre>', $e->getMessage() ,'</pre>';
}
}
?>
使用PDO检索得分:
<?php
// Configuration
$hostname = 'localhost';
$username = 'yourusername';
$password = 'yourpassword';
$database = 'yourdatabase';
try {
$dbh = new PDO('mysql:host='. $hostname .';dbname='. $database, $username, $password);
} catch(PDOException $e) {
echo '<h1>An error has occurred.</h1><pre>', $e->getMessage() ,'</pre>';
}
$sth = $dbh->query('SELECT * FROM scores ORDER BY score DESC LIMIT 5');
$sth->setFetchMode(PDO::FETCH_ASSOC);
$result = $sth->fetchAll();
if(count($result) > 0) {
foreach($result as $r) {
echo $r['name'], "\t", $r['score'], "\n";
}
}
?>
在服务器上启用跨域策略:
此文件应命名为"crossdomain.xml"，并放置在Web服务器的根目录中. Unity要求您要通过WWW请求访问的网站具有跨域策略.
This file should be named "crossdomain.xml" and placed in the root of your web server. Unity requires that websites you want to access via a WWW Request have a cross domain policy.
<?xml version="1.0"?>
<cross-domain-policy>
<allow-access-from domain="*"/>
</cross-domain-policy>
客户端/统一端:
来自Unity的客户端代码连接到服务器，与PDO交互，并根据调用哪个函数来添加或检索分数.对该客户端代码进行了少许修改，以使用最新的Unity版本进行编译.
The client code from Unity connects to the server, interacts with PDO and adds or retrieves score depending on which function is called. This client code is slightly modified to compile with the latest Unity version.
private string secretKey = "mySecretKey"; // Edit this value and make sure it's the same as the one stored on the server
public string addScoreURL = "http://localhost/unity_test/addscore.php?"; //be sure to add a ? to your url
public string highscoreURL = "http://localhost/unity_test/display.php";
//Text to display the result on
public Text statusText;
void Start()
{
StartCoroutine(GetScores());
}
// remember to use StartCoroutine when calling this function!
IEnumerator PostScores(string name, int score)
{
//This connects to a server side php script that will add the name and score to a MySQL DB.
// Supply it with a string representing the players name and the players score.
string hash = Md5Sum(name + score + secretKey);
string post_url = addScoreURL + "name=" + WWW.EscapeURL(name) + "&score=" + score + "&hash=" + hash;
// Post the URL to the site and create a download object to get the result.
WWW hs_post = new WWW(post_url);
yield return hs_post; // Wait until the download is done
if (hs_post.error != null)
{
print("There was an error posting the high score: " + hs_post.error);
}
}
// Get the scores from the MySQL DB to display in a GUIText.
// remember to use StartCoroutine when calling this function!
IEnumerator GetScores()
{
statusText.text = "Loading Scores";
WWW hs_get = new WWW(highscoreURL);
yield return hs_get;
if (hs_get.error != null)
{
print("There was an error getting the high score: " + hs_get.error);
}
else
{
statusText.text = hs_get.text; // this is a GUIText that will display the scores in game.
}
}
public string Md5Sum(string strToEncrypt)
{
System.Text.UTF8Encoding ue = new System.Text.UTF8Encoding();
byte[] bytes = ue.GetBytes(strToEncrypt);
// encrypt bytes
System.Security.Cryptography.MD5CryptoServiceProvider md5 = new System.Security.Cryptography.MD5CryptoServiceProvider();
byte[] hashBytes = md5.ComputeHash(bytes);
// Convert the encrypted bytes back to a string (base 16)
string hashString = "";
for (int i = 0; i < hashBytes.Length; i++)
{
hashString += System.Convert.ToString(hashBytes[i], 16).PadLeft(2, '0');
}
return hashString.PadLeft(32, '0');
}
这只是有关如何正确执行此操作的示例.如果您需要实现会话功能并关心安全性，请查看 OAuth 2.0 协议.应该有现有的库可以帮助您开始使用 OAuth 协议.
This is just an example on how to properly do this. If you need to implement session feature and care about security, look into the OAuth 2.0 protocol. There should be existing libraries that will help get started with the OAuth protocol.
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