根据微软博客中的以下问题:

https://blogs.msdn.microsoft.com/amb/2011/05/27/how-to-prevent-ildasm-from-disassembling-my-net-code/

如何防止ILDASM分解程序集?

. net有一个名为SuppressIldasmAttribute的属性，它可以防止分解代码。例如，考虑以下代码:

using System;
using System.Text;
using System.Runtime.CompilerServices;
[assembly: SuppressIldasmAttribute()]

namespace HelloWorld
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello world...");
        }
    }
}

如你所见，只有两个不同之处:

我们添加了System.Runtime.CompilerServices命名空间减速。 我们添加了[assembly: SuppressIldasmAttribute()]属性。

在Visual Studio中构建应用程序后，当我们尝试在ILDASM中打开生成的EXE文件时，现在我们得到以下消息:

如果您希望人们能够运行您的代码(如果您不希望，那么为什么要首先编写它?)，那么他们的CPU需要能够执行您的代码。为了能够执行代码，CPU需要能够理解它。

由于cpu是愚蠢的，而人类不是，这意味着人类也可以理解代码。

只有一种方法可以确保你的用户不会得到你的代码:不要把你的代码给他们。

这可以通过两种方式实现:软件即服务(SaaS)，即在服务器上运行软件，只允许用户远程访问它。例如，这就是Stack Overflow使用的模型。我很确定Stack Overflow不会混淆他们的代码，但是你不能反编译它。

The other way is the appliance model: instead of giving your users your code, you give them a computer containing the code. This is the model that gaming consoles, most mobile phones and TiVo use. Note that this only works if you "own" the entire execution path: you need to build your own CPU, your own computer, write your own operating system and your own CLI implementation. Then, and only then can you protect your code. (But note that even the tiniest mistake will render all of your protections useless. Microsoft, Apple, Sony, the music industry and the movie industry can attest to that.)

或者，您可以什么都不做，这意味着您的代码将自动受到版权法的保护。

Here's one idea: you could have a server hosted by your company that all instances of your software need to connect to. Simply having them connect and verify a registration key is not sufficient -- they'll just remove the check. In addition to the key check, you need to also have the server perform some vital task that the client can't perform itself, so it's impossible to remove. This of course would probably mean a lot of heavy processing on the part of your server, but it would make your software difficult to steal, and assuming you have a good key scheme (check ownership, etc), the keys will also be difficult to steal. This is probably more invasive than you want, since it will require your users to be connected to the internet to use your software.

好吧，你不能完全保护你的产品不被破解，但你可以最大化/增强安全级别，让它有点难以被新手和中级破解者破解。

但请记住，没有什么是不可破解的，只有服务器端的软件受到了很好的保护，无法被破解。无论如何，为了增强应用程序中的安全级别，您可以执行一些简单的步骤来防止某些黑客“不是全部”破解您的应用程序。下面这些步骤会让你抓狂甚至绝望:

Obfuscate your source code, obviously this will make your source code look like a mess and unreadable. Trigger several random checking routines inside your application like every two hours, 24 hours, one day, week, etc. or maybe after every action the user take. Save your released application's MD5 checksum on your server and implement a routine that can check the current file MD5 checksum with the real one on you server side and make it randomly triggered. If the MD5 checksum has been changed that means this copy has been pirated. Now you can just block it or release an update to block it, etc. Try to make a routine that can check if some of your codes (functions, classes, or specific routines) are actually have been modified or altered or even removed. I call it (code integrity check). Use free unknown packers to pack your application. Or, if you have the money, go for commercial solutions such as Thamida or .NET Reactor. Those applications get updated regularly and once a cracker unpack your application, you can just get a new update from those companies and once you get the new update, you just pack your program and release a new update. Release updates regularly and force your customer to download the latest update. Finally make your application very cheap. Don't make it too expensive. Believe me, you will get more happy customers and crackers will just leave your application, because it isn't worth their time to crack a very cheap application.

这些只是防止新手和中级破解者破解应用程序的简单方法。如果您有更多保护应用程序的想法，请不要羞于实现它们。这只会让破解者的生活变得艰难，他们会感到沮丧，最终他们会离开你的应用程序，因为它不值得他们花费时间。

最后，你还需要考虑花时间编写一个好的、高质量的应用程序。不要把时间浪费在编写复杂的安全层上。如果一个优秀的破解者想要破解你的应用程序，无论你做什么，他/她都会做。

现在去实现一些玩具饼干…

混淆代码!在混淆c#代码中有一个例子。

最好的答案是第一个来自小开发人员自己的经验，上面讨论的所有反反转技术对于任何严肃的反向工程师来说都是101个教科书案例。

一些商业DRM解决方案相当不错，但它们总是在数小时(或数天)内使用自定义DRM解决方案破解每一款AAA级游戏。只有一个全新的DRM解决方案的引入——有时——延迟是不可避免的，可能需要几个星期。

充分利用DRM需要花费大量的时间和金钱，而且很容易损害性能、可靠性、兼容性/可移植性和客户关系。要么坚持一些像样的商业DRM，不要试图太聪明，承担你的(更少的)损失，要么完全忘记它……

一个DRM解决方案的例子，它挖了自己的(商业)坟墓:http://en.wikipedia.org/wiki/StarForce