是的，. net二进制文件(EXE和DLL)可以很容易地反编译成接近源代码。检查. net Reflector工具。在任何。net二进制文件上尝试一下。最好的选择是混淆文件，它们仍然可以被。net Reflector反编译，但它们会造成一团不可读的混乱。我不认为好的混淆器是免费或廉价的。一个是Visual Studio附带的Dotfuscator社区版。

如何确保应用程序不被篡改，以及如何确保注册机制不会被逆向工程。

两者都有一个非常简单的答案:不要把目标代码交给不可信的一方，比如(显然)你的客户。在您的机器上托管应用程序是否可行只取决于它的功能。

如果它不是一个web应用程序，也许你可以允许SSH登录，X转发到应用服务器(或者远程桌面连接，我猜，对于Windows)。

如果你把目标代码交给书呆子，而他们认为破解你的程序可能很有趣，那么它就会被破解。没有办法。

如果你不相信我，那就指出一个没有被破解和盗版的引人注目的应用程序。

如果你使用硬件键，它会使生产成本更高，你的用户会因此讨厌你。在地板上爬来爬去，插拔你27个不同的USB设备，这真是个婊子，因为软件制造商不信任你(我想)。

有一些包可以加密你的EXE，并在允许用户使用它时解密它

当然，绕过它的方法是破解“我能使用它吗”测试，以便它总是返回true。

一个令人讨厌的技巧可能是以一种肮脏的方式在程序的其他地方使用执行测试的操作码的字节值，这将使程序很可能崩溃，除非值刚刚好。它让你链接到一个特定的架构，尽管:-(

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…

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。

客户端上运行的任何东西都可以被反编译和破解。混淆只会让它更难。我不了解你的应用程序，但99%的情况下，我认为不值得这么做。

广义上讲，有三种人。

Those who will not buy your software and resort to cracks, or if they don't find any, not use your software at all. Don't expect to make any money from this group. They rely either on their own skills or on crackers (who tend to prioritize their time depending on your useful and how big your audience is. The more useful, the sooner a crack will be available). The group of legitimate users who will buy (pay for) your software, irrespective of what protection mechanism you use. Don't make life hard for your legitimate users by using an elaborate protection mechanism since they are going to pay for it in any case. A complex protection mechanism can easily spoil the user experience and you don't want this happening to this group. Personally, I'd vote against any hardware solution, which adds to the cost of your software. A minority who will resort to "unethical" cracking and will only pay for your software because its features are protected by a licensing mechanism. You probably don't want to make it exceedingly easy for this group to circumvent your protection. However, all that effort you spend on protecting your software will pay back, depending on how big this group of people is. This entirely depends on the type of software you're building.

根据您所说的，如果您认为有足够多的少数人可以被推动购买您的软件，那么请继续执行某种形式的保护。考虑一下你能从这些少数人身上赚到多少钱，与你花在保护上的时间相比，或者你花在第三方保护API/工具上的钱。

如果您想实现自己的解决方案，那么使用公钥加密是防止容易被黑客攻击的好方法(与对称算法相反)。例如，您可以对您的许可证(序列号或许可证文件)进行数字签名。解决这个问题的唯一方法就是反编译、修改和重新编译代码(你可以使用Simucal回答中建议的技术来增加难度)。