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。

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)。

我可以推荐使用混淆器。

只需编写一个好的应用程序和一个简单的保护系统。不管你选择什么保护，它都会被逆转……所以不要浪费太多时间/金钱。