Asp.net Core 反射加载dll

1. 定义一个类库，定义接口

namespace Plugin
{public interface IPlugin{void EllisTest();}
}

2. 定义另外一个类库，引用上面的类库，实现接口

using Plugin;namespace UserCustom
{public class Custom : IPlugin{public  void EllisTest(){Console.WriteLine("哈哈，今天这个天气挺好的");}}
}

3. 定义API，使用assemble加载dll

[HttpGet(Name = "test")]
public IActionResult DirectLoad()
{Assembly assembly = Assembly.LoadFrom("C:\\Users\\84977\\Desktop\\UserCustom.dll");var pluginType = assembly.GetTypes().FirstOrDefault(t => typeof(IPlugin).IsAssignableFrom(t) && !t.IsInterface && !t.IsAbstract);if (pluginType != null){IPlugin plugin = (IPlugin)Activator.CreateInstance(pluginType);plugin.EllisTest();}return Ok();
}[HttpGet(Name = "GetWeatherForecast")]
public IEnumerable<WeatherForecast> Get()
{string pluginPath = "C:\\Users\\84977\\Desktop\\UserCustom.dll";var pluginLoader = new PluginLoader();pluginLoader.LoadAndExecutePlugin(pluginPath);return Enumerable.Range(1, 5).Select(index => new WeatherForecast{Date = DateTime.Now.AddDays(index),TemperatureC = Random.Shared.Next(-20, 55),Summary = Summaries[Random.Shared.Next(Summaries.Length)]}).ToArray();
} 

4. 使用AssemblyLoadContext 加载dll

public class CustomAssemblyLoadContext : AssemblyLoadContext{public CustomAssemblyLoadContext() : base(isCollectible: true){}protected override Assembly Load(AssemblyName assemblyName){return null; // 返回 null 以使用默认的加载机制}}public class PluginLoader{public void LoadAndExecutePlugin(string pluginPath){var context = new CustomAssemblyLoadContext();// 加载插件程序集var assembly = context.LoadFromAssemblyPath(pluginPath);// 查找实现了 IPlugin 接口的类型var pluginType = assembly.GetTypes().FirstOrDefault(t => typeof(IPlugin).IsAssignableFrom(t) && !t.IsInterface && !t.IsAbstract);if (pluginType != null){// 创建插件实例并调用方法var plugin = (IPlugin)Activator.CreateInstance(pluginType);plugin.EllisTest();}assembly = null;GC.Collect();GC.WaitForPendingFinalizers();context.Unload();// 在此处，当 using 块结束时，AssemblyLoadContext 会被卸载，从而实现 DLL 的热卸载。}}