用的net core版本是2.1，也许在后续的版本中已经修复了这个问题
今天在尝试用net core写demo的时候，发现了这个问题。因为都是使用DI，所以就没有我的网站项目里直接引用一些实现类库，而是放到了同一个目录下，在网站启动的时候用代码去加载进来。然而在实际的运行过程成中发现，指定的dll会自动加载，但是其依赖的nuget包里的dll不会被加载进来，在Google了很久，也发现了很多人提出过这个问题，在GitHub上也有人提过https://github.com/dotnet/corefx/issues/21982，但是都没有直接的解决方案，其中有一个差不多的解决方案https://www.codeproject.com/Articles/1194332/Resolving-Assemblies-in-NET-Core，我的解决方案也是依据这个改进而来的。
代码的核心思路是去找需要手动加载的DLL的依赖项，尝试去找到该依赖项所在的位置，然后再加载进来。详细代码如下:
using Microsoft.Extensions.DependencyInjection;using Microsoft.Extensions.DependencyModel;using Microsoft.Extensions.DependencyModel.Resolution;using System;using System.Collections.Concurrent;using System.Collections.Generic;using System.Linq;using System.Reflection;using System.Runtime.Loader;using ZRB.Blog.Configurations;namespace ZRB.Blog.Injection{ ???public static class AssemblyLoader ???{ ???????private static readonly ICompilationAssemblyResolver AssemblyResolver; ???????private static readonly ConcurrentDictionary<string, CompilationLibrary> DependencyDLL; ???????static AssemblyLoader() ???????{ ???????????AssemblyLoadContext.Default.Resolving += Default_Resolving; ???????????AssemblyResolver = new CompositeCompilationAssemblyResolver( ???????????????new ICompilationAssemblyResolver[]{ ???????????????????new AppBaseCompilationAssemblyResolver(AppDomain.CurrentDomain.BaseDirectory), ???????????????????new ReferenceAssemblyPathResolver(), ???????????????????new PackageCompilationAssemblyResolver() ???????????????}); ???????????DependencyDLL = new ConcurrentDictionary<string, CompilationLibrary>(); ???????} ???????private static Assembly Default_Resolving(AssemblyLoadContext assemblyLoadContext, AssemblyName assemblyName) ???????{ ???????????if(DependencyDLL.ContainsKey(assemblyName.Name)) ???????????{ ???????????????var compilationLibrary = DependencyDLL[assemblyName.Name]; ???????????????var assemblies = new List<string>(); ???????????????if (AssemblyResolver.TryResolveAssemblyPaths(compilationLibrary, assemblies) && assemblies.Count > 0) ???????????????{ ???????????????????var assembly = assemblyLoadContext.LoadFromAssemblyPath(assemblies[0]); ???????????????????FindDependency(assembly); ???????????????????return assembly; ???????????????} ???????????} ???????????return null; ???????} ???????public static Assembly GetAssembly(string assemblyName) ???????{ ???????????string assemblyFileName = AppDomain.CurrentDomain.BaseDirectory + assemblyName + ".dll"; ???????????Assembly assembly = AppDomain.CurrentDomain.GetAssemblies().FirstOrDefault(a => a.FullName?.Split(‘,‘)[0] == assemblyName) ?? AssemblyLoadContext.Default.LoadFromAssemblyPath(assemblyFileName); ???????????FindDependency(assembly); ???????????return assembly; ???????} ???????private static void FindDependency(Assembly assembly) ???????{ ???????????DependencyContext dependencyContext = DependencyContext.Load(assembly); ???????????if(dependencyContext!= null) ???????????{ ???????????????foreach (var compilationLibrary in dependencyContext.CompileLibraries) ???????????????{ ???????????????????if (!DependencyDLL.ContainsKey(compilationLibrary.Name) ???????????????????&& !AppDomain.CurrentDomain.GetAssemblies().Any(a => a.FullName.Split(‘,‘)[0] == compilationLibrary.Name)) ???????????????????{ ???????????????????????RuntimeLibrary library = dependencyContext.RuntimeLibraries.FirstOrDefault(runtime => runtime.Name == compilationLibrary.Name); ???????????????????????var cb = new CompilationLibrary( ???????????????????????????library.Type, ???????????????????????????library.Name, ???????????????????????????library.Version, ???????????????????????????library.Hash, ???????????????????????????library.RuntimeAssemblyGroups.SelectMany(g => g.AssetPaths), ???????????????????????????library.Dependencies, ???????????????????????????library.Serviceable); ???????????????????????DependencyDLL[library.Name] = cb; ???????????????????} ???????????????} ???????????} ???????} ???}}net core手动加载dll，无法自动加载其依赖项
原文地址：https://www.cnblogs.com/zhurongbo/p/10423231.html