ASP.NET Core实现自动依赖注入_实用技巧_

 [AttributeUsage(AttributeTargets.Class, AllowMultiple = false)] public class AutoInjectAttribute : Attribute { public AutoInjectAttribute(Type interfaceType, InjectType injectType) { Type = interfaceType; InjectType = injectType; } public Type Type { get; set; } /// 
 /// 注入类型 /// 
 public InjectType InjectType { get; set; } } 

 /// 
 /// 注入类型 /// 
 public enum InjectType { Scope, Single, Transient } 

 /// 
 /// 自动依赖注入 /// 
 public static class AutoInject { /// 
 /// 自动注入所有的程序集有InjectAttribute标签 /// 
 ///  ///  public static IServiceCollection AddAutoDi(this IServiceCollection serviceCollection) { var path = AppDomain.CurrentDomain.BaseDirectory; var assemblies = Directory.GetFiles(path, "*.dll").Select(Assembly.LoadFrom).ToList(); foreach (var assembly in assemblies) { var types = assembly.GetTypes().Where(a => a.GetCustomAttribute() != null) .ToList(); if (types.Count <= 0) continue; foreach (var type in types) { var attr = type.GetCustomAttribute(); if (attr?.Type == null) continue; switch (attr.InjectType) { case InjectType.Scope: serviceCollection.AddScoped(attr.Type, type); break; case InjectType.Single: serviceCollection.AddSingleton(attr.Type, type); break; case InjectType.Transient: serviceCollection.AddTransient(attr.Type, type); break; default: throw new ArgumentOutOfRangeException(); } } } return serviceCollection; } } 

 public void ConfigureServices(IServiceCollection services) { services.AddAutoDi(); } 

 public interface ITest { string Say(); } [AutoInject(typeof(ITest),InjectType.Scope)] public class Test : ITest { public String Say() { return "test:"+DateTime.Now.ToString(); } }