WebApi实现批量注入

# 特性类
首先创建一个批量注入的特性类AppServiceAttribute，然后在类中实现以下代码：
```java

public class AppServiceAttribute : Attribute
{
    public ServiceLifeType ServiceLifeType { get; set; } = ServiceLifeType.Singleton;
    public Type ServiceType { get; set; }
}

public enum ServiceLifeType
{
    Transient, Scoped, Singleton
}
```
# 注册
```java
builder.Services.AddAppService("Services");
```
```java
 public static class AppService
 {
     public static void AddAppService(this IServiceCollection services, params string[] assemblyNames)
     {
         foreach (var name in assemblyNames)
         {
             Assembly assembly = Assembly.Load(name);
             foreach (var type in assembly.GetTypes())
             {
                 var serviceAttribute = type.GetCustomAttribute<AppServiceAttribute>();
                 if (serviceAttribute != null)
                 {
                     var serviceType = serviceAttribute.ServiceType;
                     switch (serviceAttribute.ServiceLifeType)
                     {
                         case ServiceLifeType.Singleton:
                             services.AddSingleton(serviceType, type);
                             break;
                         case ServiceLifeType.Scoped:
                             services.AddScoped(serviceType, type);
                             break;
                         case ServiceLifeType.Transient:
                             services.AddTransient(serviceType, type);
                             break;
                         default:
                             services.AddTransient(serviceType, type);
                             break;
                     }
                 }
             }
         }
     }
 }
```

# 服务
```java
[AppService(ServiceType = typeof(ISystemService))]
public class SystemService : ISystemService
{
    public int Add(int a, int b)
    {
        return a+b;
    }
}

或
[AppService(ServiceLifeType =ServiceLifeType.Scoped,ServiceType = typeof(ISystemService))]

```