/// <summary>
/// 自动根据 descriptor 在注册服务时进行判断是否已经存在指定接口的服务，如果存在会跳过添加，并且可以对注册位置控制。
/// </summary>
/// <param name="collection"></param>
/// <param name="descriptor">要注册的 <see cref="ServiceDescriptor"/> 对象。</param>
public static void AddSmart(this IServiceCollection collection, SmartServiceDescriptor descriptor)
{
if (descriptor == null)
{
return;
}
switch (descriptor.Options)
{
case SmartOptions.Append:
collection.Add(descriptor);
break;
case SmartOptions.TryAdd:
collection.TryAdd(descriptor);
break;
case SmartOptions.Insert:
collection.Insert(0, descriptor);
break;
case SmartOptions.TryAppend:
collection.TryAddEnumerable(descriptor);
break;
default:
collection.Replace(descriptor);
break;
}
}
public static SmartServiceDescriptor Create(ServiceDescriptor descriptor, SmartOptions options = SmartOptions.TryAdd)
{
Guard.ArgumentNotNull(descriptor, nameof(descriptor));
SmartServiceDescriptor rd = null;
if (descriptor.ImplementationInstance != null)
{
rd = new SmartServiceDescriptor(descriptor.ServiceType, descriptor.ImplementationInstance)
{
Options = options
};
}
else if (descriptor.ImplementationFactory != null)
{
rd = new SmartServiceDescriptor(descriptor.ServiceType, descriptor.ImplementationFactory, descriptor.Lifetime)
{
Options = options
};
}
else if (descriptor.ImplementationType != null)
{
rd = new SmartServiceDescriptor(descriptor.ServiceType, descriptor.ImplementationType, descriptor.Lifetime)
{
Options = options
};
}
return(rd);
}
/// <summary>
/// 将 <see cref="ServiceDescriptor"/> 视为可替换的服务，
/// 在添加服务时自动使用 ServiceCollectionExtensions.TryAdd 方法。
/// </summary>
/// <param name="descriptor"></param>
/// <returns></returns>
public static ServiceDescriptor AsSmart(this ServiceDescriptor descriptor)
{
return(SmartServiceDescriptor.Create(descriptor));
}