解决.net core有循环依赖时注入的问题

方案1：循环依赖的服务不直接注入，而是改成用到的地方从容器中获取

public class OrderInfoService

{
private IServiceProvider _serviceProvider;
public OrderInfoService(IServiceProvider serviceProvider)
{
_serviceProvider = serviceProvider;
}

public string GetOrderNo()
{
UserInfoService userInfoService = _serviceProvider.GetService<UserInfoService>();
return userInfoService.GenUserNo();
}
}

方案2：使用Lazy延时加载，注入时注入延迟加载的版本比如

public class OrderInfoService

{
private Lazy<UserInfoService> _userInfoService;

public OrderInfoService(Lazy<UserInfoService> userInfoService)
{
_userInfoService = userInfoService;
}
public string GetOrderNo()
{
return _userInfoService.Value.GenUserNo();
}
}

此方式需要注入

services.AddTransient(typeof(Lazy<>), typeof(Lazier<>));

internal class Lazier<T> : Lazy<T> where T : class
{
public Lazier(IServiceProvider provider)
: base(() => provider.GetRequiredService<T>())
{

}
}
参考链接：https://stackoverflow.com/questions/44934511/does-net-core-dependency-injection-support-lazyt