c# - Asp .net Core 使用服务实例调用在 Startup.cs 中运行的另一个方法中的方法

Question

我有一个带有事件方法的类，它获取我需要存储到数据库的数据。

public class DataParser
{
SmsService smsService = new SmsService(..require context...);

 public void ReceiveSms()
 {
     //ParserLogic
     smsService.SaveMessage(...Values...);
 }
}

由于服务在上下文的帮助下保存数据，我需要传递它并在构造函数中初始化。在我创建要在 Startup 上运行的解析器对象时执行此操作后，ir 需要在那里传递上下文。

public class Startup
{
DataParser data = new DataParser(...requires db context...)
   public void ConfigureServices(IServiceCollection services)
    {
        //Opens port for runtime
        InnerComPortSettings.OpenPort();
        //Runtime sms receiver
        data.ReceiveSms();
    }
}

那么如何正确的将数据保存到数据库呢？

Answer 1

您需要重构您的代码。

1) 您不必在解析器中创建服务。将其作为依赖项传递

public class DataParser
{   
    public DataParser(SmsService smsService)
    {
        SmsService _smsService = smsService;
    }

    public void ReceiveSms( )
    {
        //ParserLogic
        smsService.SaveMessage(...Values...);
    }
}

2) 现在你需要注册你的上下文、解析器和服务

public void ConfigureServices(IServiceCollection services)
{
    services.AddDbContext<MyDbContext>(options =>... your options here); // register your context
    services.AddSingleton<SmsService, SmsService>(); // register your sms servcice which is required data context
    services.AddSingleton<DataParser, DataParser>(); // register your parser
}

5) 现在是时候重构您的短信服务了

public class SmsService
{
    private readonly IServiceScopeFactory _scopeFactory;

    public SmsService(IServiceScopeFactory scopeFactory)
    {
        _scopeFactory = scopeFactory;
    }

    public async Task SaveMessage(....)
    {
        using (var scope = _scopeFactory.CreateScope())
        {
            using (var ctx = scope.ServiceProvider.GetService<MyDbContext>())
            {
                ... make changes
                await ctx.SaveChangesAsync();
            }
        }
    }
}

4) 当一切都注册好后，你可以在Startup类的configure方法中解决你需要的东西

public void Configure(IApplicationBuilder app, DataParser data) // resolving your data perser and using it
{
    //Opens port for runtime
    InnerComPortSettings.OpenPort();
    //Runtime sms receiver
    data.ReceiveSms();
}

或者您可以在 Controller 、服务以及任何您想要的地方解析您的解析器。