Question

我需要将一些具有依赖项注入的服务注入到动作过滤器中。我对[ServiceFilter]和[TypeFilter]方法很熟悉，但这有点丑陋，混乱且不清楚。

有没有一种方法可以正常设置过滤器？而不包装[ServiceFilter]或[TypeFilter]使用的过滤器？

例如我想要的：

[SomeFilterWithDI]
[AnotherFilterWithDI("some value")]
public IActionResult Index()
{
    return View("Index");
}

代替：

[ServiceFilter(typeof(SomeFilterWithDI))]
[TypeFilter(typeof(AnotherFilterWithDI), Arguments = new string[] { "some value" })]
public IActionResult Index()
{
    return View("Index");
}

看起来很不一样，这种方法对我来说似乎不正确。

Answer 1

对于[SomeFilterWithDI]，您可以参考@Kirk larkin的评论。

对于[AnotherFilterWithDI("some value")]，您可以尝试从Arguments传递TypeFilterAttribute。

ParameterTypeFilter定义接受参数。

public class ParameterTypeFilter: TypeFilterAttribute
{

    public ParameterTypeFilter(string para1, string para2):base(typeof(ParameterActionFilter))
    {
        Arguments = new object[] { para1, para2 };
    }
}

ParameterActionFilter接受传递的参数。

    public class ParameterActionFilter : IActionFilter
{
    private readonly ILogger _logger;
    private readonly string _para1;
    private readonly string _para2;

    public ParameterActionFilter(ILoggerFactory loggerFactory, string para1, string para2)
    {
        _logger = loggerFactory.CreateLogger<ParameterTypeFilter>();
        _para1 = para1;
        _para2 = para2;
    }

    public void OnActionExecuting(ActionExecutingContext context)
    {
        _logger.LogInformation($"Parameter One is {_para1}");
        // perform some business logic work

    }

    public void OnActionExecuted(ActionExecutedContext context)
    {
        // perform some business logic work
        _logger.LogInformation($"Parameter Two is {_para2}");
    }
}

作为Arguments的描述，ILoggerFactory loggerFactory由dependency injection container解析。 para1和para2由ParameterTypeFilter解析。

    //
// Summary:
//     Gets or sets the non-service arguments to pass to the Microsoft.AspNetCore.Mvc.TypeFilterAttribute.ImplementationType
//     constructor.
//
// Remarks:
//     Service arguments are found in the dependency injection container i.e. this filter
//     supports constructor injection in addition to passing the given Microsoft.AspNetCore.Mvc.TypeFilterAttribute.Arguments.
public object[] Arguments { get; set; }

使用情况

[ParameterTypeFilter("T1","T2")]
public ActionResult Parameter()
{
    return Ok("Test");
}

没有[ServiceFilter]或[TypeFilter]的过滤器中的Asp.net Core依赖项注入

1 个答案: