Pass a value from route to custom attribute

Question

I created a custom attribute and I need to pass a value from route to this attribute, how can I do this?

public class MyAttribute : Attribute
{
    public MyAttribute(string myvalue)
    {
        // use myvalue...
    }
}

[MyAttribute]
[Route("/action/{myvalue}")]
public IActionResult Action(string myvalue)
{
   
}

Answer 1

you can inject HttpContextAccessor to your attribute class and then read the route parameters

public class MyAttribute : Attribute
{
    private readonly HttpContextAccessor _accessor;

    public MyAttribute(HttpContextAccessor accessor)
    {
        _accessor = accessor; 
        var myValue = _accessor.HttpContext.Request.RouteValues.GetValueOrDefault["myValue"];
        // ...
    }
}