CODEWITHSUNDEEP
c#asp.net-web-api2custom-action-filter
Bilel Chaouadi
Bilel Chaouadi

Reputation: 933

Override a specific Action filter

In my WebApi 2 application, I've an action filter attribute in my base controller, this attribute has a boolean property with a default value which could be set in the constructor:

[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
public class MyActionFilterAttribute : ActionFilterAttribute
{
  public bool MyProperty {get; set;}

  public MyActionFilterAttribute(bool myProperty = true)
  {
    MyProperty = myProperty;
  }

  public override void OnActionExecuting(HttpActionContext actionContext)
  {
    if(MyProperty)
    {
        //DO Something
    }
  }
}

I've also a CustomValidatorFilter configured in webApi config:

config.Filters.Add(new CustomValidatorFilterAttribute());

In some actions of my controller, I want to override the behaviour of MyActionFilterAttribute by setting the value of MyProperty to false, I've added the OverrideActionFilters to my action:

[OverrideActionFilters]
[MyActionFilterAttribute(myProperty: false)]
public IHttpActionResult MyCation()
{
  //Some staff here
}

But now my custom validation not working any more because of use of OverrideActionFilters, Is there any way to redefine the OverrideActionFilters, or just to list the filter to override. Thank you for your help.

Upvotes: 0

Views: 2314

Answers (2)

yarg
yarg

Reputation: 709

You can use FindEffectivePolicy<TMetadata>() method - this will get you the value of the relevant attribute (ie. will look for a declaration in the action and if not found will get you the one declared on the controller) -

@see FilterContext.FindEffectivePolicy<TMetadata>() method

public class MyActionFilterAttribute : ActionFilterAttribute
{
  public bool MyProperty {get; set;}

  public MyActionFilterAttribute(bool myProperty = true)
  {
    MyProperty = myProperty;
  }

  public override void OnActionExecuting(ActionExecutingContext context)
  {
    var effective = = context.FindEffectivePolicy<MyActionFilterAttribute>();
    if(effective.MyProperty)
    {
        //DO Something
    }
  }
}

Upvotes: 0

Bilel Chaouadi
Bilel Chaouadi

Reputation: 933

I've created a specific attribute DoMyPropertyAttribute and then I removed the property from the MyActionFilterAttribute. In MyActionFilterAttribute I check if the action has `DoMyPropertyAttribute, if so I do the specific work:

public class DoMyPropertyAttribute : Attribute
{
}

[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
public class MyActionFilterAttribute : ActionFilterAttribute
{
  public override void OnActionExecuting(HttpActionContext actionContext)
  {
    if(actionContext.ActionDescriptor.GetCustomAttributes<DoMyPropertyAttribute>().Any())
    {
        //DO Something
    }
  }
}

In general, if we want override an action filter, we have just to skip it and then create a specific action filter that match the desired behaviour. To skip an action filter we can do:

[AttributeUsage(AttributeTargets.Class | AttributeTargets.Method)]
public class MyActionFilterAttribute : ActionFilterAttribute
{
  public override void OnActionExecuting(HttpActionContext actionContext)
  {
    if(actionContext.ActionDescriptor.GetCustomAttributes<SkipMyActionFilterAttribute>().Any())
     {
       return;
     }

    //Do something
  }
}

Upvotes: 1

Related Questions