CODEWITHSUNDEEP
c#custom-attributes
bcuzz
bcuzz

Reputation: 147

Custom Attribute that uses Type as a property

I have the following custom attribute that I would like to have a type name as a property. However, I do not want to have to use the string representation of the type when using the attribute. Example:

public class HelpMeAttribute : Attribute
{
    public string TypeName { get; set; }
}

And to use it, I thought this

[HelpMe(TypeName = typeof(MyClass2).FullName]
public class MyClass1
{
}

public class MyClass2
{
}

I get the error: "An attribute must be a constant expression, typeof expression or array creation expression of an attribute parameter type."

I would prefer not to do:

[HelpMe(TypeName = "MyClass2"]

because that seems bad to have the type in a string. Better to let the compiler check that the type I am putting in the attribute exists.

Can someone point me down the path of enlightenment to fix this?

Upvotes: 1

Views: 478

Answers (1)

p.s.w.g
p.s.w.g

Reputation: 149058

Attribute initializers can only use compile-time constants or System.Type properties.

So why not just use Type?

public class HelpMeAttribute : Attribute
{
    public Type Type { get; set; }
    ...

    public HelpMeAttribute()
    {
    }
}

...
[HelpMe(Type = typeof(MyClass2))]
public class MyClass1
{
}

Upvotes: 1

Related Questions