从抽象类派生的用户控件

Question

i am building a dynamic Winforms UI based on 12 Usercontrols which are selectable by a combobox and are derived from an abstract class (to provide a unified api).

Initiating all of them takes about 800ms (much too slow and useless because only one will be used after selection). But i have to init them to access a public Property 'Description' which i display in the combobox.

I would like to access the Property(field, const) static. But thats not possible with an interface or abstract class.

I could store the relation (UserControl <-> Description) in a Dictionay<type, string>. But the 'Description' belongs to the object.

Is there any way override/inherit a public static function/poperty/field/attribute which can be accessed static via an interface/abstract class/Reflection. So i access the Description of the Usercontrol via interface/abstract/Reflection class without instantiating the derived class?

Answer 1

System.Attribute is designed to do exactly this.

For example:

[System.ComponentModel.Description("This is my fantastic control!")]
public class MyControl : UserControl
{
    //...
}

Then when you want to get the value:

public string GetDescription(Type t)
{
    System.ComponentModel.DescriptionAttribute attrib = t.GetCustomAttribute<System.ComponentModel.DescriptionAttribute>();

    if (attrib != null)
        return attrib.Description;

    return string.Empty;
}

And to call it:

string myDescription = GetDescription(typeof(MyControl));