Question

I like to use enum as value holders whereever possible and I like it. It is easy to use i.e. just put a dot and see values. It is a good replacement of hard code some time.

But still it has some limitations. We cannot put special characters in values and some other.

Actually I am trying to make code reusable. Please guide me. Is there some technique or way that I can use some data structure like enum that is flexible but have no limitations.

Answer 1

If I cannot use an enum for a set of predefined values, I use a class of static constants. They look much the same in use, but the values can be anything from a decimal to a string to a struct or class. I’ve done this for predefined cell color schemes in GridViews, much like the built-in Color class has predefined constant values. Mathematical and scientific constants such as e and Pi (if you wanted different values than are provided by the Math class), or the acceleration of gravity (9.8m/s²), or the speed of light (299,792,458m/s), can also be specified in this way.

If you think you can’t use Enums because you need to store predefined string values, try this handy trick using the System.ComponentModel Description attribute:

public Enum MyStrings
{
   [Description("This is string one")] StringOne,
   [Description("This is a different string")] StringTwo,
   ...
}

To get the strings out, you simply examine the Description attribute, the code for which is a little messy but can be easily hidden behind an extension method:

public static string GetDescription(this Enum enumValue)
    {
        object[] attr = enumValue.GetType().GetField(enumValue.ToString())
            .GetCustomAttributes(typeof (DescriptionAttribute), false);

        return (attr.Length > 0) 
            ? ((DescriptionAttribute) attr[0]).Description 
            : String.Empty;            
    }

Usage:

var stringOne = MyStrings.StringOne.GetDescription(); //"This is string one"

In this case, you can also consider using a Resource file. The value of the string can be changed from outside the scope of the program, without a recompile.