Question

Currently, i have a declaration in a root class that iterates through the properties of a deriving class and instantiates the Default Value of the property, using the DefaultValueAttribute descriptor. What i want to do is expand this from simply being for DefaultValue to also be XmlElement, XmlAttribute and the series of Attributes included in the Serialization of the Xml namespace.

I am having a problem with expanding the current design to handle multiple attributes without loading a ton of if/then/else statements to handle the various Defined Attributes.

Current Design:

private void Initialize () {
  foreach( PropertyDescriptor property in TypeDescriptor.GetProperties( this ) ) {
    XmlElementAttribute xel = ( XmlElementAttribute ) property.Attributes[typeof( XmlElementAttribute )];
    if( xel != null ) {
      this.AddElement( xel.ElementName , "" );
    }
    DefaultValueAttribute attr = ( DefaultValueAttribute ) property.Attributes[typeof( DefaultValueAttribute )];
    if( attr != null ) {
      property.SetValue( this , attr.Value );
    }
  }
}

Suggestions Design:

private void Initialize () {
  foreach( PropertyDescriptor property in TypeDescriptor.GetProperties( this ) ) {
    foreach( Attribute attr in property.Attributes ) {
      if( attr = typeof(XmlElementAttribute)){
        //do something
      }else if(attr = typeof(DefaultValueAttribute)){
        //do something
      }
    }
  }
}

Answer 1

You could define a Dictionary<Type, Action<object>> (or replace object with the specific type of your class) and add the code you want to execute for each type:

var dict = new Dictionary<Type, Action<object>>();
dict.Add(typeof(XmlElementAttribute), obj =>
{
  //do something
});

Now you can just test whether your dictionary contains the type and execute the delegate:

foreach(Attribute attr in property.Attributes) 
{  
   var attributeType = attr.GetType();
   if(dict.ContainsKey(attributeType))
   {
     dict[attributeType](this);
   }
}