public static void AttributesMethod()
{
//attribute is a class that inherit of Attribute class.
//One function of attibutes is tag methods, classes, types and so on, in order to query down tagged members in reflection.
//you can create properties in an attribute (must have get; set; statements) and assign values when you tag members
//you can create a constructor in an attribute and assign parameters when you tag members
//you can make restrictions in attributes (to use just in clases, delegates, methods ans so on)
//1. Get the assembly
Assembly assembly = Assembly.GetExecutingAssembly();
// select all the types which have at least one tag or attribute with myCustomAttribute
var myCustomAttributeQuery = from t in assembly.GetTypes()
where t.GetCustomAttributes <myCustomAttribute>().Count() > 0
select t;
foreach (var type in myCustomAttributeQuery)
{
Console.WriteLine(type.Name);
//Get all properties tagged with myCustomAttribute
var properties = from property in type.GetProperties()
where property.GetCustomAttributes <myCustomAttribute>().Count() > 0
select property;
foreach (PropertyInfo property in properties)
{
Console.WriteLine(property.Name);
}
var methods = from method in type.GetMethods()
where method.GetCustomAttributes <myCustomAttribute>().Count() > 0
select method;
foreach (MethodInfo method in methods)
{
Console.WriteLine(method.Name);
}
}
//Getting the property values of a custom Attribute
//1. get the type of the tagged class and of the attibute
Type TransportationType = typeof(transportation);
Type customAttrType = typeof(CustomAttr);
//2.execute the GetCustomAttribute method from the abstract class Attribute
CustomAttr ca = (CustomAttr)Attribute.GetCustomAttribute(TransportationType, customAttrType);
Console.WriteLine("{0}, {1}", ca.antiguity, ca.medium);
//You can create a constructor in an attribute an inicialize in when you tag the member
}
public OrderComparer()
{
Type objType = typeof(T);
foreach (PropertyInfo oneProp in objType.GetProperties())
{
CustomAttr customOrder = (CustomAttr)oneProp.GetCustomAttribute(typeof(CustomAttr), true);
if (customOrder == null)
{
continue;
}
sortOrder.Add(customOrder.Order, oneProp);
}
}
