AfterGetAttribute Class

Marks an action to be performed in a property getter after the value is retrieved from the backing store.

Syntax

Visual Basic
C#

'Declaration
 
<AttributeUsageAttribute(ValidOn=AttributeTargets.Method, 
   AllowMultiple=True, 
   Inherited=True)>
Public Class AfterGetAttribute 
   Inherits PropertyInterceptorAttribute
   Implements System.Runtime.InteropServices._Attribute

'Usage
 
Dim instance As AfterGetAttribute

[AttributeUsage(ValidOn=AttributeTargets.Method, 
   AllowMultiple=true, 
   Inherited=true)]
public class AfterGetAttribute : PropertyInterceptorAttribute, System.Runtime.InteropServices._Attribute

Remarks

Use AfterGet to specify one or more actions to be performed when a property getter is invoked. These actions occur after the backing value is retrieved. Actions may be defined as instance or static methods on a base or derived type. The execution order may be specified by using the Order named parameter. See the Developer's Guide for more information on action chaining and ordering. AfterGet interceptor actions are automatically discovered the first time a property getter is called.

There are a number of acceptable signatures for methods marked with this attribute. In general, you can accept (or accept and return) an object of the expected property type, or accept one of the many derivations of PropertyInterceptorArgs. See the examples provided with the constructors for more information. If a signature is invalid, you will receive a PropertyInterceptorException when DevForce either builds or tries to execute the method, depending on when detected.

Example

public partial class Customer {

  // Sample signatures for a AfterGet method for any Customer property
  // (both simple and navigation properties).
  // Additional signatures are possible.

  // Signature 1 - accept a property value and return a property value.
  // Any value returned is passed to the next interceptor.
  [AfterGet]
  public object AfterGetAnyCustomerProperty1(object value) {
    Console.WriteLine("AfterGet on a customer property 1");
    return value;
  }

  // Signature 2 - accept a property value, but no return value.
  [AfterGet]
  public void AfterGetAnyCustomerProperty2(object value) {
    Console.WriteLine("AfterGet on a customer property 2");
  }

  // Signature 3 - accept base IPropertyInterceptorArgs.
  // Allows you to cancel further actions and modify the Value.
  // No property information available.
  [AfterGet]
  public void AfterGetAnyCustomerProperty3(IPropertyInterceptorArgs args) {
    Console.WriteLine("AfterGet on a customer property 3");
  }

  // Signature 4 - accept EntityProperty interceptor arguments.
  // The arguments passed allow you to determine the property retrieved
  // and to to cancel further actions and modify the Value.
  [AfterGet]
  public void AfterGetAnyCustomerProperty4(IEntityPropertyGetInterceptorArgs args) {
    Console.WriteLine("Got customer property " + args.EntityProperty.Name);
  }

  // Signature 5 - accept strongly-typed IPropertyInterceptorArgs.
  // Same features as IPropertyInterceptorArgs but Instance is now strongly-typed.
  [AfterGet]
  public void AfterGetAnyCustomerProperty5(IPropertyInterceptorArgs<Customer, object> args) {
    Customer c = args.Instance;
    Console.WriteLine("AfterGet on a customer property 5");
  }
}

Inheritance Hierarchy

System.Object
   System.Attribute
      IdeaBlade.Core.PropertyInterceptorAttribute
         IdeaBlade.Core.AfterGetAttribute

Requirements

Target Platforms: Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

Reference

AfterGetAttribute Members
IdeaBlade.Core Namespace
PropertyInterceptorArgs Class
PropertyInterceptorAction Class