Deep Comparison two objects if they are alike.

   
 

#region License and Copyright
/*
 * Dotnet Commons Reflection
 *
 * This library is free software; you can redistribute it and/or modify it 
 * under the terms of the GNU Lesser General Public License as published by 
 * the Free Software Foundation; either version 2.1 of the License, or 
 * (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful, but 
 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY 
 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License 
 * for more details. 
 *
 * You should have received a copy of the GNU Lesser General Public License 
 * along with this library; if not, write to the 
 * Free Software Foundation, Inc., 
 * 59 Temple Place, 
 * Suite 330, 
 * Boston, 
 * MA 02111-1307 
 * USA 
 * 
 */

#endregion

using System;
using System.Collections;
using System.IO;
using System.Reflection;
using System.Runtime.Serialization.Formatters.Binary;
using System.Text;

namespace Dotnet.Commons.Reflection
{
  /// -----------------------------------------------------------------------
  /// <summary>  
  /// This utility class contains a rich sets of utility methods that perform operations 
  /// on objects during runtime such as copying of property and field values
  /// between 2 objects, deep cloning of objects, etc.  
  /// </summary>
  /// -----------------------------------------------------------------------
  public abstract class ObjectUtils
  {


    /// ------------------------------------------------------------------------
    /// <summary>
    /// Deep Comparison two objects if they are alike. The objects are consider alike if 
    /// they are:
    /// <list type="ordered">
    ///    <item>of the same <see cref="System.Type"/>,</item>
    ///    <item>have the same number of methods, properties and fields</item>
    ///    <item>the public and private properties and fields values reflect each other&#039;s. </item>
    /// </list>
    /// </summary>
    /// <param name="original"></param>
    /// <param name="comparedToObject"></param>
    /// <returns></returns>
    /// ------------------------------------------------------------------------
    public static bool IsALike(object original, object comparedToObject) 
    { 
      
      if (original.GetType() != comparedToObject.GetType())
        return false;

      // ...............................................
      // Compare Number of Private and public Methods
      // ...............................................
      MethodInfo[] originalMethods = original
        .GetType()
        .GetMethods(BindingFlags.Instance | 
        BindingFlags.NonPublic | 
        BindingFlags.Public); 
      
      MethodInfo[] comparedMethods = comparedToObject
        .GetType()
        .GetMethods(BindingFlags.Instance | 
        BindingFlags.NonPublic | 
        BindingFlags.Public); 

      if (comparedMethods.Length != originalMethods.Length)       
        return false;
      
      // ...............................................
      // Compare Number of Private and public Properties
      // ................................................
      PropertyInfo[] originalProperties = original
        .GetType()
        .GetProperties(BindingFlags.Instance | 
        BindingFlags.NonPublic | 
        BindingFlags.Public); 

      PropertyInfo[] comparedProperties = comparedToObject
        .GetType()
        .GetProperties(BindingFlags.Instance | 
        BindingFlags.NonPublic | 
        BindingFlags.Public); 
      
      
      if (comparedProperties.Length != originalProperties.Length)
        return false;


      // ...........................................
      // Compare number of public and private fields
      // ...........................................
      FieldInfo[] originalFields = original
        .GetType()
        .GetFields(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public); 

      FieldInfo[] comparedToFields = comparedToObject
        .GetType()
        .GetFields(BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public); 

      
      if (comparedToFields.Length != originalFields.Length) 
        return false;

      // ........................................
      // compare field values
      // ........................................
      foreach (FieldInfo fi in originalFields)
      {    
    
        // check to see if the object to contains the field          
        FieldInfo fiComparedObj = comparedToObject.GetType().GetField(fi.Name, BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public);

        if (fiComparedObj == null)
          return false;

        // Get the value of the field from the original object        
        Object srcValue =  original.GetType().InvokeMember(fi.Name,
          BindingFlags.GetField | BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public,
          null,
          original,
          null);


          
        // Get the value of the field
        object  comparedObjFieldValue = comparedToObject
          .GetType()
          .InvokeMember(fiComparedObj.Name,
          BindingFlags.GetField | BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public,
          null,
          comparedToObject,
          null);

          
        // -------------------------------
        // now compare the field values
        // -------------------------------

        if (srcValue == null)
        {
          if (comparedObjFieldValue != null)
            return false;
          else
            return true;
        }

        if (srcValue.GetType() != comparedObjFieldValue.GetType())
          return false;

        if (!srcValue.ToString().Equals(comparedObjFieldValue.ToString()))
          return false;      
      } 

      // ........................................
      // compare each Property values
      // ........................................
      foreach (PropertyInfo pi in originalProperties)
      {    
    
        // check to see if the object to contains the field          
        PropertyInfo piComparedObj = comparedToObject
          .GetType()
          .GetProperty(pi.Name, BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public);

        if (piComparedObj == null)
          return false;

        // Get the value of the property from the original object        
        Object srcValue = original
          .GetType()
          .InvokeMember(pi.Name,
          BindingFlags.GetProperty | BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public,
          null,
          original,
          null);
          
        // Get the value of the property
        object  comparedObjValue = comparedToObject
          .GetType()
          .InvokeMember(piComparedObj.Name,
          BindingFlags.GetProperty | BindingFlags.Instance | BindingFlags.NonPublic | BindingFlags.Public,
          null,
          comparedToObject,
          null);

          
        // -------------------------------
        // now compare the property values
        // -------------------------------
        if (srcValue.GetType() != comparedObjValue.GetType())
          return false;

        if (!srcValue.ToString().Equals(comparedObjValue.ToString()))
          return false;      
      }
      return true; 
    } 
   }
}