Deep Copy of Object in C#

public class Utility
{
    public static object CloneObject(object objSource)
    {
        //step : 1 Get the type of source object and create a new instance of that type
        Type typeSource = objSource.GetType();
        object objTarget = Activator.CreateInstance(typeSource);
        //Step2 : Get all the properties of source object type
        PropertyInfo[] propertyInfo = typeSource.GetProperties(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);
        //Step : 3 Assign all source property to taget object 's properties
        foreach (PropertyInfo property in propertyInfo)
        {
            //Check whether property can be written to
            if (property.CanWrite)
            {
                //Step : 4 check whether property type is value type, enum or string type
                if (property.PropertyType.IsValueType || property.PropertyType.IsEnum || property.PropertyType.Equals(typeof(System.String)))
                {
                    property.SetValue(objTarget, property.GetValue(objSource, null), null);
                }
                //else property type is object/complex types, so need to recursively call this method until the end of the tree is reached
                else
                {
                    object objPropertyValue = property.GetValue(objSource, null);
                    if (objPropertyValue == null)
                    {
                        property.SetValue(objTarget, null, null);
                    }
                    else
                    {
                        property.SetValue(objTarget, CloneObject(objPropertyValue), null);
                    }
                }
            }
        }
        return objTarget;
    }
}

This can be also be achieved by an Object extension method that is described below.

Using Object Extension Method

public static class ObjectExtension
{
    public static object CloneObject(this object objSource)
    {
        //Get the type of source object and create a new instance of that type
        Type typeSource = objSource.GetType();
        object objTarget = Activator.CreateInstance(typeSource);
        //Get all the properties of source object type
        PropertyInfo[] propertyInfo = typeSource.GetProperties(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance);
        //Assign all source property to taget object 's properties
        foreach (PropertyInfo property in propertyInfo)
        {
            //Check whether property can be written to
            if (property.CanWrite)
            {
                //check whether property type is value type, enum or string type
                if (property.PropertyType.IsValueType || property.PropertyType.IsEnum || property.PropertyType.Equals(typeof(System.String)))
                {
                    property.SetValue(objTarget, property.GetValue(objSource, null), null);
                }
                //else property type is object/complex types, so need to recursively call this method until the end of the tree is reached
                else
                {
                    object objPropertyValue = property.GetValue(objSource, null);
                    if (objPropertyValue == null)
                    {
                        property.SetValue(objTarget, null, null);
                    }
                    else
                    {
                        property.SetValue(objTarget, objPropertyValue.CloneObject(), null);
                    }
                }
            }
        }
        return objTarget;
    }
}

Sample code and output

class Program
{
    static void Main(string[] args)
    {
        Employee emp = new Employee();
        emp.EmployeeId = 1000;
        emp.EmployeeName = "Jignesh";
        emp.Department = new Department { DepartmentId = 1, DepartmentName = "Examination" };
        Employee empClone = emp.Clone() as Employee;
        Employee empClone1 = Utility.CloneObject(emp) as Employee;
        //now Change Original Object Value
        emp.EmployeeName = "Tejas";
        emp.Department.DepartmentName = "Admin";
        //Print origianl as well as clone object properties value.
        Console.WriteLine("Original Employee Name : " + emp.EmployeeName);
        Console.WriteLine("Original Department Name : " + emp.Department.DepartmentName);
        Console.WriteLine("");
        Console.WriteLine("Clone Object Employee Name (Clone Method) : " + empClone.EmployeeName);
        Console.WriteLine("Clone Object Department Name (Clone Method) : " + empClone.Department.DepartmentName);
        Console.WriteLine("");
        Console.WriteLine("Clone Object Employee Name (Static Method) : " + empClone1.EmployeeName);
        Console.WriteLine("Clone Object Department Name (Static Method) : " + empClone1.Department.DepartmentName);
        Console.WriteLine("");
        Console.WriteLine("Clone Object Employee Name (Extension Method) : " + empClone2.EmployeeName);
        Console.WriteLine("Clone Object Department Name (Extension Method) : " + empClone2.Department.DepartmentName);
        Console.ReadKey();
    }
}

Conclusion

Using Serialization and Reflection we can create a deep copy of an object. The only disadvantage of a deep copy using serialization is that we must mark our object as "serializable".