Question : Saving and retrieving object to file using XML in VS2005

I'm trying to create a generic method for saving an object out to a file and retrieving it again.  I'm guessing that XML is the way to go, but all of the examples I find require a higher level of .NET than I have access to.

What I want is something like this:

public class Employee {
   private string name = "";
   private string ssn = "";
   public Employee() {
   }
   public string name {
      get { return this.name; }
      set { this.name = value; }
   }
   public string SSN {
      get { return this.ssn; }
      set { this.ssn = value; }
   }
}

I want to be able to use it like this:

   Employee emp = new Employee();
   SaveObject(emp, @"c:\temp\myemp");

   ...and then later
   Employee emp = RetrieveObject(@"c:\temp\myemp");

Can this be done with VS2005?  What would the methods contain?

Answer : Saving and retrieving object to file using XML in VS2005

It is more complicated than it appears so I have attached some code that will do it (see below) as a PHP class. This is only a very simple basket but it can be easily extended.

It is used like so

$b = new myBasket("basketName");    // You can run several baskets, just use unique names

$b->addItem( $productCode );  // Adds 1 item

$b->addItem( $productCode2, 10 );   // Adds a quantity of 10 for productCode2


To display the basket

$items = $b->fetchAllItems();
$qty    = $b->fetchAllQtys();

foreach( $items  as $index=> $aProductCode ) {

     echo "Product code $aProductCode has {$qty[$index]} items<br/>";
}
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<?php

class myBasket {

     protected $basket;                 // Variable for working with the basket
     protected $qty;                    // Number of items in a given basket entry

     private   $sessName;               // Session variable name
     private   $sessQty;                // Session variable for quantities


     // ----- Constructor -----------------------------------------------------


     // Parameters: $name - The basket must have a name to store the data against
     //
     function myBasket( $name ) {

          $this->sessName = $name . "_bskt";
          $this->sessQty  = $name . "_qty";

          $this->initialise();
     }





     // ----- Private methods -------------------------------------------------


     // Store the current array in a session variable
     //
     private function updateBasket() {
          $_SESSION[$this->sessName] = serialize($this->basket);
          $_SESSION[$this->sessQty]  = serialize($this->qty);
     }



     // Initialise the basket
     //
     private function initialise() {

          // Check if session is in progress and if so retrieve the existing basket
          //
          if ( isset($_SESSION [$this->sessName]) && isset($_SESSION [$this->sessQty]) ) {
               $this->basket = unserialize( $_SESSION[$this->sessName] );
               $this->qty    = unserialize( $_SESSION[$this->sessQty] );
          }
          else {
               $this->basket = array();
               $this->qty    = array();
               $this->updateBasket();
          }

     }



     // ----- Public methods --------------------------------------------------


     // Empty the basket out
     //
     function clear() {

          unset( $_SESSION [$this->sessName] );
          unset( $_SESSION [$this->sessQty ] );
          $this->initialise();
     }



     // Add an object to the end of the list
     //
     // Parameters: $item - an object to be stored
     //             $num - a quantity to be stored, defaults to 1
     //
     function addItem( $item, $num=1 ) {
          // Ensure the indexes stay in step by retrieving the highest
          // existing index and incrementing it
          //
          $ctr = count( $this->basket );

          if ( $ctr > 0 ) {
               $lastKey = end(array_keys($this->qty));
               $ctr = $lastKey + 1;
          }

          $this->basket [$ctr] = $item;
          $this->qty    [$ctr] = $num;

          $this->updateBasket();
     }



     // Remove an item from the list - identify by the basket number.
     // NOTE THAT REMOVING AN ITEM DOES NOT RESET THE BASKET NUMBERS in the arrays.
     //
     // Parameters: $basketNumber - the index of the array entry to remove from the array
     //
     function rmvItem( $basketNumber ) {

          if ( count($this->basket) > 0 ) {

               // 001 Check that an item exists before attempting its removal
               //
               if ( isset( $this->basket [$basketNumber]  ) ) {
                    unset( $this->basket [$basketNumber] );
                    unset( $this->qty [$basketNumber] );
                    $this->updateBasket();
               }
          }
     }



     // Fetch an item
     //
     // Parameters: $basketNumber - the index of the array entry to retrieve from the array
     //
     function fetchItem( $basketNumber ) {
          if ( count($this->basket) > 0 ) {
               return $this->basket [$basketNumber] ;
          }
     }



     // Fetch a quantity for an item
     //
     // Parameters: $basketNumber - the index of the qty to retrieve from the array
     //
     function fetchItemQuantity( $basketNumber ) {
          if ( count($this->qty) > 0 ) {
               return $this->qty [$basketNumber] ;
          }
     }


     // Change a given item in the list
     //
     // Parameters: $basketNumber - the index of the object to update
     //             $anItem - an object
     //
     function chgItem( $basketNumber, $anItem ) {
          if ( $basketNumber >= 0 && count($this->basket) > 0 ) {
               // 001 Check that an item exists before attempting its removal
               //
               if ( isset( $this->basket [$basketNumber]  ) ) {
                    $this->basket[$basketNumber] = $anItem;
                    $this->updateBasket();
               }
          }
     }



     // Change a given items quantity in the list
     //
     // Parameters: $basketNumber - the index of the object to update
     //             $qty - The new quantity
     //
     function chgQty( $basketNumber, $qty ) {
          if ( $basketNumber >= 0 && count($this->qty) > 0 ) {

               // 001 Check that an item exists before attempting its removal
               //
               if ( isset( $this->basket [$basketNumber]  ) ) {
                    $this->qty[$basketNumber] = $qty;
                    $this->updateBasket();
               }
          }
     }



     // Get a list of all the items in the basket
     //
     function fetchAllItems() {
          return $this->basket;
     }



     // Get a list of all the item quantities stored in the basket
     //
     function fetchAllQtys() {
          return $this->qty;
     }



     // Returns the count of the number of items in the basket
     //
     function countBasket(){
          return array_sum( $this->qty );
     }



} // End of class myBasket
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