Practical php Shopping Cart program

Practical php tutorial Shopping Cart program
I used to have a good experience before, but it also feels good to read it, so I would like to introduce it to a friend who needs it for reference.

<? Php
// Call an instance
Require_once 'cart. class. php ';
Session_start ();
If (! Isset ($ _ SESSION ['cart']) {
$ _ SESSION ['cart'] = new cart;
}
$ Cart = & $ _ SESSION ['cart'];

If ($ _ SERVER ['request _ method'] = "POST") & ($ _ POST ['action'] = 'add ')){
$ P = $ _ POST ['P'];
$ Items = $ cart-> add ($ p );
}
If ($ _ GET ['action'] = 'delete') & ($ _ GET ['key']! = "")){
$ Items = $ cart-> remove ($ _ GET ['key']);
}

If ($ _ SERVER ['request _ method'] = "POST") & ($ _ POST ['action'] = 'modi ')){
$ Key = $ _ POST ['key'];
$ Value = $ _ POST ['value'];
For ($ I = 0; $ I <count ($ key); $ I ){
$ Items = $ cart-> modi ($ key [$ I], $ value [$ I]);
}
}

$ Items = $ cart-> getCart ();
// Print
Echo "<table border = 1> ";
Setlocale (LC_MONETARY, 'it _ it ');
Foreach ($ items as $ item ){
Echo "<tr> <form method =" post "action =" tmp. php "> ";
Echo "<td> ID :". $ item ['id']. "<input type = hidden name = key [] value = ". $ item ['id']. "> ";
Echo "<td> product:". $ item ['name'];
Echo "<td> unit price:". $ item ['price'];
Echo "<td> <input type = text name = value [] value =". $ item ['Count']. "> ";
$ Sum = $ item ['Count'] * $ item ['price'];
Echo "<td> total:". round ($ sum, 2 );
Echo "<td> <input type = button value = 'delete' onclick =" location = '? Action = remove & key = ". $ item ['id']." '"> ";
}
Echo "<input type = hidden name = action value = modi> ";
Echo "<tr> <td colspan = 7> <input type = submit/> ";
Echo "</td> </form> </tr> </table> ";

?>
<Hr>
<Form method = "post" action = "tmp. php">
ID: <input type = "text" name = "p []"/>
Product name: <input type = "text" name = "p []"/>
Unit Price: <input type = "text" name = "p []"/>
Quantity: <input type = "text" name = "p []"/>
<Input type = hidden name = action value = add>
<Input type = "submit"/>
</Form>

 

<?
/**
* Cart
*
* Shopping cart type
*
* @ Author doodoo <pWtitle@yahoo.com.cn>
* @ Package Cart
* @ Category Cart
* @ License PHP License
* @ Access public
* @ Version $ Revision: 1.10 $
*/
Class Cart {

Var $ cart;
Var $ totalCount; // Total number of items
Var $ totalPrices; // total item amount

/**
* Cart Constructor
*
* Class constructor to ensure stable initialization of the shopping cart
*
* @ Static
* @ Access public
* @ Return void: No return Value
* @ Param void no Parameter
*/
Function Cart (){
$ This-> totalCount = 0;
$ This-> totalPrice = 0;
$ This-> cart = array ();
}
 
//}}}
// {Add ($ item)

/**
* Add items to the current shopping cart
*
* @ Access public
* @ Param array $ item product information (one-dimensional array: array (product ID, product name, product unit price, product quantity ))
* @ Return array returns the array of items in the current shopping cart.
*/
Function add ($ item ){
If (! Is_array ($ item) | is_null ($ item) return $ this-> cart;
If (! Is_numeric (end ($ item) | (! Is_numeric (prev ($ item )))){
Echo "the price and quantity must be numbers ";
Return $ this-> cart;
}
Reset ($ item); // This sentence is required, because the above judgment has moved the index of the array
$ Key = current ($ item );
If ($ key = "") return $ this-> cart;
If ($ this-> _ isExists ($ key) {// is the product already exists?
$ This-> cart [$ key] ['Count'] = end ($ item );
Return $ this-> cart;
}

$ This-> cart [$ key] ['id'] = $ key;
$ This-> cart [$ key] ['name'] = next ($ item );
$ This-> cart [$ key] ['price'] = next ($ item );
$ This-> cart [$ key] ['Count'] = next ($ item );

Return $ this-> cart;
}

//}}}
// {Add ($ item)

/**
* Retrieve some or all items from the current shopping cart
* When $ key = "", clear the current shopping cart
* When $ key! = "" & $ Count = "", select all items whose ID number is $ key from the current shopping cart.
* When $ key! = "" & $ Count! = "", Select $ count items with the ID number of $ key from the current shopping cart.
*
* @ Access public
* @ Param string $ key product ID
* @ Return mixed returns an array of true and false items or items in the current shopping cart
*/
Function remove ($ key = "", $ count = ""){
If ($ key = ""){
$ This-> cart = array ();
Return true;
}
If (! Array_key_exists ($ key, $ this-> cart) return false;
If ($ count = "") {// remove this item
Unset ($ this-> cart [$ key]);
} Else {// remove $ count items
$ This-> cart [$ key] ['Count']-= $ count;
If ($ this-> cart [$ key] ['Count'] <= 0) unset ($ this-> cart [$ key]);
}
Return $ this-> cart;
}

//}}}
// {Modi ($ key, $ value)

/**
* Change the number of items in the shopping cart with the product ID as $ key to $ value.
*
* @ Access public
* @ Param string $ key product ID
* @ Param int $ value number of items
* @ Return array returns the array of items in the current shopping cart;
*/
Function modi ($ key, $ value ){
If (! $ This-> _ isExists ($ key) return $ this-> cart (); // this item does not exist and is returned directly
If ($ value <= 0) {// value is too small, delete all
Unset ($ this-> cart [$ key]);
Return $ this-> cart;
}
$ This-> cart [$ key] ['Count'] = $ value;
Return $ this-> cart;
}

/**
* Returns an array of items in the current shopping cart.
*
* @ Access public
* @ Return array returns the array of items in the current shopping cart;
*/
Function getCart (){
Return $ this-> cart;
}

//}}}
// {_ IsExists ($ key)

/**
* Check whether there is a product with the ID of $ key in the current shopping cart.
*
* @ Access private
* @ Param string $ key product ID
* @ Return bool true or false;
*/
Function _ isExists ($ key)
{
If (isset ($ this-> cart [$ key]) &! Empty ($ this-> cart [$ key]) & array_key_exists ($ key, $ this-> cart ))
Return true;
Return false;
}

//}}}
// {IsEmpty ()

/**
* Determines whether the current shopping cart is empty, that is, there is no product
*
* @ Access public
* @ Return bool true or false;
*/
Function isEmpty (){
Return! Count ($ this-> cart );
}

//}}}
// {_ Stat ()

/**
* Obtain partial statistics
*
* @ Access private
* @ Return bool true or false;
*/
Function _ stat (){
If ($ this-> isEmpty () return false;
Foreach ($ this-> cart as $ item ){
$ This-> totalCount = @ end ($ item );
$ This-> totalPrices = @ prev ($ item );
}
Return true;
}

//}}}
// {TotalPrices ()

/**
* Get the total amount of all items in the current shopping cart
*
* @ Access public
* @ Return float: The returned amount;
*/
Function totalPrices (){
If ($ this-> _ stat ())
Return $ this-> totalPrices;
Return 0;
}

//}}}
// {IsEmpty ()

/**
* Obtain the total quantity and total number of all items in the current shopping cart.
*
* @ Access public
* @ Return int;
*/
Function totalCount (){
If ($ this-> _ stat ())
Return $ this-> totalCount;
Return 0;
}

} // End Class Cart
?>