How to update the total price of an item according to its quantity?

Question

I am developing a shopping cart website. On my cart page, the total price of an item should be updated as per the quantity of that item. https://github.com/darryldecode/laravelshoppingcart I installed this shopping cart package.

How can I update the total price of an item according to its quantity?

CartController.php

id())->getContent();
        
         return view ('cart');
     }
   

    public function show($id)
    {
        $product = Product::find($id);
       
        return view('cart')->with(compact('product'));
   }


    public function update($rowId)
    {

        \Cart::session(auth()->id())->update($rowId, [
            'quantity' => [
            'relative' => true, 
            'value'=> request('quantity')
            ]
            ]);
        return back();
        
    }


    public function destroy($itemId)
    {

        \Cart::session(auth()->id())->remove($itemId);
        
        return back();
        
    }

    public function addtocart(Product $product)
    {
    
        \Cart::session(auth()->id())->add(array(
            'id' => $product->id,
            'name' => $product->prod_name,
            'price' => $product->prod_price,
            'quantity' => 1,
            'attributes' => array(),
            'associatedModel' => $product
                 ));
                
                 return redirect()->back();
    }

}

cart.blade.php

                        @foreach(\Cart::session(auth()->id())->getContent() as $items)
                            
                                
                            
                                
                                    {{ $items ['name'] }}
                                
                            
                                
                                    LKR {{ $items ['price'] }}.00
                                
                            
                                
                                    Quantity
                                    
                                        

                                        
                                             
                                                
                                                    
                                                
                                                    
                                                    
                                                        
                                                    
                                                    
                                                        
                                                    
                                                 
                                            
                                        
                                    
                                

                                 
                                                
                                        
                                        
                                   
                                    
                                
                                
                                
                                    
                                    LKR  {{Cart::session(auth()->id())->get($items->id)->getPriceSum()}}.00
                                    
                                
                                
                                    
                                         
                                         
                                    
                               
                                
                                
                             
                         @endforeach

web.php

Route::get('/cart', 'CartController@index')->name('cart.index')->middleware('auth');;
Route::get('/cart/{cartItems}', 'CartController@add')->name('cart.add')->middleware('auth');
Route::get('/cart/destroy/{itemId}', 'CartController@destroy')->name('cart.destroy')->middleware('auth');
Route::get('/cart/update/{itemId}', 'CartController@update')->name('cart.update')->middleware('auth');
Route::get('/add-to-cart/{product}','CartController@addtocart')->name('addToCart');

user_2617344 · Answer

Not much idea about Laravel, but this solution in javascript will give you an idea how you can proceed...

function getPriceSum() {
    YOUR_ARRAY.reduce((sum, item) => { return sum + (item.price * item.quantity), 0 })
}

user_11687251 · Answer

You have to change some codes:

1- Add a new route and method to retrieve all card items

Route::get('/cart/items', 'CartController@allItems')->name('cart.all-items')->middleware('auth');

method:

public function allItems()
    {
      return \Cart::session(auth()->id())->getContent();
    }

2- next, you need to move and alter this block of code into Javascript and retrieve data from the above route by Ajax.

 @foreach(\Cart::session(auth()->id())->getContent() as $items)
                                
                                    
                                    x
                                    
                                    
                                        {{ $items ['name'] }}
                                    
                                        LKR {{ $items ['price'] }}.00
                                    
                                    
                                        Quantity
                                        
                                        
                                            
                                                
                                                    
                                                
                                                
                                                    
                                                        
                                                    
                                                    
                                                        
                                                    
                                                
                                            
                                         
                                        
                                    
                                    
                                        
                                            {{Cart::session(auth()->id())->get($items->id)->getPriceSum()}}
                                        
                                    
                                @endforeach

whenever a new product adds into your card or by an interval timer you can call the method of Javascript to get the latest products without refreshing the page.

user_8394091 · Answer

I'm starting to forget Laravel and I do not have one near me, so this code below is just theoretical.

First of all, you need a backend to be able to update quantity on-the-fly. This is just your "normal" update, but it will return JSON with new total.

public function updateQuantity($rowId)
{
    \Cart::session(auth()->id())->update($rowId, [
        'quantity' => [
        'relative' => true, 
        'value'=> request('quantity')
        ]
        ]);
    $newTotal = Cart::session(auth()->id())->get($items->id)->getPriceSum();
    return [ 'total' => $newTotal ];
}

New route for that:

Route::get('/cart/updateQuantity/{itemId}', 'CartController@updateQuantity')->name('cart.updateQuantity')->middleware('auth');

Now we need to prepare frontend to be able to update quantity and total dynamically.







{{route('cart.updateQuantity',$items->id)}}


{{Cart::session(auth()->id())->get($items->id)->getPriceSum()}}

{{Cart::session(auth()->id())->get($items->id)->getPriceSum()}}

So the magic is in updateQuantity function:

function updateQuantity(itemId) {
  // here I will use jQuery just to show the idea
  const route = $('#updateQuantityRoute' + itemId);
  const newQuantity = $('#quantity' + itemId).val();
  $.post(route, {'quantity': newQuantity}).done(function( data ) {
    // here we have response
    if (typeof data === 'string') data = JSON.parse(data);
    const updatedTotal = data.total;
    $('#total' + itemId).innerText = updatedTotal; // update in DOM
  });
}

How to update the total price of an item according to its quantity?

3 Answers