> For the complete documentation index, see [llms.txt](https://docs.umbcheckout.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.umbcheckout.net/v17/core-services/basket-service.md).

# Basket Service

A service which handles all things around the basket

The basket service is what and handles all the UmbCheckout Basket operations.

You can access the basket service by injecting `IBasketService` which can be found within the namespace `UmbCheckout.Core.Interfaces`

{% hint style="info" %}
Every method also has an overload that takes a `CancellationToken` as its last parameter. Call that one: the overloads without a token are `[Obsolete]`. See [Cancellation Tokens](/v17/core-services/cancellation-tokens.md).
{% endhint %}

Adding throws an `ArgumentException` (or `ArgumentOutOfRangeException`) when a line has no currency, when a quantity is outside 1–999,999, when the Basket would hold more than 100 products, or when several lines added together have different currencies. A single line is added to the Basket for its own currency.

If a [Saving notification handler](/v17/core-services/extending-umbcheckout.md) cancels a change, the Basket is left as it was.

#### Get

Gets the [Basket](/v17/core-services/object-reference/basket.md)

```csharp
Task<Basket> Get();
```

#### Add

Adds an item to the [Basket](/v17/core-services/object-reference/basket.md)

Parameters:

| Name | Detail                                                                            |
| ---- | --------------------------------------------------------------------------------- |
| item | [Item](/v17/core-services/object-reference/lineitem.md) to be added to the Basket |

```csharp
Task<Basket> Add(LineItem item);
```

#### Add Multiple

Adds multiple items to the [Basket](/v17/core-services/object-reference/basket.md)

Parameters:

| Name  | Detail                                                                             |
| ----- | ---------------------------------------------------------------------------------- |
| items | [Items](/v17/core-services/object-reference/lineitem.md) to be added to the Basket |

```csharp
Task<Basket> Add(IEnumerable<LineItem> items);
```

#### Reduce

Reduces the specified item by a count of 1 or removes from the [Basket](/v17/core-services/object-reference/basket.md) if only 1

Parameters:

| Name | Detail                                                                              |
| ---- | ----------------------------------------------------------------------------------- |
| key  | [Item](/v17/core-services/object-reference/lineitem.md) to be reduced in the Basket |

```csharp
Task<Basket> Reduce(Guid id);
```

#### Remove

Removes the specified item from the [Basket](/v17/core-services/object-reference/basket.md)

Parameters:

| Name | Detail                                                                                |
| ---- | ------------------------------------------------------------------------------------- |
| key  | [Item](/v17/core-services/object-reference/lineitem.md) to be removed from the Basket |

```csharp
Task<Basket> Remove(Guid id);
```

#### Remove Multiple

Removes multiple items from the [Basket](/v17/core-services/object-reference/basket.md)

Parameters:

| Name | Detail                                                                                 |
| ---- | -------------------------------------------------------------------------------------- |
| keys | [Items](/v17/core-services/object-reference/lineitem.md) to be removed from the Basket |

```csharp
Task<Basket> Remove(IEnumerable<Guid> ids);
```

#### Clear

Removes all items from the Basket and clears any set [Basket](/v17/core-services/object-reference/basket.md) cookies

```csharp
Task<Basket> Clear();
```

#### TotalItems

Returns the total quantity of every line in the Basket

```csharp
Task<long> TotalItems();
```

#### SubTotal

Returns the [Basket](/v17/core-services/object-reference/basket.md) subtotal (minus any shipping or tax)

```csharp
Task<decimal> SubTotal();
```


---

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