Create delete-item.md

13/umbraco-commerce/how-to-guides/delete-item.md

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+---
+description: Learn how to remove items added to the shopping cart.
+---
+
+# Delete item from cart
+
+{% hint style="info" %}
+This guide builds on the guide on [update-cart.md). It is recommended to follow that guide before starting this one.
+{% endhint %}
+
+This will teach you how to delete an item from the cart.
+
+Your view for the `cart.cshtml` page will be similar the example below.
+
+```csharp
+@inherits UmbracoViewPage
+@{
+	var store = Model.Value<StoreReadOnly>("store", fallback: Fallback.ToAncestors);
+	var currentOrder = CommerceApi.Instance.GetCurrentOrder(store!.Id);
+	if (currentOrder == null) return;
+
+    @using (Html.BeginUmbracoForm("UpdateCart", "CartSurface"))
+  {
+    @foreach (var item in currentOrder.OrderLines.Select((ol, i) => new
+    {
+        OrderLine = ol,
+        Index = i
+    }))
+    {
+        <p>
+            @Html.Hidden($"orderLines[{item.Index}].Id", item.OrderLine.Id)
+            @item.OrderLine.Name @Html.Hidden($"orderLines[{item.Index}].Quantity", (int)item.OrderLine.Quantity, new { @type = "number" })
+            @Html.Hidden($"orderLines[{item.Index}].ProductReference", item.OrderLine.ProductReference)
+            <a href="@Url.SurfaceAction("RemoveFromCart", "CartSurface", new { OrderLineId = item.OrderLine.Id })">Remove Item</a>
+        </p>
+
+    }
+
+    <button type="submit">Update Cart</button>
+
+    var success = TempData["SuccessMessage"]?.ToString();
+
+    if (!string.IsNullOrWhiteSpace(success))
+    {
+        <div class="success">@success</div>
+    }
+  }
+}
+```
+
+The code below allows the Umbraco `SurfaceAction` to call `RemoveFromCart` when the link is clicked. It will also pass the `OrderLineId`.
+
+```csharp
+<a href="@Url.SurfaceAction("RemoveFromCart", "BasketSurface", new { OrderLineId = item.OrderLine.Id })">Remove</a>
+```
+
+## Adding the Controller
+
+For the button to work, you need to add some functionality via a Controller.
+
+Create a new Controller called `CartSurfaceController.cs`
+
+{% hint style="warning" %}
+
+The namespaces used in this Controller are important and need to be included.
+
+```
+using Microsoft.AspNetCore.Mvc;
+using Umbraco.Cms.Core.Cache;
+using Umbraco.Cms.Core.Logging;
+using Umbraco.Cms.Core.Models.PublishedContent;
+using Umbraco.Cms.Core.Routing;
+using Umbraco.Cms.Core.Services;
+using Umbraco.Cms.Core.Web;
+using Umbraco.Cms.Infrastructure.Persistence;
+using Umbraco.Cms.Web.Website.Controllers;
+using Umbraco.Commerce.Common.Validation;
+using Umbraco.Commerce.Core.Api;
+using Umbraco.Commerce.Core.Models;
+using Umbraco.Commerce.Extensions;
+using Umbraco.Extensions;
+```
+
+{% endhint %}
+
+```csharp
+public class CartSurfaceController : SurfaceController
+{
+    public CartSurfaceController(IUmbracoContextAccessor umbracoContextAccessor,
+                                 IUmbracoDatabaseFactory databaseFactory,
+                                 ServiceContext services,
+                                 AppCaches appCaches,
+                                 IProfilingLogger profilingLogger,
+                                 IPublishedUrlProvider publishedUrlProvider,
+                                 IUmbracoCommerceApi commerceApi)
+                                 : base(umbracoContextAccessor, databaseFactory, services, appCaches, profilingLogger, publishedUrlProvider)
+    {
+        _commerceApi = commerceApi;
+    }
+}
+```
+
+The example below is the equivalent code for having this as a Primary Constructor:
+
+```csharp
+public class CartSurfaceController(IUmbracoContextAccessor umbracoContextAccessor,
+                                   IUmbracoDatabaseFactory databaseFactory,
+                                   ServiceContext services,
+                                   AppCaches appCaches,
+                                   IProfilingLogger profilingLogger,
+                                   IPublishedUrlProvider publishedUrlProvider,
+                                   IUmbracoCommerceApi commerceApi)
+                                   : SurfaceController(umbracoContextAccessor, databaseFactory, services, appCaches, profilingLogger, publishedUrlProvider)
+{
+}
+```
+
+
+
+The `CartDto` is a class used to pass data to the Controller. In this instance, it passes over the `OrderLineId`.
+
+```csharp
+    public class CartDto
+    {
+        public Guid OrderLineId { get; set; }
+    }
+```
+
+You need to add the `Action` to delete the item from the cart. This will be called when the button is clicked.
+
+```csharp
+[HttpGet]
+public IActionResult RemoveFromCart(CartDto cart)
+{
+    try
+    {
+        _commerceApi.Uow.Execute(uow =>
+        {
+            var store = CurrentPage?.Value<StoreReadOnly>("store", fallback: Fallback.ToAncestors);
+
+            if (store == null) return;
+
+            var order = _commerceApi.GetOrCreateCurrentOrder(store.Id)
+            .AsWritable(uow)
+            .RemoveOrderLine(cart.OrderLineId);
+
+            _commerceApi.SaveOrder(order);
+
+            uow.Complete();
+        });
+    }
+    catch (ValidationException)
+    {
+        ModelState.AddModelError(string.Empty, "Failed to remove product from cart");
+
+        return CurrentUmbracoPage();
+    }
+
+    TempData["SuccessMessage"] = "Item removed";
+
+    return RedirectToCurrentUmbracoPage();
+}
+```
+
+- A `try-catch` block captures any validation errors that may occur when updating items in the cart.
+- The `store` variable is used to access the store to retrieve the store ID.
+- `order` is used to retrieve the current order. In the Commerce API, everything is read-only for performance so you need to make it writable to add the product.
+- `SaveOrder` is called to save the order.
+- If there are any validation errors, they are added to a `ModelState` error, and the user is redirected back to the current page.
+- `TempData` stores a message to be displayed to the user if the product has been successfully updated.
+
+{% hint style="warning" %}
+Umbraco Commerce uses the Unit of Work pattern to complete saving the item (`uow.Complete`). When retrieving or saving data ideally you would want the entire transaction to be committed. However, if there is an error nothing is changed on the database.
+{% endhint %}
+
+If you have followed the [Add item to cart](add-item.md) article, run the application, add an item to your cart, and navigate to your `cart.cshtml` page. Clicking the `Remove Item` button will delete the item in your cart and display a message.