feat: 实现 ItemsTemplate 模板功能

Author: ArgoZhang

src/BootstrapBlazor/Components/Dropdown/Dropdown.razor

@@ -54,7 +54,27 @@
         }
         else
         {
-            @ItemsTemplate
-        }
+			<CascadingValue Value="_items" IsFixed="true">
+				@ItemsTemplate
+			</CascadingValue>
+			<RenderTemplate>
+				@foreach(var item in _items)
+				{
+					if (item is DropdownDivider)
+					{
+						<Divider></Divider>
+					}
+					else if (item is DropdownItem t)
+					{
+						var disabled = GetItemTriggerClick(t);
+						<DynamicElement @key="t" class="@GetItemClassString(disabled)"
+										TriggerClick="!disabled" OnClick="() => OnClickItem(t)">
+							<i class="@GetItemIconString(t)"></i>
+							<span>@t.Text</span>
+						</DynamicElement>
+					}
+				}
+			</RenderTemplate>
+		}
     </div>
 </div>

src/BootstrapBlazor/Components/Dropdown/Dropdown.razor.cs

@@ -205,6 +205,8 @@ public partial class Dropdown<TValue>
     /// </summary>
     private bool _isAsyncLoading;
 
+    private readonly List<IDropdownItem> _items = [];
+
     /// <summary>
     /// OnParametersSet 方法
     /// </summary>
@@ -290,4 +292,22 @@ private async Task HandlerClick()
             await OnClick.InvokeAsync();
         }
     }
+
+    private static string? GetItemIconString(DropdownItem item) => CssBuilder.Default("dropdown-item-icon")
+        .AddClass(item.Icon, !string.IsNullOrEmpty(item.Icon))
+        .Build();
+
+    private static string? GetItemClassString(bool disabled) => CssBuilder.Default("dropdown-item")
+        .AddClass("disabled", disabled)
+        .Build();
+
+    private static bool GetItemTriggerClick(DropdownItem item) => item.OnDisabledCallback?.Invoke(item) ?? item.Disabled;
+
+    private static async Task OnClickItem(DropdownItem item)
+    {
+        if (item.OnClick != null)
+        {
+            await item.OnClick();
+        }
+    }
 }

src/BootstrapBlazor/Components/Dropdown/Dropdown.razor.scss

@@ -9,3 +9,9 @@
         margin-inline-start: 0.25rem;
     }
 }
+
+.dropdown-menu {
+    .divider {
+        margin: 0.25rem 0;
+    }
+}