feat: 增加选择逻辑

Author: ArgoZhang

src/components/BootstrapBlazor.Region/Components/SelectCity.razor

@@ -23,7 +23,7 @@
                 <ul>
                     @foreach (var city in GetCities(item))
                     {
-                        <li class="">@city</li>
+                        <li class="@GetActiveClass(city)" @onclick="() => OnSelectCity(city)">@city</li>
                     }
                 </ul>
             </div>

src/components/BootstrapBlazor.Region/Components/SelectCity.razor.cs

@@ -16,6 +16,10 @@ public partial class SelectCity
         .AddClassFromAttributes(AdditionalAttributes)
         .Build();
 
+    private readonly HashSet<string> _values = [];
+
+    private string? GetActiveClass(string item) => _values.Contains(item) ? "active" : null;
+
     private async Task OnClearValue()
     {
         CurrentValue = "";
@@ -26,6 +30,19 @@ private async Task OnClearValue()
         }
     }
 
+    private void OnSelectCity(string item)
+    {
+        if (_values.Contains(item))
+        {
+            _values.Remove(item);
+        }
+        else
+        {
+            _values.Add(item);
+        }
+        CurrentValue = string.Join(",", _values);
+    }
+
     private static HashSet<string> GetProvinces()
     {
         return