refactor: 更新值

Author: ArgoZhang

src/BootstrapBlazor.Server/Components/Samples/SelectCities.razor

@@ -26,7 +26,7 @@
         <div class="col-12 col-sm-6">
             <BootstrapInputGroup>
                 <BootstrapInputGroupLabel DisplayText="IsMultiple"></BootstrapInputGroupLabel>
-                <Switch @bind-Value="@_isMultiple"></Switch>
+                <Switch Value="@_isMultiple" OnValueChanged="OnValueChagned"></Switch>
             </BootstrapInputGroup>
         </div>
         <div class="col-12 col-sm-6">

src/BootstrapBlazor.Server/Components/Samples/SelectCities.razor.cs

@@ -19,4 +19,12 @@ public partial class SelectCities
     private bool _isDisabled = false;
 
     private bool _autoClose = true;
+
+    private Task OnValueChagned(bool v)
+    {
+        _value = "";
+        _isMultiple = v;
+        StateHasChanged();
+        return Task.CompletedTask;
+    }
 }