refactor: 增加数据结构

Author: ArgoZhang

src/components/BootstrapBlazor.Region/Data/CityItem.cs

@@ -0,0 +1,12 @@
+// Copyright (c) BootstrapBlazor & Argo Zhang (argo@live.ca). All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+// Website: https://www.blazor.zone or https://argozhang.github.io/
+
+namespace BootstrapBlazor.Components;
+
+readonly record struct CityItem
+{
+    public string Name { get; init; }
+
+    public string PinYin { get; init; }
+}

…trapBlazor.Region/Services/CountyItem.cs …ootstrapBlazor.Region/Data/CountyItem.cssrc/components/BootstrapBlazor.Region/Services/CountyItem.cs renamed to src/components/BootstrapBlazor.Region/Data/CountyItem.cs src/components/BootstrapBlazor.Region/Services/CountyItem.cs renamed to src/components/BootstrapBlazor.Region/Data/CountyItem.cs

@@ -0,0 +1,14 @@
+// Copyright (c) BootstrapBlazor & Argo Zhang (argo@live.ca). All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+// Website: https://www.blazor.zone or https://argozhang.github.io/
+
+namespace BootstrapBlazor.Components;
+
+readonly record struct ProvinceItem
+{
+    public string Name { get; init; }
+
+    public string PinYin { get; init; }
+
+    public HashSet<CityItem> Cities { get; init; }
+}