!3579 feat(#I641HK): add AutoSelectFirstWhenValueIsNull on RadioList component

* chore: bump version 7.0.10
* test: 增加单元测试
* doc: 更新示例
* feat: 增加 AutoSelectFirstWhenValueIsNull 参数

src/BootstrapBlazor.Shared/Samples/Radios.razor.cs

@@ -70,7 +70,7 @@ public sealed partial class Radios
         };
         Items = new SelectedItem[]
         {
-            new SelectedItem("1", Localizer["Add1"]) { Active = true },
+            new SelectedItem("1", Localizer["Add1"]),
             new SelectedItem("2", Localizer["Add2"])
         };
         Model = Foo.Generate(LocalizerFoo);

src/BootstrapBlazor/BootstrapBlazor.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk.Razor">
 
   <PropertyGroup>
-    <Version>7.0.10-beta03</Version>
+    <Version>7.0.10</Version>
   </PropertyGroup>
 
   <ItemGroup Condition="'$(TargetFramework)' == 'net5.0'">

src/BootstrapBlazor/Components/Radio/RadioList.razor.cs

@@ -42,6 +42,12 @@ public partial class RadioList<TValue>
     [Parameter]
     public RenderFragment<SelectedItem>? ItemTemplate { get; set; }
 
+    /// <summary>
+    /// 获得/设置 未设置选中项时是否自动选择第一项 默认 true
+    /// </summary>
+    [Parameter]
+    public bool AutoSelectFirstWhenValueIsNull { get; set; } = true;
+
     private string? GroupName => Id;
 
     private string? RadioClassString => CssBuilder.Default("radio-list")
@@ -64,7 +70,7 @@ public partial class RadioList<TValue>
 
         NullItemText ??= "";
 
-        if (!Items.Any(i => i.Value == CurrentValueAsString))
+        if (AutoSelectFirstWhenValueIsNull && !Items.Any(i => i.Value == CurrentValueAsString))
         {
             CurrentValueAsString = Items.FirstOrDefault()?.Value ?? "";
         }
@@ -77,6 +83,31 @@ public partial class RadioList<TValue>
     /// <returns></returns>
     protected override string? FormatValueAsString(TValue value) => value is SelectedItem v ? v.Value : base.FormatValueAsString(value);
 
+    /// <summary>
+    /// <inheritdoc/>
+    /// </summary>
+    /// <param name="value"></param>
+    /// <param name="result"></param>
+    /// <param name="validationErrorMessage"></param>
+    /// <returns></returns>
+    protected override bool TryParseValueFromString(string value, [MaybeNullWhen(false)] out TValue result, out string? validationErrorMessage)
+    {
+        var ret = false;
+        var t = NullableUnderlyingType ?? typeof(TValue);
+        result = default;
+        if (t == typeof(SelectedItem))
+        {
+            var item = Items.FirstOrDefault(i => i.Value == value);
+            if (item != null)
+            {
+                result = (TValue)(object)item;
+                ret = true;
+            }
+        }
+        validationErrorMessage = null;
+        return ret || base.TryParseValueFromString(value, out result, out validationErrorMessage);
+    }
+
     /// <summary>
     /// 
     /// </summary>

test/UnitTest/Components/RadioTest.cs

@@ -170,6 +170,23 @@ public class RadioTest : BootstrapBlazorTestBase
         cut.Contains("item-template-2");
     }
 
+    [Fact]
+    public void AutoSelectFirstWhenValueIsNull_Ok()
+    {
+        var cut = Context.RenderComponent<RadioList<SelectedItem>>(pb =>
+        {
+            pb.Add(a => a.AutoSelectFirstWhenValueIsNull, false);
+            pb.Add(a => a.Items, new List<SelectedItem>
+            {
+                new("1", "Test1"),
+                new("2", "Test2")
+            });
+            pb.Add(a => a.Value, new SelectedItem());
+        });
+        cut.Contains("class=\"form-check-label\"");
+        cut.DoesNotContain("is-checked");
+    }
+
     [Fact]
     public void ValidateForm_Ok()
     {