Allow fields as component state

sample/BitzArt.Blazor.State.SampleApp/BitzArt.Blazor.State.SampleApp.Client/Components/Counter.razor

@@ -4,7 +4,7 @@
 
     <h4>@Name</h4>
 
-    <p role="status">Current count: @Count</p>
+    <p role="status">Current count: @_count</p>
 
     <button class="btn btn-primary" @onclick="IncrementCount">Click me</button>
 

sample/BitzArt.Blazor.State.SampleApp/BitzArt.Blazor.State.SampleApp.Client/Components/Counter.razor.cs

@@ -11,10 +11,10 @@ public partial class Counter : PersistentComponentBase
     public string? Description { get; set; }
 
     [ComponentState]
-    public int Count { get; private set; } = 0;
+    private int _count = 0;
 
     [ComponentState]
-    public string InfoText { get; set; } = string.Empty;
+    private string InfoText = string.Empty;
 
     protected override async Task InitializeStateAsync()
     {
@@ -25,7 +25,7 @@ protected override async Task InitializeStateAsync()
 
     private void IncrementCount(object? state)
     {
-        Count++;
+        _count++;
         StateHasChanged();
     }
 }

sample/BitzArt.Blazor.State.SampleApp/BitzArt.Blazor.State.SampleApp.Client/Pages/CounterPage.razor

@@ -4,10 +4,20 @@
 
 <PageTitle>Counter</PageTitle>
 
+<p>Current rendermode: @RendererInfo.Name</p>
+
+@if (!RendererInfo.IsInteractive)
+{
+    <p>Waiting for interactivity..</p>
+}
+
 <Counter Name="Counter 1"
-         Description="This counter is initialized while pre-rendering"
+         Description="This counter is rendered in all render modes"
          StateId="Counter1"/>
 
-<Counter Name="Counter 2"
-         Description="This counter is initialized while pre-rendering"
-         StateId="Counter2" />
+@if (RendererInfo.IsInteractive)
+{
+    <Counter Name="Counter 2"
+             Description="This counter is only rendered in interactive render modes"
+             StateId="Counter2" />
+}

src/BitzArt.Blazor.State/Attributes/ComponentStateAttribute.cs

@@ -3,7 +3,7 @@
 /// <summary>
 /// Marks a property to be persisted between rendering environments.
 /// </summary>
-[AttributeUsage(AttributeTargets.Property, AllowMultiple = false, Inherited = true)]
+[AttributeUsage(AttributeTargets.Property | AttributeTargets.Field, AllowMultiple = false, Inherited = true)]
 public class ComponentStateAttribute : Attribute
 {
 }

src/BitzArt.Blazor.State/Models/StatePropertyMap/PersistentComponentStateInfo.cs

@@ -7,8 +7,14 @@ internal class PersistentComponentStateInfo(Type componentType)
     public Type ComponentType { get; set; } = componentType;
 
     public IEnumerable<StatePropertyInfo> StateProperties { get; set; }
-        = componentType.GetProperties()
+        = componentType.GetProperties(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance)
             .Where(p => p.GetCustomAttribute<ComponentStateAttribute>() != null)
             .Select(p => new StatePropertyInfo(componentType, p))
             .ToList();
+
+    public IEnumerable<StateFieldInfo> StateFields { get; set; }
+        = componentType.GetFields(BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Instance)
+            .Where(f => f.GetCustomAttribute<ComponentStateAttribute>() != null)
+            .Select(f => new StateFieldInfo(componentType, f))
+            .ToList();
 }

src/BitzArt.Blazor.State/Models/StatePropertyMap/StateFieldInfo.cs

@@ -0,0 +1,9 @@
+using System.Reflection;
+
+namespace BitzArt.Blazor.State;
+
+internal class StateFieldInfo(Type componentType, FieldInfo fieldInfo)
+{
+    public Type ComponentType { get; set; } = componentType;
+    public FieldInfo FieldInfo { get; set; } = fieldInfo;
+}

src/BitzArt.Blazor.State/RenderStrategies/PersistentComponentRenderStrategy.cs

@@ -127,6 +127,17 @@ protected void RestoreComponentState(JsonObject state)
             var deserializedValue = value.Deserialize(propertyInfo.PropertyType, serializerOptions);
             propertyInfo.SetValue(PersistentComponent, deserializedValue);
         }
+
+        foreach (var field in stateInfo.StateFields)
+        {
+            var fieldInfo = field.FieldInfo;
+            var value = state[fieldInfo.Name];
+
+            if (value is null) continue;
+
+            var deserializedValue = value.Deserialize(fieldInfo.FieldType, serializerOptions);
+            fieldInfo.SetValue(PersistentComponent, deserializedValue);
+        }
     }
 
     private IEnumerable<string> GetComponentLocation(PersistentComponentBase component)

src/BitzArt.Blazor.State/Services/PersistentComponentStateComposer.cs

@@ -35,7 +35,17 @@ internal class PersistentComponentStateComposer(
             node.Add(property.PropertyInfo.Name, serializedValue);
         }
 
-        // Serialize descendants
+        // Serialize fields
+        foreach (var field in stateInfo.StateFields)
+        {
+            var value = field.FieldInfo.GetValue(component);
+            var serializedValue = JsonSerializer.SerializeToNode(
+                value, field.FieldInfo.FieldType, serializerOptions);
+
+            node.Add(field.FieldInfo.Name, serializedValue);
+        }
+
+        // Proceed to descendants
         foreach (var descendant in component.StateDescendants)
         {
             var descendantNode = SerializeStateNode(descendant);