Clearable fluent validator

Demo.Forms/Models/NestedForm.cs

@@ -13,6 +13,14 @@ public class NestedForm
         public List<ChildForm> SubArray { set; get; }
 
         public MustNotValidate NotAForm { set; get; }
+
+        public void Clear()
+        {
+            Email = String.Empty;
+            Child = new ChildForm();
+            SubArray = new List<ChildForm> { new ChildForm { }, new ChildForm { } };
+            NotAForm = new MustNotValidate();
+        }
     }
 
     public class ChildForm

Demo/Pages/Index.razor

@@ -19,7 +19,7 @@
 <h1>Form 2: Dependency Injection Validation</h1>
 
 <EditForm Model="Form2">
-    <FluentValidator></FluentValidator>
+    <FluentValidator @ref="Form2FluentValidator"></FluentValidator>
     <div class="form-group">
         <label for="email">Email</label>
         <InputText id="email" class="form-control" @bind-Value="Form2.Email"></InputText>
@@ -54,6 +54,9 @@
         </button>
     </div>
 </EditForm>
+<button class="btn btn-primary" @onclick="ClearForm2">
+    Clear Form
+</button>
 
 <h1>Submitting / Editing This Form Will Crash The App</h1>
 
@@ -85,4 +88,13 @@
     };
 
     CrashForm CrashForm = new CrashForm();
+
+    FluentValidator Form2FluentValidator;
+
+    void ClearForm2()
+    {
+        Form2.Clear();
+        Form2FluentValidator.ClearMessages();
+    }
+
 }

FluentValidation.Blazor/Accelist.FluentValidation.Blazor.csproj

@@ -32,6 +32,7 @@ Version 5.0.0 BREAKING CHANGES:
 - Package sub-dependency Microsoft.AspNetCore.Components.Web is changed to Microsoft.AspNetCore.Components.Forms to allow using the library in Xamarin Blazor project!
 - Package is now compatible with both .NET 5.0 and .NET Core 3.1
 		</PackageReleaseNotes>
+		<PackageId>ClearableFluentValidation.Blazor</PackageId>
 	</PropertyGroup>
 
 	<ItemGroup>

FluentValidation.Blazor/FluentValidator.cs

@@ -43,6 +43,11 @@ public class FluentValidator : ComponentBase, IDisposable
         [Parameter]
         public Dictionary<Type, IValidator> ChildValidators { set; get; } = new Dictionary<Type, IValidator>();
 
+        /// <summary>
+        /// <see cref="ValidationMessageStore"/> that gathers all validation messages linked to <see cref="FluentValidator"/>.
+        /// </summary>
+        protected ValidationMessageStore MessageStore { get; set; }
+
         /// <summary>
         /// Attach to parent EditForm context enabling validation.
         /// </summary>
@@ -57,6 +62,8 @@ protected override void OnInitialized()
 
             this.ServiceScope = ServiceProvider.CreateScope();
 
+            MessageStore = new ValidationMessageStore(CurrentEditContext);
+
             if (this.Validator == null)
             {
                 this.SetFormValidator();
@@ -65,6 +72,16 @@ protected override void OnInitialized()
             this.AddValidation();
         }
 
+        /// <summary>
+        /// Clear all validation messages.
+        /// </summary>
+        public void ClearMessages()
+        {
+            MessageStore.Clear();
+            CurrentEditContext.MarkAsUnmodified();
+            CurrentEditContext.NotifyValidationStateChanged();
+        }
+
         /// <summary>
         /// Try setting the EditContext form model typed validator implementation from the DI.
         /// </summary>
@@ -122,28 +139,27 @@ private IValidationContext CreateValidationContext(object model, IValidatorSelec
         /// </summary>
         private void AddValidation()
         {
-            var messages = new ValidationMessageStore(CurrentEditContext);
 
             // Perform object-level validation on request
             CurrentEditContext.OnValidationRequested +=
-                (sender, eventArgs) => ValidateModel((EditContext)sender, messages);
+                (sender, eventArgs) => ValidateModel((EditContext)sender);
 
             // Perform per-field validation on each field edit
             CurrentEditContext.OnFieldChanged +=
-                (sender, eventArgs) => ValidateField(CurrentEditContext, messages, eventArgs.FieldIdentifier);
+                (sender, eventArgs) => ValidateField(CurrentEditContext, eventArgs.FieldIdentifier);
         }
 
         /// <summary>
         /// Validate the whole form and trigger client UI update.
         /// </summary>
         /// <param name="editContext"></param>
         /// <param name="messages"></param>
-        private async void ValidateModel(EditContext editContext, ValidationMessageStore messages)
+        private async void ValidateModel(EditContext editContext)
         {
             // <EditForm> should now be able to run async validations:
             // https://github.com/dotnet/aspnetcore/issues/11914
             var validationResults = await TryValidateModel(editContext);
-            messages.Clear();
+            MessageStore.Clear();
 
             var graph = new ModelGraphCache(editContext.Model);
             foreach (var error in validationResults.Errors)
@@ -153,7 +169,7 @@ private async void ValidateModel(EditContext editContext, ValidationMessageStore
                 if (propertyValue != null)
                 {
                     var fieldID = new FieldIdentifier(propertyValue, propertyName);
-                    messages.Add(fieldID, error.ErrorMessage);
+                    MessageStore.Add(fieldID, error.ErrorMessage);
                 }
             }
 
@@ -238,7 +254,7 @@ private IValidator TryGetFieldValidator(EditContext editContext, in FieldIdentif
         /// <param name="editContext"></param>
         /// <param name="messages"></param>
         /// <param name="fieldIdentifier"></param>
-        private async void ValidateField(EditContext editContext, ValidationMessageStore messages, FieldIdentifier fieldIdentifier)
+        private async void ValidateField(EditContext editContext, FieldIdentifier fieldIdentifier)
         {
             var fieldValidator = TryGetFieldValidator(editContext, fieldIdentifier);
             if (fieldValidator == null)
@@ -248,11 +264,11 @@ private async void ValidateField(EditContext editContext, ValidationMessageStore
             }
 
             var validationResults = await TryValidateField(fieldValidator, editContext, fieldIdentifier);
-            messages.Clear(fieldIdentifier);
+            MessageStore.Clear(fieldIdentifier);
 
             foreach (var error in validationResults.Errors)
             {
-                messages.Add(fieldIdentifier, error.ErrorMessage);
+                MessageStore.Add(fieldIdentifier, error.ErrorMessage);
             }
 
             editContext.NotifyValidationStateChanged();
@@ -277,6 +293,7 @@ protected virtual void Dispose(bool disposing)
                 ServiceScope = null;
                 Validator = null;
                 ChildValidators = null;
+                MessageStore = null;
 
                 disposedValue = true;
             }