[DatePicker] Prevent silently ignoring date formatting failures

examples/Demo/Shared/Microsoft.FluentUI.AspNetCore.Components.xml

@@ -669,6 +669,12 @@
             Gets the <see cref="P:Microsoft.FluentUI.AspNetCore.Components.FluentInputBase`1.FieldIdentifier"/> for the bound value.
             </summary>
         </member>
+        <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentInputBase`1.FieldDisplayName">
+            <summary>
+            Gets the display name of the field, using the specified display name if set; otherwise, uses the field
+            identifier's name if the field is bound.
+            </summary>
+        </member>
         <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentInputBase`1.CurrentValue">
             <summary>
             Gets or sets the current value of the input.
@@ -767,6 +773,16 @@
             <param name="e"></param>
             <returns></returns>
         </member>
+        <member name="T:Microsoft.FluentUI.AspNetCore.Components.ICultureSensitiveComponent">
+            <summary>
+            Defines an interface for components with values that are sensitive to culture settings, eg : parsing to string.
+            </summary>
+        </member>
+        <member name="P:Microsoft.FluentUI.AspNetCore.Components.ICultureSensitiveComponent.Culture">
+            <summary>
+            Gets or sets the culture of the component.
+            </summary>
+        </member>
         <member name="M:Microsoft.FluentUI.AspNetCore.Components.InputHelpers`1.GetMaxValue">
             <summary>
             Because of the limitation of the web component, the maximum value is set to 9999999999 for really large numbers.
@@ -779,6 +795,11 @@
             </summary>
             <returns>The minimum value for the underlying type</returns>
         </member>
+        <member name="P:Microsoft.FluentUI.AspNetCore.Components.IStringParsableComponent.ParsingErrorMessage">
+            <summary>
+            Gets or sets the error message to show when the field can not be parsed.
+            </summary>
+        </member>
         <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentBodyContent.ChildContent">
             <summary>
             Gets or sets the content to be rendered inside the component.
@@ -2999,6 +3020,9 @@
             By default <see cref="P:System.Globalization.CultureInfo.CurrentCulture"/> to display using the OS culture.
             </summary>
         </member>
+        <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentCalendarBase.ParsingErrorMessage">
+            <inheritdoc/>
+        </member>
         <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentCalendarBase.DisabledDateFunc">
             <summary>
             Function to know if a specific day must be disabled.
@@ -6703,6 +6727,9 @@
             ⚠️ Only available when Multiple = true.
             </summary>
         </member>
+        <member name="P:Microsoft.FluentUI.AspNetCore.Components.ListComponentBase`1.ParsingErrorMessage">
+            <inheritdoc/>
+        </member>
         <member name="M:Microsoft.FluentUI.AspNetCore.Components.ListComponentBase`1.#ctor">
             <summary />
         </member>
@@ -8127,11 +8154,6 @@
             An Id value must be set to use this property.
             </summary>
         </member>
-        <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentNumberField`1.ParsingErrorMessage">
-            <summary>
-            Gets or sets the error message to show when the field can not be parsed.
-            </summary>
-        </member>
         <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentNumberField`1.ChildContent">
             <summary>
             Gets or sets the content to be rendered inside the component.
@@ -8143,6 +8165,9 @@
             unless an explicit value for Min or Max is provided.
             </summary>
         </member>
+        <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentNumberField`1.ParsingErrorMessage">
+            <inheritdoc/>
+        </member>
         <member name="M:Microsoft.FluentUI.AspNetCore.Components.FluentNumberField`1.FormatValueAsString(`0)">
             <summary>
             Formats the value as a string. Derived classes can override this to determine the formatting used for <c>CurrentValueAsString</c>.
@@ -9036,6 +9061,9 @@
             Gets or sets the child content to be rendering inside the <see cref="T:Microsoft.FluentUI.AspNetCore.Components.FluentRadioGroup`1"/>.
             </summary>
         </member>
+        <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentRadioGroup`1.ParsingErrorMessage">
+            <inheritdoc/>
+        </member>
         <member name="M:Microsoft.FluentUI.AspNetCore.Components.FluentRadioGroup`1.OnParametersSet">
             <inheritdoc />
         </member>
@@ -9091,6 +9119,9 @@
             Fires when hovered value changes. Value will be null if no rating item is hovered.
             </summary>
         </member>
+        <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentRating.ParsingErrorMessage">
+            <inheritdoc/>
+        </member>
         <member name="P:Microsoft.FluentUI.AspNetCore.Components.FluentRating.GroupName">
             <summary />
         </member>

src/Core/Components/Base/FluentInputBase.cs

@@ -145,6 +145,12 @@ public abstract partial class FluentInputBase<TValue> : FluentComponentBase, IDi
 
     internal virtual bool FieldBound => Field is not null || ValueExpression is not null || ValueChanged.HasDelegate;
 
+    /// <summary>
+    /// Gets the display name of the field, using the specified display name if set; otherwise, uses the field
+    /// identifier's name if the field is bound.
+    /// </summary>
+    internal string FieldDisplayName => DisplayName ?? (FieldBound ? FieldIdentifier.FieldName : UnknownBoundField);
+
     protected async Task SetCurrentValueAsync(TValue? value)
     {
         var hasChanged = !EqualityComparer<TValue>.Default.Equals(value, Value);

src/Core/Components/Base/ICultureSensitiveComponent.cs

@@ -0,0 +1,18 @@
+// ------------------------------------------------------------------------
+// This file is licensed to you under the MIT License.
+// ------------------------------------------------------------------------
+
+using System.Globalization;
+
+namespace Microsoft.FluentUI.AspNetCore.Components;
+
+/// <summary>
+/// Defines an interface for components with values that are sensitive to culture settings, eg : parsing to string.
+/// </summary>
+public interface ICultureSensitiveComponent
+{
+    /// <summary>
+    /// Gets or sets the culture of the component.
+    /// </summary>
+    public CultureInfo Culture { get; set; }
+}

src/Core/Components/Base/IStringParsableComponent.cs

@@ -0,0 +1,16 @@
+// ------------------------------------------------------------------------
+// This file is licensed to you under the MIT License.
+// ------------------------------------------------------------------------
+
+namespace Microsoft.FluentUI.AspNetCore.Components;
+
+/// <summary>
+/// Defines an interface for components with values that can be parsed from a string.
+/// </summary>
+public interface IStringParsableComponent
+{
+    /// <summary>
+    /// Gets or sets the error message to show when the field can not be parsed.
+    /// </summary>
+    public string ParsingErrorMessage { get; set; }
+}

src/Core/Components/DateTime/FluentCalendar.razor.cs

@@ -293,9 +293,9 @@ private async Task PickerYearSelectAsync(DateTime? year)
     /// <summary />
     protected override bool TryParseValueFromString(string? value, out DateTime? result, [NotNullWhen(false)] out string? validationErrorMessage)
     {
-        BindConverter.TryConvertTo(value, Culture, out result);
-        validationErrorMessage = null;
-        return true;
+        bool success = BindConverter.TryConvertTo(value, Culture, out result);
+        validationErrorMessage = success ? null : string.Format(ParsingErrorMessage, FieldDisplayName);
+        return success;
     }
 
     /// <summary />

src/Core/Components/DateTime/FluentCalendarBase.cs

@@ -7,7 +7,7 @@
 
 namespace Microsoft.FluentUI.AspNetCore.Components;
 
-public abstract class FluentCalendarBase : FluentInputBase<DateTime?>
+public abstract class FluentCalendarBase : FluentInputBase<DateTime?> , ICultureSensitiveComponent, IStringParsableComponent
 {
     /// <summary>
     /// Gets or sets the culture of the component.
@@ -16,6 +16,10 @@ public abstract class FluentCalendarBase : FluentInputBase<DateTime?>
     [Parameter]
     public virtual CultureInfo Culture { get; set; } = CultureInfo.CurrentCulture;
 
+    /// <inheritdoc/>
+    [Parameter]
+    public virtual string ParsingErrorMessage { get; set; } = "The {0} field must have a valid format.";
+
     /// <summary>
     /// Function to know if a specific day must be disabled.
     /// </summary>

src/Core/Components/DateTime/FluentDatePicker.razor.cs

@@ -145,10 +145,9 @@ protected override bool TryParseValueFromString(string? value, out DateTime? res
             value = new DateTime(year, 1, 1).ToString(Culture.DateTimeFormat.ShortDatePattern);
         }
 
-        BindConverter.TryConvertTo(value, Culture, out result);
-
-        validationErrorMessage = null;
-        return true;
+        bool success = BindConverter.TryConvertTo(value, Culture, out result);
+        validationErrorMessage = success ? null : string.Format(ParsingErrorMessage, FieldDisplayName);
+        return success;
     }
 
     private string PlaceholderAccordingToView()

src/Core/Components/List/ListComponentBase.razor.cs

@@ -17,7 +17,7 @@ namespace Microsoft.FluentUI.AspNetCore.Components;
 /// Component that provides a list of options.
 /// </summary>
 /// <typeparam name="TOption"></typeparam>
-public abstract partial class ListComponentBase<TOption> : FluentInputBase<string?>, IAsyncDisposable where TOption : notnull
+public abstract partial class ListComponentBase<TOption> : FluentInputBase<string?>, IAsyncDisposable, IStringParsableComponent where TOption : notnull
 {
     private const string JAVASCRIPT_FILE = "./_content/Microsoft.FluentUI.AspNetCore.Components/Components/List/ListComponentBase.razor.js";
 
@@ -212,6 +212,10 @@ protected string? InternalValue
     [Parameter]
     public Expression<Func<IEnumerable<TOption>>>? SelectedOptionsExpression { get; set; }
 
+    /// <inheritdoc/>
+    [Parameter]
+    public string ParsingErrorMessage { get; set; } = "The {0} field must be a (valid) number.";
+
     /// <summary />
     protected ListComponentBase()
     {

src/Core/Components/NumberField/FluentNumberField.razor.cs

@@ -10,7 +10,7 @@
 
 namespace Microsoft.FluentUI.AspNetCore.Components;
 
-public partial class FluentNumberField<TValue> : FluentInputBase<TValue>, IAsyncDisposable
+public partial class FluentNumberField<TValue> : FluentInputBase<TValue>, IAsyncDisposable, IStringParsableComponent
 {
     private const string JAVASCRIPT_FILE = "./_content/Microsoft.FluentUI.AspNetCore.Components/Components/TextField/FluentTextField.razor.js";
 
@@ -86,12 +86,6 @@ public partial class FluentNumberField<TValue> : FluentInputBase<TValue>, IAsync
     [Parameter]
     public string? AutoComplete { get; set; }
 
-    /// <summary>
-    /// Gets or sets the error message to show when the field can not be parsed.
-    /// </summary>
-    [Parameter]
-    public string ParsingErrorMessage { get; set; } = "The {0} field must be a (valid) number.";
-
     /// <summary>
     /// Gets or sets the content to be rendered inside the component.
     /// </summary>
@@ -105,6 +99,10 @@ public partial class FluentNumberField<TValue> : FluentInputBase<TValue>, IAsync
     [Parameter]
     public bool UseTypeConstraints { get; set; }
 
+    /// <inheritdoc/>
+    [Parameter]
+    public string ParsingErrorMessage { get; set; } = "The {0} field must be a (valid) number.";
+
     private static readonly string _stepAttributeValue = GetStepAttributeValue();
 
     // If type constraints is true and min is null, set min to the minimum value of TValue.

src/Core/Components/Radio/FluentRadioGroup.razor.cs

@@ -15,7 +15,7 @@ namespace Microsoft.FluentUI.AspNetCore.Components;
 /// </summary>
 
 [CascadingTypeParameter(nameof(TValue))]
-public partial class FluentRadioGroup<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] TValue> : FluentInputBase<TValue>
+public partial class FluentRadioGroup<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] TValue> : FluentInputBase<TValue>, IStringParsableComponent
 {
     private readonly string _defaultGroupName = Identifier.NewId();
     private FluentRadioContext? _context;
@@ -40,6 +40,10 @@ public FluentRadioGroup()
     [CascadingParameter]
     private FluentRadioContext? CascadedContext { get; set; }
 
+    /// <inheritdoc/>
+    [Parameter]
+    public string ParsingErrorMessage { get; set; } = "The {0} field must be a (valid) number.";
+
     /// <inheritdoc />
     protected override void OnParametersSet()
     {

src/Core/Components/Rating/FluentRating.razor.cs

@@ -10,7 +10,7 @@
 
 namespace Microsoft.FluentUI.AspNetCore.Components;
 
-public partial class FluentRating : FluentInputBase<int>
+public partial class FluentRating : FluentInputBase<int>, IStringParsableComponent
 {
     private bool _updatingCurrentValue = false;
     private int? _hoverValue = null;
@@ -74,6 +74,10 @@ public partial class FluentRating : FluentInputBase<int>
     [Parameter]
     public EventCallback<int?> OnHoverValueChanged { get; set; }
 
+    /// <inheritdoc/>
+    [Parameter]
+    public string ParsingErrorMessage { get; set; } = "The {0} field must be a number.";
+
     /// <summary />
     private string GroupName => Id ?? $"rating-{Id}";
 
@@ -90,8 +94,7 @@ protected override bool TryParseValueFromString(string? value, [MaybeNullWhen(fa
         }
         else
         {
-            validationErrorMessage = string.Format(CultureInfo.InvariantCulture,
-                                                   "The {0} field must be a number.",
+            validationErrorMessage = string.Format(ParsingErrorMessage,
                                                    FieldBound ? FieldIdentifier.FieldName : UnknownBoundField);
             return false;
         }

src/Core/Extensions/FluentInputExtensions.cs

@@ -10,13 +10,15 @@ namespace Microsoft.FluentUI.AspNetCore.Components.Extensions;
 internal static class FluentInputExtensions
 {
 
-    public static bool TryParseSelectableValueFromString<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] TValue>(
-        this FluentInputBase<TValue> input, string? value,
+    public static bool TryParseSelectableValueFromString<TInput, [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] TValue>(
+        this TInput input, string? value,
         [MaybeNullWhen(false)] out TValue result,
-        [NotNullWhen(false)] out string? validationErrorMessage)
+        [NotNullWhen(false)] out string? validationErrorMessage) where TInput : FluentInputBase<TValue>, IStringParsableComponent
     {
         try
         {
+            var culture = (input as ICultureSensitiveComponent)?.Culture ?? CultureInfo.CurrentCulture;
+
             // We special-case bool values because BindConverter reserves bool conversion for conditional attributes.
             if (typeof(TValue) == typeof(bool))
             {
@@ -34,15 +36,15 @@ internal static class FluentInputExtensions
                     return true;
                 }
             }
-            else if (BindConverter.TryConvertTo<TValue>(value, CultureInfo.CurrentCulture, out var parsedValue))
+            else if (BindConverter.TryConvertTo<TValue>(value, culture, out var parsedValue))
             {
                 result = parsedValue;
                 validationErrorMessage = null;
                 return true;
             }
 
             result = default;
-            validationErrorMessage = $"The {input.DisplayName ?? (input.FieldBound ? input.FieldIdentifier.FieldName : input.UnknownBoundField)} field is not valid.";
+            validationErrorMessage = string.Format(input.ParsingErrorMessage, input.FieldDisplayName);
             return false;
         }
         catch (InvalidOperationException ex)

tests/Core/DateTime/FluentDatePickerTests.cs

@@ -2,6 +2,7 @@
 // This file is licensed to you under the MIT License.
 // ------------------------------------------------------------------------
 
+using System.Diagnostics.CodeAnalysis;
 using System.Globalization;
 using Bunit;
 using Microsoft.AspNetCore.Components;
@@ -292,4 +293,42 @@ public void FluentDatePicker_OnDoubleClickEventTriggers()
         // Assert
         Assert.Equal(expected, actual);
     }
+
+    [Theory]
+    [InlineData("02-22-2000", "en-GB", "02/22/2000")]
+    [InlineData("02-22-2000", "nl-BE", null)]
+    [InlineData("22-12-2000", "nl-BE", "22/12/2000")]
+    [InlineData("02/22/2000", "en-GB", "02/22/2000")]
+    [InlineData("abc", "en-GB", null)]
+    [InlineData("02022000", "en-GB", null)]
+    public void FluentDatePicker_TryParseValueFromString(string? value, string? cultureName, string? expectedValue)
+    {
+        // Arrange
+        var picker = new TestDatePicker();
+        var culture = cultureName != null ? CultureInfo.GetCultureInfo(cultureName) : CultureInfo.InvariantCulture;
+
+        // Act
+        picker.Culture = culture;
+        var successfullParse = picker.CallTryParseValueFromString(value, out var resultDate, out var validationErrorMessage);
+
+        // Assert
+        if (successfullParse)
+        {
+            Assert.Equal(expectedValue, resultDate?.ToString(culture.DateTimeFormat.ShortDatePattern, culture));
+        }
+        else
+        {
+            Assert.Null(resultDate);
+            Assert.NotNull(validationErrorMessage);
+        }
+    }
+
+    // Temporary class to expose protected method
+    private class TestDatePicker : FluentDatePicker
+    {
+        public bool CallTryParseValueFromString(string? value, out System.DateTime? result, [NotNullWhen(false)] out string? validationErrorMessage)
+        {
+            return base.TryParseValueFromString(value, out result, out validationErrorMessage);
+        }
+    }
 }