Added TryGetValue<T> for Properties - fix #21343

src/EFCore/ChangeTracking/PropertyValues.cs

@@ -148,6 +148,28 @@ public virtual IEntityType EntityType
         /// <returns> The value of the property. </returns>
         public abstract TValue GetValue<TValue>([NotNull] string propertyName);
 
+        /// <summary>
+        ///     Safely gets the value of the property just like using the indexed property getter but
+        ///     typed to the type of the generic parameter.
+        ///     If property exists it return into the out parameter, otherwise the default value of TValue
+        /// </summary>
+        /// <typeparam name="TValue"> The type of the property. </typeparam>
+        /// <param name="propertyName"> The property name. </param>
+        /// <param name="value"> The property value if any. </param>
+        /// <returns> True if the property exists, otherwise false. </returns>
+        public bool TryGetValue<TValue>([NotNull] string propertyName, out TValue value)
+        {
+            var property = EntityType.FindProperty(propertyName);
+            if (propertyName != null)
+            {
+                value = this.GetValue<TValue>(propertyName);
+                return true;
+            }
+
+            value = default(TValue);
+            return false;
+        }
+
         /// <summary>
         ///     Gets the value of the property just like using the indexed property getter but
         ///     typed to the type of the generic parameter.

test/EFCore.Tests/ChangeTracking/Internal/PropertyValuesTest.cs

@@ -0,0 +1,94 @@
+// Copyright (c) .NET Foundation. All rights reserved.
+// Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.
+
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using Xunit;
+
+namespace Microsoft.EntityFrameworkCore.ChangeTracking.Internal
+{
+    public class PropertyValuesTest
+    {
+        [ConditionalFact]
+        public void Can_safely_get_originalvalue_and_currentvalue_with_tryget()
+        {
+            // Arrange
+            const string NameValue = "Simple Name";
+            const string NewNameValue = "A New Name";
+
+            using var ctx = new CurrentValuesDb();
+            var entity = ctx.SimpleEntities.Add(new SimpleEntity { Name = NameValue });
+            ctx.SaveChanges();
+
+            entity.Entity.Name = NewNameValue;
+
+            // Act
+            var current = entity.CurrentValues.TryGetValue<string>("Name", out var currentName);
+            var original = entity.OriginalValues.TryGetValue<string>("Name", out var originalName);
+
+            // Assert
+            Assert.True(current);
+            Assert.True(original);
+
+            Assert.Equal(NameValue, originalName);
+            Assert.Equal(NewNameValue, currentName);
+        }
+
+        [ConditionalFact]
+        public void Should_not_throw_error_when_property_do_not_exist()
+        {
+            // Arrange
+            const string NameValue = "Simple Name";
+            const string NewNameValue = "A New Name";
+
+            using var ctx = new CurrentValuesDb();
+            var entity = ctx.SimpleEntities.Add(new SimpleEntity { Name = NameValue });
+            ctx.SaveChanges();
+
+            entity.Entity.Name = NewNameValue;
+
+            // Act
+            var current = entity.CurrentValues.TryGetValue<string>("Non_Existent_Property", out var non_existent_current);
+            var original = entity.OriginalValues.TryGetValue<string>("Non_Existent_Property", out var non_existent_original);
+
+            // Assert
+            Assert.False(current);
+            Assert.False(original);
+
+            Assert.Null(non_existent_current);
+            Assert.Null(non_existent_original);
+        }
+
+        private class CurrentValuesDb : DbContext
+        {
+            public DbSet<SimpleEntity> SimpleEntities { get; set; }
+
+            protected internal override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
+            {
+                optionsBuilder.UseInMemoryDatabase("DB1");
+            }
+        }
+
+        private class SimpleEntity
+        {
+            public int Id { get; set; }
+
+            public string Name { get; set; }
+
+            public IEnumerable<RelatedEntity> RelatedEntities { get; set; }
+
+        }
+
+        private class RelatedEntity
+        {
+            public int Id { get; set; }
+
+            public int? SimpleEntityId { get; set; }
+
+            public SimpleEntity SimpleEntity { get; set; }
+
+            public string Name {get; set;}
+        }
+    }
+}