Issue / .NET 10 / Field Keyword

csharp/CSharp/Assignments.cs

@@ -0,0 +1,25 @@
+using Microsoft.Extensions.Logging;
+
+namespace CSharp;
+
+public class Assignments(ILogger<Assignments> _logger)
+{
+    public Data? NullableData { get; set; } = default;
+
+    public void NullConditional()
+    {
+        NullableData?.Value = "test";
+
+        _logger.LogInformation($"Before data is created, NullableData: {NullableData}");
+
+        NullableData = new();
+        NullableData?.Value = "test";
+
+        _logger.LogInformation($"After data is created, NullableData: {NullableData} - Value: {NullableData?.Value}");
+    }
+
+    public class Data
+    {
+        public string? Value { get; set; }
+    }
+}

csharp/CSharp/CollectionExpressions.cs

@@ -34,6 +34,19 @@ public void CollectionInitialization()
         _logger.LogInformation($"Array initialization with spread element and members: {string.Join(',', anotherIntCollection)}");
     }
 
+    public void Conversions()
+    {
+        int[] numbers = [1, 2, 3];
+
+        // T[] -> Span<T>
+        Span<int> spanNumbers = numbers;
+        _logger.LogInformation($"Implicit Conversion int[] -> span<int>: {string.Join(',', spanNumbers.ToArray())}");
+
+        // T[] -> ReadOnlySpan<T>
+        ReadOnlySpan<int> readOnlyNumbers = numbers;
+        _logger.LogInformation($"Implicit Conversion int[] -> ReadOnlySpan<int>: {string.Join(',', readOnlyNumbers.ToArray())}");
+    }
+
     public void CallMethods()
     {
         SomeMethod("arg1", "arg2", "arg3");

csharp/CSharp/LambdaParameters.cs

@@ -2,7 +2,7 @@
 
 namespace CSharp;
 
-public class LambdaParameters(ILogger<CollectionExpressions> _logger)
+public class LambdaParameters(ILogger<LambdaParameters> _logger)
 {
     public void OptionalParameters()
     {
@@ -32,4 +32,14 @@ void Params(params int[] values) { }
         optional();
         @params();
     }
+
+    private delegate bool TryParse<T>(string text, out T result);
+
+    public void ParameterModifiersWithoutTypes()
+    {
+        // Lambdas support modifiers (ref/in/out/scoped/ref readonly) without explicit parameter types when the target delegate type is known
+        TryParse<int> parse = (text, out result) => int.TryParse(text, out result);
+
+        _logger.LogInformation($"(text, out result) => int.TryParse: ok={parse("42", out int value)}, result={value}");
+    }
 }

csharp/CSharp/Program.cs

@@ -4,10 +4,12 @@
 
 var serviceCollection = new ServiceCollection();
 
+serviceCollection.AddSingleton<Assignments>();
 serviceCollection.AddSingleton<CollectionExpressions>();
 serviceCollection.AddSingleton<EncodingDecoding>();
 serviceCollection.AddSingleton<LambdaParameters>();
 serviceCollection.AddSingleton<Params>();
+serviceCollection.AddSingleton<PropertiesAndFields>();
 
 serviceCollection.AddLogging(options =>
 {
@@ -17,19 +19,27 @@
 
 var serviceProvider = serviceCollection.BuildServiceProvider();
 
+var assignments = serviceProvider.GetRequiredService<Assignments>();
 var collectionExpressions = serviceProvider.GetRequiredService<CollectionExpressions>();
 var encodingDecoding = serviceProvider.GetRequiredService<EncodingDecoding>();
 var lambdaParameters = serviceProvider.GetRequiredService<LambdaParameters>();
 var @params = serviceProvider.GetRequiredService<Params>();
+var propertiesAndFields = serviceProvider.GetRequiredService<PropertiesAndFields>();
 
 @params.Use();
 
+assignments.NullConditional();
+
 collectionExpressions.EmptyCollectionInitialization();
 collectionExpressions.CollectionInitialization();
+collectionExpressions.Conversions();
 collectionExpressions.CallMethods();
 
 lambdaParameters.OptionalParameters();
 lambdaParameters.ParamsArrayParameters();
 lambdaParameters.NewAcceptedBehavior();
+lambdaParameters.ParameterModifiersWithoutTypes();
+
+encodingDecoding.RunShowCases();
 
-encodingDecoding.RunShowCases();
+propertiesAndFields.FieldKeyword();

csharp/CSharp/PropertiesAndFields.cs

@@ -0,0 +1,18 @@
+using Microsoft.Extensions.Logging;
+
+namespace CSharp;
+
+public class PropertiesAndFields(ILogger<PropertiesAndFields> _logger)
+{
+    string _filed = "field";
+
+    public string WithOutFieldKeyword { get => _filed; set => _filed = value; }
+    public string WithFieldKeyword { get; set => field = value.Trim(); } = "WithField";
+
+    public void FieldKeyword()
+    {
+        _logger.LogInformation($"_field => '{_filed}'");
+        _logger.LogInformation($"WithOutFieldKeyword => '{WithOutFieldKeyword}'");
+        _logger.LogInformation($"WithFieldKeyword => '{WithFieldKeyword}'");
+    }
+}

csharp/README.md

@@ -5,7 +5,9 @@ projects.
 
 What we have learned and implemented so far are the following.
 
+- Assignments
 - Collection expressions
 - Different Params type usage
 - Encoding Decoding
 - Lambda Parameters
+- Properties and fields