Fix signature for nullability (#10738)

StephaneDelcroix · web-flow · commit bc434e633029 · 2024-12-09T19:03:51.000Z
diff --git a/snippets/csharp/System/EventArgs/Overview/Project.csproj b/snippets/csharp/System/EventArgs/Overview/Project.csproj
@@ -0,0 +1,9 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <nullable>enable</nullable>
+  </PropertyGroup>
+
+</Project>
diff --git a/snippets/csharp/System/EventArgs/Overview/program.cs b/snippets/csharp/System/EventArgs/Overview/program.cs
@@ -0,0 +1,4 @@
+﻿ConsoleApplication1.Program1.Main();
+ConsoleApplication2.Program2.Main();
+ConsoleApplication3.Program3.Main();
+ConsoleApplication4.Program4.Main();
diff --git a/snippets/csharp/System/EventArgs/Overview/programnodata.cs b/snippets/csharp/System/EventArgs/Overview/programnodata.cs
@@ -3,11 +3,11 @@
 
 namespace ConsoleApplication1
 {
-    class Program
+    public class Program1
     {
-        static void Main(string[] args)
+        public static void Main()
         {
-            Counter c = new Counter(new Random().Next(10));
+            Counter c = new(new Random().Next(10));
             c.ThresholdReached += c_ThresholdReached;
 
             Console.WriteLine("press 'a' key to increase total");
@@ -18,7 +18,7 @@ static void Main(string[] args)
             }
         }
 
-        static void c_ThresholdReached(object sender, EventArgs e)
+        static void c_ThresholdReached(object? sender, EventArgs e)
         {
             Console.WriteLine("The threshold was reached.");
             Environment.Exit(0);
@@ -27,33 +27,29 @@ static void c_ThresholdReached(object sender, EventArgs e)
 
     class Counter
     {
-        private int threshold;
-        private int total;
+        private readonly int _threshold;
+        private int _total;
 
         public Counter(int passedThreshold)
         {
-            threshold = passedThreshold;
+            _threshold = passedThreshold;
         }
 
         public void Add(int x)
         {
-            total += x;
-            if (total >= threshold)
+            _total += x;
+            if (_total >= _threshold)
             {
                 OnThresholdReached(EventArgs.Empty);
             }
         }
 
         protected virtual void OnThresholdReached(EventArgs e)
         {
-            EventHandler handler = ThresholdReached;
-            if (handler != null)
-            {
-                handler(this, e);
-            }
+            ThresholdReached?.Invoke(this, e);
         }
 
-        public event EventHandler ThresholdReached;
+        public event EventHandler? ThresholdReached;
     }
 }
 // </snippet5>
diff --git a/snippets/csharp/System/EventArgs/Overview/programtruncated.cs b/snippets/csharp/System/EventArgs/Overview/programtruncated.cs
@@ -1,19 +1,19 @@
 ﻿using System;
 
-namespace ConsoleApplication1
+namespace ConsoleApplication2
 {
     // <snippet2>
-    class Program
+    public class Program2
     {
-        static void Main()
+        public static void Main()
         {
             var c = new Counter();
             c.ThresholdReached += c_ThresholdReached;
 
             // provide remaining implementation for the class
         }
 
-        static void c_ThresholdReached(object sender, EventArgs e)
+        static void c_ThresholdReached(object? sender, EventArgs e)
         {
             Console.WriteLine("The threshold was reached.");
         }
@@ -23,11 +23,11 @@ static void c_ThresholdReached(object sender, EventArgs e)
     // <snippet1>
     class Counter
     {
-        public event EventHandler ThresholdReached;
+        public event EventHandler? ThresholdReached;
 
         protected virtual void OnThresholdReached(EventArgs e)
         {
-            EventHandler handler = ThresholdReached;
+            EventHandler? handler = ThresholdReached;
             handler?.Invoke(this, e);
         }
 
diff --git a/snippets/csharp/System/EventArgs/Overview/programwithdata.cs b/snippets/csharp/System/EventArgs/Overview/programwithdata.cs
@@ -1,13 +1,13 @@
 ﻿// <snippet6>
 using System;
 
-namespace ConsoleApplication1
+namespace ConsoleApplication3
 {
-    class Program
+    public class Program3
     {
-        static void Main(string[] args)
+        public static void Main()
         {
-            Counter c = new Counter(new Random().Next(10));
+            Counter c = new(new Random().Next(10));
             c.ThresholdReached += c_ThresholdReached;
 
             Console.WriteLine("press 'a' key to increase total");
@@ -18,7 +18,7 @@ static void Main(string[] args)
             }
         }
 
-        static void c_ThresholdReached(object sender, ThresholdReachedEventArgs e)
+        static void c_ThresholdReached(object? sender, ThresholdReachedEventArgs e)
         {
             Console.WriteLine("The threshold of {0} was reached at {1}.", e.Threshold,  e.TimeReached);
             Environment.Exit(0);
@@ -27,36 +27,34 @@ static void c_ThresholdReached(object sender, ThresholdReachedEventArgs e)
 
     class Counter
     {
-        private int threshold;
-        private int total;
+        private readonly int _threshold;
+        private int _total;
 
         public Counter(int passedThreshold)
         {
-            threshold = passedThreshold;
+            _threshold = passedThreshold;
         }
 
         public void Add(int x)
         {
-            total += x;
-            if (total >= threshold)
+            _total += x;
+            if (_total >= _threshold)
             {
-                ThresholdReachedEventArgs args = new ThresholdReachedEventArgs();
-                args.Threshold = threshold;
-                args.TimeReached = DateTime.Now;
+                ThresholdReachedEventArgs args = new()
+                {
+                    Threshold = _threshold,
+                    TimeReached = DateTime.Now
+                };
                 OnThresholdReached(args);
             }
         }
 
         protected virtual void OnThresholdReached(ThresholdReachedEventArgs e)
         {
-            EventHandler<ThresholdReachedEventArgs> handler = ThresholdReached;
-            if (handler != null)
-            {
-                handler(this, e);
-            }
+            ThresholdReached?.Invoke(this, e);
         }
 
-        public event EventHandler<ThresholdReachedEventArgs> ThresholdReached;
+        public event EventHandler<ThresholdReachedEventArgs>? ThresholdReached;
     }
 
     public class ThresholdReachedEventArgs : EventArgs
diff --git a/snippets/csharp/System/EventArgs/Overview/programwithdelegate.cs b/snippets/csharp/System/EventArgs/Overview/programwithdelegate.cs
@@ -1,13 +1,13 @@
 ﻿// <snippet7>
 using System;
 
-namespace ConsoleApplication1
+namespace ConsoleApplication4
 {
-    class Program
+    class Program4
     {
-        static void Main(string[] args)
+        public static void Main()
         {
-            Counter c = new Counter(new Random().Next(10));
+            Counter c = new(new Random().Next(10));
             c.ThresholdReached += c_ThresholdReached;
 
             Console.WriteLine("press 'a' key to increase total");
@@ -18,7 +18,7 @@ static void Main(string[] args)
             }
         }
 
-        static void c_ThresholdReached(Object sender, ThresholdReachedEventArgs e)
+        public static void c_ThresholdReached(object? sender, ThresholdReachedEventArgs e)
         {
             Console.WriteLine("The threshold of {0} was reached at {1}.", e.Threshold, e.TimeReached);
             Environment.Exit(0);
@@ -27,36 +27,34 @@ static void c_ThresholdReached(Object sender, ThresholdReachedEventArgs e)
 
     class Counter
     {
-        private int threshold;
-        private int total;
+        private readonly int _threshold;
+        private int _total;
 
         public Counter(int passedThreshold)
         {
-            threshold = passedThreshold;
+            _threshold = passedThreshold;
         }
 
         public void Add(int x)
         {
-            total += x;
-            if (total >= threshold)
+            _total += x;
+            if (_total >= _threshold)
             {
-                ThresholdReachedEventArgs args = new ThresholdReachedEventArgs();
-                args.Threshold = threshold;
-                args.TimeReached = DateTime.Now;
+                ThresholdReachedEventArgs args = new()
+                {
+                    Threshold = _threshold,
+                    TimeReached = DateTime.Now
+                };
                 OnThresholdReached(args);
             }
         }
 
         protected virtual void OnThresholdReached(ThresholdReachedEventArgs e)
         {
-            ThresholdReachedEventHandler handler = ThresholdReached;
-            if (handler != null)
-            {
-                handler(this, e);
-            }
+            ThresholdReached?.Invoke(this, e);
         }
 
-        public event ThresholdReachedEventHandler ThresholdReached;
+        public event ThresholdReachedEventHandler? ThresholdReached;
     }
 
     public class ThresholdReachedEventArgs : EventArgs
@@ -65,6 +63,6 @@ public class ThresholdReachedEventArgs : EventArgs
         public DateTime TimeReached { get; set; }
     }
 
-    public delegate void ThresholdReachedEventHandler(Object sender, ThresholdReachedEventArgs e);
+    public delegate void ThresholdReachedEventHandler(object sender, ThresholdReachedEventArgs e);
 }
 // </snippet7>

Original file line number	Diff line number	Diff line change
`@@ -3,11 +3,11 @@`
`3`	`3`
`4`	`4`	`namespace ConsoleApplication1`
`5`	`5`	`{`
`6`		`- class Program`
	`6`	`+ public class Program1`
`7`	`7`	`{`
`8`		`- static void Main(string[] args)`
	`8`	`+ public static void Main()`
`9`	`9`	`{`
`10`		`- Counter c = new Counter(new Random().Next(10));`
	`10`	`+ Counter c = new(new Random().Next(10));`
`11`	`11`	`c.ThresholdReached += c_ThresholdReached;`
`12`	`12`
`13`	`13`	`Console.WriteLine("press 'a' key to increase total");`
`@@ -18,7 +18,7 @@ static void Main(string[] args)`
`18`	`18`	`}`
`19`	`19`	`}`
`20`	`20`
`21`		`- static void c_ThresholdReached(object sender, EventArgs e)`
	`21`	`+ static void c_ThresholdReached(object? sender, EventArgs e)`
`22`	`22`	`{`
`23`	`23`	`Console.WriteLine("The threshold was reached.");`
`24`	`24`	`Environment.Exit(0);`
`@@ -27,33 +27,29 @@ static void c_ThresholdReached(object sender, EventArgs e)`
`27`	`27`
`28`	`28`	`class Counter`
`29`	`29`	`{`
`30`		`- private int threshold;`
`31`		`- private int total;`
	`30`	`+ private readonly int _threshold;`
	`31`	`+ private int _total;`
`32`	`32`
`33`	`33`	`public Counter(int passedThreshold)`
`34`	`34`	`{`
`35`		`- threshold = passedThreshold;`
	`35`	`+ _threshold = passedThreshold;`
`36`	`36`	`}`
`37`	`37`
`38`	`38`	`public void Add(int x)`
`39`	`39`	`{`
`40`		`- total += x;`
`41`		`- if (total >= threshold)`
	`40`	`+ _total += x;`
	`41`	`+ if (_total >= _threshold)`
`42`	`42`	`{`
`43`	`43`	`OnThresholdReached(EventArgs.Empty);`
`44`	`44`	`}`
`45`	`45`	`}`
`46`	`46`
`47`	`47`	`protected virtual void OnThresholdReached(EventArgs e)`
`48`	`48`	`{`
`49`		`- EventHandler handler = ThresholdReached;`
`50`		`- if (handler != null)`
`51`		`- {`
`52`		`- handler(this, e);`
`53`		`- }`
	`49`	`+ ThresholdReached?.Invoke(this, e);`
`54`	`50`	`}`
`55`	`51`
`56`		`- public event EventHandler ThresholdReached;`
	`52`	`+ public event EventHandler? ThresholdReached;`
`57`	`53`	`}`
`58`	`54`	`}`
`59`	`55`	`// </snippet5>`
Original file line number	Diff line number	Diff line change
`@@ -1,19 +1,19 @@`
`1`	`1`	`using System;`
`2`	`2`
`3`		`-namespace ConsoleApplication1`
	`3`	`+namespace ConsoleApplication2`
`4`	`4`	`{`
`5`	`5`	`// <snippet2>`
`6`		`- class Program`
	`6`	`+ public class Program2`
`7`	`7`	`{`
`8`		`- static void Main()`
	`8`	`+ public static void Main()`
`9`	`9`	`{`
`10`	`10`	`var c = new Counter();`
`11`	`11`	`c.ThresholdReached += c_ThresholdReached;`
`12`	`12`
`13`	`13`	`// provide remaining implementation for the class`
`14`	`14`	`}`
`15`	`15`
`16`		`- static void c_ThresholdReached(object sender, EventArgs e)`
	`16`	`+ static void c_ThresholdReached(object? sender, EventArgs e)`
`17`	`17`	`{`
`18`	`18`	`Console.WriteLine("The threshold was reached.");`
`19`	`19`	`}`
`@@ -23,11 +23,11 @@ static void c_ThresholdReached(object sender, EventArgs e)`
`23`	`23`	`// <snippet1>`
`24`	`24`	`class Counter`
`25`	`25`	`{`
`26`		`- public event EventHandler ThresholdReached;`
	`26`	`+ public event EventHandler? ThresholdReached;`
`27`	`27`
`28`	`28`	`protected virtual void OnThresholdReached(EventArgs e)`
`29`	`29`	`{`
`30`		`- EventHandler handler = ThresholdReached;`
	`30`	`+ EventHandler? handler = ThresholdReached;`
`31`	`31`	`handler?.Invoke(this, e);`
`32`	`32`	`}`
`33`	`33`
Original file line number	Diff line number	Diff line change
`@@ -1,13 +1,13 @@`
`1`	`1`	`// <snippet6>`
`2`	`2`	`using System;`
`3`	`3`
`4`		`-namespace ConsoleApplication1`
	`4`	`+namespace ConsoleApplication3`
`5`	`5`	`{`
`6`		`- class Program`
	`6`	`+ public class Program3`
`7`	`7`	`{`
`8`		`- static void Main(string[] args)`
	`8`	`+ public static void Main()`
`9`	`9`	`{`
`10`		`- Counter c = new Counter(new Random().Next(10));`
	`10`	`+ Counter c = new(new Random().Next(10));`
`11`	`11`	`c.ThresholdReached += c_ThresholdReached;`
`12`	`12`
`13`	`13`	`Console.WriteLine("press 'a' key to increase total");`
`@@ -18,7 +18,7 @@ static void Main(string[] args)`
`18`	`18`	`}`
`19`	`19`	`}`
`20`	`20`
`21`		`- static void c_ThresholdReached(object sender, ThresholdReachedEventArgs e)`
	`21`	`+ static void c_ThresholdReached(object? sender, ThresholdReachedEventArgs e)`
`22`	`22`	`{`
`23`	`23`	`Console.WriteLine("The threshold of {0} was reached at {1}.", e.Threshold, e.TimeReached);`
`24`	`24`	`Environment.Exit(0);`
`@@ -27,36 +27,34 @@ static void c_ThresholdReached(object sender, ThresholdReachedEventArgs e)`
`27`	`27`
`28`	`28`	`class Counter`
`29`	`29`	`{`
`30`		`- private int threshold;`
`31`		`- private int total;`
	`30`	`+ private readonly int _threshold;`
	`31`	`+ private int _total;`
`32`	`32`
`33`	`33`	`public Counter(int passedThreshold)`
`34`	`34`	`{`
`35`		`- threshold = passedThreshold;`
	`35`	`+ _threshold = passedThreshold;`
`36`	`36`	`}`
`37`	`37`
`38`	`38`	`public void Add(int x)`
`39`	`39`	`{`
`40`		`- total += x;`
`41`		`- if (total >= threshold)`
	`40`	`+ _total += x;`
	`41`	`+ if (_total >= _threshold)`
`42`	`42`	`{`
`43`		`- ThresholdReachedEventArgs args = new ThresholdReachedEventArgs();`
`44`		`- args.Threshold = threshold;`
`45`		`- args.TimeReached = DateTime.Now;`
	`43`	`+ ThresholdReachedEventArgs args = new()`
	`44`	`+ {`
	`45`	`+ Threshold = _threshold,`
	`46`	`+ TimeReached = DateTime.Now`
	`47`	`+ };`
`46`	`48`	`OnThresholdReached(args);`
`47`	`49`	`}`
`48`	`50`	`}`
`49`	`51`
`50`	`52`	`protected virtual void OnThresholdReached(ThresholdReachedEventArgs e)`
`51`	`53`	`{`
`52`		`- EventHandler<ThresholdReachedEventArgs> handler = ThresholdReached;`
`53`		`- if (handler != null)`
`54`		`- {`
`55`		`- handler(this, e);`
`56`		`- }`
	`54`	`+ ThresholdReached?.Invoke(this, e);`
`57`	`55`	`}`
`58`	`56`
`59`		`- public event EventHandler<ThresholdReachedEventArgs> ThresholdReached;`
	`57`	`+ public event EventHandler<ThresholdReachedEventArgs>? ThresholdReached;`
`60`	`58`	`}`
`61`	`59`
`62`	`60`	`public class ThresholdReachedEventArgs : EventArgs`
Original file line number	Diff line number	Diff line change
`@@ -1,13 +1,13 @@`
`1`	`1`	`// <snippet7>`
`2`	`2`	`using System;`
`3`	`3`
`4`		`-namespace ConsoleApplication1`
	`4`	`+namespace ConsoleApplication4`
`5`	`5`	`{`
`6`		`- class Program`
	`6`	`+ class Program4`
`7`	`7`	`{`
`8`		`- static void Main(string[] args)`
	`8`	`+ public static void Main()`
`9`	`9`	`{`
`10`		`- Counter c = new Counter(new Random().Next(10));`
	`10`	`+ Counter c = new(new Random().Next(10));`
`11`	`11`	`c.ThresholdReached += c_ThresholdReached;`
`12`	`12`
`13`	`13`	`Console.WriteLine("press 'a' key to increase total");`
`@@ -18,7 +18,7 @@ static void Main(string[] args)`
`18`	`18`	`}`
`19`	`19`	`}`
`20`	`20`
`21`		`- static void c_ThresholdReached(Object sender, ThresholdReachedEventArgs e)`
	`21`	`+ public static void c_ThresholdReached(object? sender, ThresholdReachedEventArgs e)`
`22`	`22`	`{`
`23`	`23`	`Console.WriteLine("The threshold of {0} was reached at {1}.", e.Threshold, e.TimeReached);`
`24`	`24`	`Environment.Exit(0);`
`@@ -27,36 +27,34 @@ static void c_ThresholdReached(Object sender, ThresholdReachedEventArgs e)`
`27`	`27`
`28`	`28`	`class Counter`
`29`	`29`	`{`
`30`		`- private int threshold;`
`31`		`- private int total;`
	`30`	`+ private readonly int _threshold;`
	`31`	`+ private int _total;`
`32`	`32`
`33`	`33`	`public Counter(int passedThreshold)`
`34`	`34`	`{`
`35`		`- threshold = passedThreshold;`
	`35`	`+ _threshold = passedThreshold;`
`36`	`36`	`}`
`37`	`37`
`38`	`38`	`public void Add(int x)`
`39`	`39`	`{`
`40`		`- total += x;`
`41`		`- if (total >= threshold)`
	`40`	`+ _total += x;`
	`41`	`+ if (_total >= _threshold)`
`42`	`42`	`{`
`43`		`- ThresholdReachedEventArgs args = new ThresholdReachedEventArgs();`
`44`		`- args.Threshold = threshold;`
`45`		`- args.TimeReached = DateTime.Now;`
	`43`	`+ ThresholdReachedEventArgs args = new()`
	`44`	`+ {`
	`45`	`+ Threshold = _threshold,`
	`46`	`+ TimeReached = DateTime.Now`
	`47`	`+ };`
`46`	`48`	`OnThresholdReached(args);`
`47`	`49`	`}`
`48`	`50`	`}`
`49`	`51`
`50`	`52`	`protected virtual void OnThresholdReached(ThresholdReachedEventArgs e)`
`51`	`53`	`{`
`52`		`- ThresholdReachedEventHandler handler = ThresholdReached;`
`53`		`- if (handler != null)`
`54`		`- {`
`55`		`- handler(this, e);`
`56`		`- }`
	`54`	`+ ThresholdReached?.Invoke(this, e);`
`57`	`55`	`}`
`58`	`56`
`59`		`- public event ThresholdReachedEventHandler ThresholdReached;`
	`57`	`+ public event ThresholdReachedEventHandler? ThresholdReached;`
`60`	`58`	`}`
`61`	`59`
`62`	`60`	`public class ThresholdReachedEventArgs : EventArgs`
`@@ -65,6 +63,6 @@ public class ThresholdReachedEventArgs : EventArgs`
`65`	`63`	`public DateTime TimeReached { get; set; }`
`66`	`64`	`}`
`67`	`65`
`68`		`- public delegate void ThresholdReachedEventHandler(Object sender, ThresholdReachedEventArgs e);`
	`66`	`+ public delegate void ThresholdReachedEventHandler(object sender, ThresholdReachedEventArgs e);`
`69`	`67`	`}`
`70`	`68`	`// </snippet7>`