Switched from cs to XML on csproj files
These files are not used as project files, just sample files that are listed in the chapter.
DELETE
src/Chapter01/Listing01.02.SampleNETCoreConsoleProjectFile.cs
-#region INCLUDE
-<Project Sdk="Microsoft.NET.Sdk">
- <PropertyGroup>
- <OutputType>Exe</OutputType>
- <TargetFramework>net7.0</TargetFramework>
- </PropertyGroup>
-</Project>
-#endregion INCLUDE
\ No newline at end of file

ADD
src/Chapter01/Listing01.02.SampleNETCoreConsoleProjectFile.xml
+<!--#region INCLUDE-->
+<Project Sdk="Microsoft.NET.Sdk">
+ <PropertyGroup>
+ <OutputType>Exe</OutputType>
+ <TargetFramework>net7.0</TargetFramework>
+ <ImplicitUsings>enable</ImplicitUsings>
+ <Nullable>enable</Nullable>
+ </PropertyGroup>
+</Project>
+<!--#endregion INCLUDE-->
\ No newline at end of file

RENAME
src/Chapter03/Listing03.03.EnablingNullableProjectWide.cs
src/Chapter03/Listing03.03.EnablingNullableProjectWide.xml
-#region INCLUDE
+<!--#region INCLUDE-->
<Project Sdk="Microsoft.NET.Sdk">
<PropertyGroup>
<OutputType>Exe</OutputType>
<Nullable>enable</Nullable>
</PropertyGroup>
</Project>
-#endregion INCLUDE
+<!--#endregion INCLUDE-->

Switched from cs to XML on csproj files

These files are not used as project files, just sample files that are listed in the chapter.