Enable nullable

NatTypeTester-Console/NatTypeTester_Console.csproj

@@ -1,9 +1,11 @@
-<Project Sdk="Microsoft.NET.Sdk">
+<Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFrameworks>net472;net48;netcoreapp3.1</TargetFrameworks>
-    <RootNamespace>NatTypeTester_Console</RootNamespace>
+    <TargetFrameworks>net48;net5.0</TargetFrameworks>
+    <RootNamespace>NatTypeTester</RootNamespace>
+    <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>

NatTypeTester/NatTypeTester.csproj

@@ -6,6 +6,7 @@
     <UseWPF>true</UseWPF>
     <ApplicationIcon>icon.ico</ApplicationIcon>
     <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
     <Version>3.3</Version>
     <Authors>HMBSbige</Authors>
   </PropertyGroup>

STUN/STUN.csproj

@@ -3,6 +3,7 @@
   <PropertyGroup>
     <TargetFramework>netstandard2.0</TargetFramework>
     <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
   </PropertyGroup>
 
   <ItemGroup>

UnitTest/UnitTest.csproj

@@ -1,16 +1,12 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>netcoreapp3.1</TargetFramework>
-
+    <TargetFramework>net5.0</TargetFramework>
+    <LangVersion>latest</LangVersion>
+    <Nullable>enable</Nullable>
     <IsPackable>false</IsPackable>
   </PropertyGroup>
 
-  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|AnyCPU'">
-    <PlatformTarget>AnyCPU</PlatformTarget>
-    <Prefer32Bit>false</Prefer32Bit>
-  </PropertyGroup>
-
   <ItemGroup>
     <PackageReference Include="Microsoft.NET.Test.Sdk" Version="16.5.0" />
     <PackageReference Include="MSTest.TestAdapter" Version="2.1.0" />