fixed: 改回.net5

CSserver/BossServer/BossServer.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>

CSserver/Lib1/Lib1.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>

CSserver/PBReferens/PBReferens.csproj

@@ -1,7 +1,7 @@
 <Project Sdk="Microsoft.NET.Sdk">
 
   <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
   <Target Name="PreBuild" BeforeTargets="PreBuildEvent">

CSserver/clientTest/clientTest.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
     <StartupObject>clientTest.chat.Program</StartupObject>
   </PropertyGroup>
 

CSserver/csserver/ChatServer.csproj

@@ -2,7 +2,7 @@
 
   <PropertyGroup>
     <OutputType>Exe</OutputType>
-    <TargetFramework>net6.0</TargetFramework>
+    <TargetFramework>net5.0</TargetFramework>
   </PropertyGroup>
 
   <ItemGroup>