添加项目文件。

C#入门/Csharp入门.sln

@@ -0,0 +1,43 @@
+
+Microsoft Visual Studio Solution File, Format Version 12.00
+# Visual Studio Version 17
+VisualStudioVersion = 17.14.36202.13 d17.14
+MinimumVisualStudioVersion = 10.0.40219.1
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "test1", "test1\test1.csproj", "{431A94A0-24B2-497E-A1FE-693FA2EF350F}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Lesson1注释&输入输出", "lesson1\Lesson1注释&输入输出.csproj", "{C9D85F7A-86E5-4034-AA0B-F469E441F9C5}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Lesson1练习题", "Lession1练习题\Lesson1练习题.csproj", "{D965940D-E758-4A7C-977A-74E5793C593B}"
+EndProject
+Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Lesson2变量", "Lesson2变量\Lesson2变量.csproj", "{21CE6A7D-CC82-4F41-A28F-54D2E535FB3F}"
+EndProject
+Global
+	GlobalSection(SolutionConfigurationPlatforms) = preSolution
+		Debug|Any CPU = Debug|Any CPU
+		Release|Any CPU = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(ProjectConfigurationPlatforms) = postSolution
+		{431A94A0-24B2-497E-A1FE-693FA2EF350F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{431A94A0-24B2-497E-A1FE-693FA2EF350F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{431A94A0-24B2-497E-A1FE-693FA2EF350F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{431A94A0-24B2-497E-A1FE-693FA2EF350F}.Release|Any CPU.Build.0 = Release|Any CPU
+		{C9D85F7A-86E5-4034-AA0B-F469E441F9C5}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{C9D85F7A-86E5-4034-AA0B-F469E441F9C5}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{C9D85F7A-86E5-4034-AA0B-F469E441F9C5}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{C9D85F7A-86E5-4034-AA0B-F469E441F9C5}.Release|Any CPU.Build.0 = Release|Any CPU
+		{D965940D-E758-4A7C-977A-74E5793C593B}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{D965940D-E758-4A7C-977A-74E5793C593B}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{D965940D-E758-4A7C-977A-74E5793C593B}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{D965940D-E758-4A7C-977A-74E5793C593B}.Release|Any CPU.Build.0 = Release|Any CPU
+		{21CE6A7D-CC82-4F41-A28F-54D2E535FB3F}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
+		{21CE6A7D-CC82-4F41-A28F-54D2E535FB3F}.Debug|Any CPU.Build.0 = Debug|Any CPU
+		{21CE6A7D-CC82-4F41-A28F-54D2E535FB3F}.Release|Any CPU.ActiveCfg = Release|Any CPU
+		{21CE6A7D-CC82-4F41-A28F-54D2E535FB3F}.Release|Any CPU.Build.0 = Release|Any CPU
+	EndGlobalSection
+	GlobalSection(SolutionProperties) = preSolution
+		HideSolutionNode = FALSE
+	EndGlobalSection
+	GlobalSection(ExtensibilityGlobals) = postSolution
+		SolutionGuid = {972D1D6C-AC89-49B8-9AE0-EB671A0842D5}
+	EndGlobalSection
+EndGlobal

C#入门/Lession1练习题/Lesson1练习题.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

C#入门/Lession1练习题/Program.cs

@@ -0,0 +1,17 @@
+using System;
+
+namespace 练习题
+{
+    class program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine("*************");
+            for (int i = 0; i < 10; i++)
+            {
+                Console.WriteLine("*           *");
+            }
+            Console.WriteLine("*************");
+        }
+    }
+}

C#入门/Lesson2变量/Lesson2变量.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

C#入门/Lesson2变量/Program.cs

@@ -0,0 +1,2 @@
+// See https://aka.ms/new-console-template for more information
+Console.WriteLine("Hello, World!");

C#入门/lesson1/Lesson1注释&输入输出.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>

C#入门/lesson1/Program.cs

@@ -0,0 +1,40 @@
+//双杠注释
+using System;
+
+namespace Lession1
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine("Hello world");
+            //writeline是输出后换行
+            Console.WriteLine("你好");
+            //wirte是输出后不换行
+            Console.Write("请输入一些东西：");
+            //这是输入一行东西，不按回车不算结束
+            Console.ReadLine();
+            Console.WriteLine("输入完成");
+            Console.Write("请输入一些东西：");
+            //检测用户是否按键，只要按了任意一个按键就算结束
+            Console.ReadKey();
+            Console.WriteLine("输入完成");
+        }
+    }
+}
+
+/*多杠注释
+ * 
+ * 
+ */
+
+
+///三杠注释
+///</summary>
+///类
+///</summary>
+//Console.WriteLine("你好!");
+
+
+//Ctrl + K + U取消注释
+//Ctrl + K + C注释快捷键 

C#入门/test1/Program.cs

@@ -0,0 +1,13 @@
+using System;
+
+namespace 测试项目
+{
+    class Program
+    {
+        static void Main(string[] args)
+        {
+            Console.WriteLine("hello world");
+        }
+    }
+}
+   

C#入门/test1/test1.csproj

@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net8.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>