來開始嘗試第一支 .NET Core Console 程式吧！
這裡會在 Windows 環境下使用 dotnet 來執行 Console 程式，並顯示出 Hello Word!
先打開命令提示字元，用 dotnet 指令，
1.建立一個資料夾叫做 1_HelloWorld
mkdir 1_HelloWorld
2.切換到該目錄中
cd 1_helloworld
3.在這目錄裡面建立新專案
dotnet new
會看到 Program.cs
using System;
class Program
{
static void Main(string[] args)
{
Console.WriteLine("Hello World!");
}
}
與 project.json
{
"version": "1.0.0-*",
"buildOptions": {
"debugType": "portable",
"emitEntryPoint": true
},
"dependencies": {},
"frameworks": {
"netcoreapp1.0": {
"dependencies": {
"Microsoft.NETCore.App": {
"type": "platform",
"version": "1.0.0"
}
},
"imports": "dnxcore50"
}
}
}
4. 第一次要還原必要套件
dotnet restore
執行後會多了 project.lock.json，以下列出部分內容
{
"locked": false,
"version": 2,
"targets": {
".NETCoreApp,Version=v1.0": {
"Libuv/1.9.0": {
"type": "package",
"dependencies": {
"Microsoft.NETCore.Platforms": "1.0.1"
},
"runtimeTargets": {
"runtimes/osx/native/_._": {
"assetType": "native",
"rid": "osx"
}
}
},
"Microsoft.CodeAnalysis.Analyzers/1.1.0": {
"type": "package"
},
5.編譯且執行程式
dotnet run
會看到編譯結果
Project 1_HelloWorld (.NETCoreApp,Version=v1.0) will be compiled because expected outputs are missing
Compiling 1_HelloWorld for .NETCoreApp,Version=v1.0
Compilation succeeded.
0 Warning(s)
0 Error(s)
Time elapsed 00:00:01.5697792
還有執行結果
Hello World!
專案編譯後的 DLL 會放在
1_HelloWorld\bin\Debug\netcoreapp1.0\1_HelloWorld.dll
6. 接著我們直接執行 1_HelloWorld.dll 試試，這次不是使用 dotnet run ，而是直接切換到 netcoreapp1.0 目錄下
cd bin\Debug\netcoreapp1.0
然後直接用 dotnet 執行程式
dotnet 1_helloworld.dll
就能看到命令提示字元上顯示
Hello World!
7. 如果你不想用 dotnet 指令來執行呢? 我在 Windows 平台，當然是要 exe 才爽阿，
那我們接著就到 project.json 的 frameworks 加上需要的目標 framework(參考這篇 Project.json definition dnx451 vs .dotnet ( 4.51)，
我這邊就加上 dnx46(我電腦有安裝 .Net Framework 4.6 SDK )，
{
"version": "1.0.0-*",
"buildOptions": {
"debugType": "portable",
"emitEntryPoint": true
},
"dependencies": {},
"frameworks": {
"dnx46":{},
"netcoreapp1.0": {
"dependencies": {
"Microsoft.NETCore.App": {
"type": "platform",
"version": "1.0.0"
}
},
"imports": "dnxcore50"
}
}
}
8. 然後在 \1_HelloWorld\ 這裡下指令發行專案，就會將各個 frameworks 發行出來為各平台目標的檔案，
dotnet publish
輸出訊息
d:\1_HelloWorld>dotnet publish
Publishing 1_HelloWorld for .NETCoreApp,Version=v1.0
Project 1_HelloWorld (.NETCoreApp,Version=v1.0) will be compiled because inputs were modified
Compiling 1_HelloWorld for .NETCoreApp,Version=v1.0
Compilation succeeded.
0 Warning(s)
0 Error(s)
Time elapsed 00:00:00.9054530
publish: Published to d:\1_HelloWorld\bin\Debug\netcoreapp1.0\publish
Publishing 1_HelloWorld for DNX,Version=v4.6/win7-x64
Project 1_HelloWorld (DNX,Version=v4.6) will be compiled because Input items added from last build
Compiling 1_HelloWorld for DNX,Version=v4.6
Compilation succeeded.
0 Warning(s)
0 Error(s)
Time elapsed 00:00:00.8461498
publish: Published to d:\1_HelloWorld\bin\Debug\dnx46\win7-x64\publish
Published 2/2 projects successfully
你應該會看到在 1_HelloWorld\bin\Debug\ 下多了 dnx46 目錄，裡面就有你熟悉的 1_HelloWorld.exe，
在用命令提示字元直接執行看看
\1_HelloWorld\bin\Debug\dnx46>1_helloworld
輸出結果
Hello World!
Hello World 第一步踏出來了!
參考文章