Category Archives: .NET

Announcing WinUI 3 Preview 2

At our monthly community call this morning we announced that a new preview of WinUI 3 is ready for you all to try out – WinUI 3 Preview 2! If you’re too excited to read ahead, check out the release notes here. WinUI 3 Preview 2 was a quality and stability-driven release. It builds directly […]

情報源: Announcing WinUI 3 Preview 2 – Windows Developer Blog


A deep-dive into WinUI 3 in desktop apps – Windows Developer Blog

XAML Islands was our first solution to enable developers to use UWP XAML inside their desktop (Win32) apps. Within a couple of months after the release of XAML Islands, behavioral insights and customer interviews raised some signals about how developers were using it. We discovered that a significant number of apps were using XAML for […]

情報源: A deep-dive into WinUI 3 in desktop apps – Windows Developer Blog



情報源: Excel spreadsheet library for .NET Framework/Core – EPPlus Software


C#: Code DomainでRoslynコンパイラを使用する


GitHub – aspnet/RoslynCodeDomProvider: Roslyn CodeDOM provider

NuGet packages · dotnet/roslyn Wiki · GitHub(RoslynのバージョンとC#バージョンとの対応)

C# コンパイラを使用してプログラムによってコードをコンパイルする方法

上のサンプルをRoslyn CodeDom providerを使用するように変更した。

using System;
using System.Drawing;
using System.Windows.Forms;
using System.CodeDom.Compiler;
using System.Diagnostics;

namespace CodeDomainSample
    public partial class Form1 : Form
        public Form1()

        private void button1_Click(object sender, System.EventArgs e)
            CodeDomProvider codeProvider = new Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider();
            string Output = "Out.exe";
            Button ButtonObject = (Button)sender;

            textBox2.Text = "";
            System.CodeDom.Compiler.CompilerParameters parameters = new CompilerParameters();
            //Make sure we generate an EXE, not a DLL
            parameters.GenerateExecutable = true;
            parameters.OutputAssembly = Output;
            parameters.CompilerOptions = "-langversion:7.3"; // C#のバージョンを指定する。
            CompilerResults results = codeProvider.CompileAssemblyFromSource(parameters, textBox1.Text);

            if (results.Errors.Count > 0)
                textBox2.ForeColor = Color.Red;
                foreach (CompilerError CompErr in results.Errors)
                    textBox2.Text = textBox2.Text +
                                "Line number " + CompErr.Line +
                                ", Error Number: " + CompErr.ErrorNumber +
                                ", '" + CompErr.ErrorText + ";" +
                                Environment.NewLine + Environment.NewLine;
                //Successful Compile
                textBox2.ForeColor = Color.Blue;
                textBox2.Text = "Success!";
                //If we clicked run then launch our EXE
                if (ButtonObject.Text == "Run") Process.Start(Output);

        private void button2_Click(object sender, EventArgs e)
            button1_Click(sender, e);


Nullable Reference Types: Contexts and Attributes – A Look at New Language Features in C# 8 – .NET Tools Blog.NET Tools Blog

Our C# 8 language features series is coming to an end. Before we jump into nullable contexts and nullable attributes, here is a quick (updated) recap of our roadmap: Indices, Ranges, and Null-coalescing Assignments Switch Expressions and Pattern-Based Usings Recursive … Continue reading →

情報源: Nullable Reference Types: Contexts and Attributes – A Look at New Language Features in C# 8 – .NET Tools Blog.NET Tools Blog


Nullable Reference TypesはC#8.0で追加されました。これは将来のC#でのNull全面不許可への第一歩です。Nullable Reference TypesはNull全面不許可における例外を設けるために作られたものです。なので、古いクラスライブラリなどどうしようも無い部分はあるのですが、C#erは極力Nullを避けるコーディング習慣を身につけるように努力した方が良いと思います。

build 2020 – The Journey to One .NET

Join us for the Microsoft Build 48-hour, digital event to expand your skillset, find technical solutions, and innovate for the challenges of tomorrow.

情報源: MyBuild – The Journey to One .NET