Exsharp - see http://var.blog.jp/archives/75948600.html

Actions.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace Exsharp
{
    public class Actions : Dictionary<string, Func<object, object>>
    {
        public new Func<object, object> this[string key]
        {
            get
            {
                if (this.ContainsKey(key))
                {
                    return base[key];
                }
                else
                {
                    return null;
                }
            }
            set
            {
                base[key] = value;
            }
        }
    }
}

App.config

<?xml version="1.0" encoding="utf-8"?>
<configuration>
    <startup> 
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.6" />
    </startup>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="System.Collections.Immutable" publicKeyToken="b03f5f7f11d50a3a" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-1.2.1.0" newVersion="1.2.1.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.IO.Compression" publicKeyToken="b77a5c561934e089" culture="neutral" />
        <bindingRedirect oldVersion="0.0.0.0-4.1.2.0" newVersion="4.1.2.0" />
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      <dependentAssembly>
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      <dependentAssembly>
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      </dependentAssembly>
      <dependentAssembly>
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        <bindingRedirect oldVersion="0.0.0.0-4.0.3.0" newVersion="4.0.3.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
</configuration>

App.xaml

<Application x:Class="Exsharp.App"
             xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
             xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
             xmlns:local="clr-namespace:Exsharp"
             StartupUri="MainWindow.xaml">
    <Application.Resources>
         
    </Application.Resources>
</Application>

App.xaml.cs

using System;
using System.Collections.Generic;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Threading.Tasks;
using System.Windows;

namespace Exsharp
{
    /// <summary>
    /// App.xaml の相互作用ロジック
    /// </summary>
    public partial class App : Application
    {
    }
}

DelegateCommand.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Input;

namespace Exsharp
{
    public class DelegateCommand : ICommand
    {
        private Action<object> execute { get; }
        private Func<object, bool> canExecute { get; }

        public event EventHandler CanExecuteChanged
        {
            add { CommandManager.RequerySuggested += value; }
            remove { CommandManager.RequerySuggested -= value; }
        }

        public DelegateCommand(Action<object> execute, Func<object, bool> canExecute = null)
        {
            this.execute = execute;
            this.canExecute = canExecute;
        }

        public DelegateCommand(Action execute, Func<bool> canExecute = null)
        {
            this.execute = _ => execute();
            this.canExecute = canExecute != null ? _ => canExecute() : (Func<object,bool>)null;
        }

        public void Execute(object parameter = null)
        {
            this.execute(parameter);
        }

        public bool CanExecute(object parameter = null)
        {
            return this.canExecute?.Invoke(parameter) ?? true;
        }
    }
}

Exsharp.csproj

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="14.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <Import Project="$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props" Condition="Exists('$(MSBuildExtensionsPath)\$(MSBuildToolsVersion)\Microsoft.Common.props')" />
  <PropertyGroup>
    <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
    <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
    <ProjectGuid>{EF22406A-5152-4EB8-9920-2428C8234E8E}</ProjectGuid>
    <OutputType>WinExe</OutputType>
    <AppDesignerFolder>Properties</AppDesignerFolder>
    <RootNamespace>Exsharp</RootNamespace>
    <AssemblyName>Exsharp</AssemblyName>
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    <PlatformTarget>AnyCPU</PlatformTarget>
    <DebugSymbols>true</DebugSymbols>
    <DebugType>full</DebugType>
    <Optimize>false</Optimize>
    <OutputPath>bin\Debug\</OutputPath>
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       Other similar extension points exist, see Microsoft.Common.targets.
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Exsharp.sln

Microsoft Visual Studio Solution File, Format Version 12.00
# Visual Studio Express 14 for Windows Desktop
VisualStudioVersion = 14.0.25420.1
MinimumVisualStudioVersion = 10.0.40219.1
Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Exsharp", "Exsharp.csproj", "{EF22406A-5152-4EB8-9920-2428C8234E8E}"
EndProject
Global
	GlobalSection(SolutionConfigurationPlatforms) = preSolution
		Debug|Any CPU = Debug|Any CPU
		Release|Any CPU = Release|Any CPU
	EndGlobalSection
	GlobalSection(ProjectConfigurationPlatforms) = postSolution
		{EF22406A-5152-4EB8-9920-2428C8234E8E}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
		{EF22406A-5152-4EB8-9920-2428C8234E8E}.Debug|Any CPU.Build.0 = Debug|Any CPU
		{EF22406A-5152-4EB8-9920-2428C8234E8E}.Release|Any CPU.ActiveCfg = Release|Any CPU
		{EF22406A-5152-4EB8-9920-2428C8234E8E}.Release|Any CPU.Build.0 = Release|Any CPU
	EndGlobalSection
	GlobalSection(SolutionProperties) = preSolution
		HideSolutionNode = FALSE
	EndGlobalSection
EndGlobal

Exsharp.zip

MainWindow.xaml

<Window x:Class="Exsharp.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
        xmlns:d="http://schemas.microsoft.com/expression/blend/2008"
        xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006"
        xmlns:local="clr-namespace:Exsharp"
        mc:Ignorable="d"
        Title="Exsharp" Height="600" Width="800">
    <Grid>
        <TabControl>
            <TabItem Header="エクセル" Padding="10 5" MinWidth="90">
                <Grid>
                    <Grid.RowDefinitions>
                        <RowDefinition Height="Auto"/>
                        <RowDefinition Height="1*"/>
                        <RowDefinition Height="Auto"/>
                        <RowDefinition Height="1*"/>
                    </Grid.RowDefinitions>

                    <Border Grid.Row="0" BorderBrush="#999" BorderThickness="0 0 0 1">
                        <Grid>
                            <StackPanel Orientation="Horizontal" Margin="3">
                                <Button Width="30" Height="30" Background="#f0f0f0" Margin="5 0" Command="{Binding run_command}">▶</Button>
                                <Button Width="30" Height="30" Background="#f0f0f0" Margin="5 0" Command="{Binding open_command}">📖</Button>
                            </StackPanel>
                            <StackPanel Orientation="Horizontal" Margin="3" HorizontalAlignment="Right">
                                <Button Width="30" Height="30" Background="#f0f0f0" Margin="5 0" Command="{Binding historyPrev_command}">⇧</Button>
                                <Button Width="30" Height="30" Background="#f0f0f0" Margin="5 0" Command="{Binding historyNext_command}">⇩</Button>
                            </StackPanel>
                        </Grid>
                    </Border>

                    <TextBox Grid.Row="1" Text="{Binding source,UpdateSourceTrigger=PropertyChanged}" FontFamily="monaco,meiryoke_console,consolas" Margin="3 8 3 5" TextWrapping="Wrap" AcceptsReturn="True" BorderThickness="1">
                        <TextBox.InputBindings>
                            <KeyBinding Modifiers="Ctrl" Key="Enter" Command="{Binding run_command}" />
                            <KeyBinding Modifiers="Alt" Key="Up" Command="{Binding historyPrev_command}" />
                            <KeyBinding Modifiers="Alt" Key="Down" Command="{Binding historyNext_command}" />
                        </TextBox.InputBindings>
                    </TextBox>
                    <GridSplitter Grid.Row="2" Background="#ccc" Height="2" HorizontalAlignment="Stretch"/>
                    <TextBox Grid.Row="3" Text="{Binding result}" FontFamily="monaco,meiryoke_console,consolas" Margin="3 5 3 8" TextWrapping="Wrap" AcceptsReturn="True" BorderThickness="1" IsReadOnly="True"/>
                </Grid>
            </TabItem>
            <TabItem Header="ログ" Padding="10 5" MinWidth="90">
                <ScrollViewer Background="#fffef5" HorizontalScrollBarVisibility="Visible" VerticalScrollBarVisibility="Visible">
                    <Grid>
                        <TextBox Text="{Binding log}" IsReadOnly="True" Background="Transparent" BorderThickness="0"/>
                    </Grid>
                </ScrollViewer>
            </TabItem>
        </TabControl>
    </Grid>
</Window>

MainWindow.xaml.cs

using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Data;
using System.Windows.Documents;
using System.Windows.Input;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using System.Windows.Navigation;
using System.Windows.Shapes;
using Microsoft.Win32;

namespace Exsharp
{
    /// <summary>
    /// MainWindow.xaml の相互作用ロジック
    /// </summary>
    public partial class MainWindow : Window
    {
        private Actions actions { get; }

        public MainWindow()
        {
            InitializeComponent();

            var actions = this.createVActions();
            this.actions = actions;
            var vm = new ViewModel { actions = actions };
            this.DataContext = vm;

            this.Closing += (sender, e) =>
            {
                this.actions["windowClosing"]?.Invoke(null);
            };
        }

        private Actions createVActions()
        {
            return new Actions
            {
                ["openFile"] = _ =>
                {
                    var ofd = new OpenFileDialog();

                    ofd.Filter = "Excelファイル(*.xlsx;*.xls)|*.xlsx;*.xls";
                    ofd.Title = "開くファイルを選択してください";
                    ofd.RestoreDirectory = true;

                    if (ofd.ShowDialog() == true && File.Exists(ofd.FileName))
                    {
                        return ofd.FileName;
                    }
                    return null;
                },
            };
        }
    }
}

packages.config

Release.zip

Scripting.cs

ViewModel.cs

ViewModelBase.cs