text-input-all-2.ps1

$code = @"
using System;
using System.IO;
using System.Text;
using System.Windows.Forms;
 
public class Program
{
    [STAThread]
    public static void Main()
    {
 
        OpenFileDialog openFileDialog = new OpenFileDialog();
        openFileDialog.Filter = "テキスト|*.txt|全て|*.*";
        openFileDialog.FilterIndex = 2;
        openFileDialog.InitialDirectory = @"C:\";
 
        if (openFileDialog.ShowDialog() != DialogResult.OK)
        {
            return;
        }
 
        Console.WriteLine(openFileDialog.FileName);
 
        string path = openFileDialog.FileName;
        if ( File.Exists(path) )
        {
            Console.WriteLine("{0} は存在しています", path );
        }
 
        // SHIFT_JIS
        Encoding Enc = Encoding.GetEncoding(932);
 
        try
        {
            using (StreamReader ReadFile = new StreamReader(path, Enc))
            {
                // 読込み
                string Text = ReadFile.ReadToEnd();
 
                // 全て読み込んでいるので閉じる
                ReadFile.Close();
 
                Console.WriteLine(Text);
            }
 
        }
        catch (Exception ex)
        {
            Console.WriteLine(ex.Message);
        }
 
        Console.ReadLine();
    }
}
"@
 
Add-Type -Language CSharp -TypeDefinition $code -ReferencedAssemblies ("System.Windows.Forms")
  
[Program]::Main()