>>29の一部だけ。あとはGUIでD&D対応すればいいだけ。

using System.Diagnostics;
using System.IO;
using System.Text;
using System.Web.UI;

class Test
{
  public static void Main() {

    // CSVの読み込み
    string csv_text = null;
    using ( TextReader r = File.OpenText("data.csv") ) {
      csv_text = r.ReadToEnd();
    }

    // HTMLの書き込み
    using ( TextWriter w = new StreamWriter("table.html", false, Encoding.Default) ) {
      HtmlTextWriter w2 = new HtmlTextWriter(w, " ");

      w2.WriteFullBeginTag("html");
      w2.WriteLine();

      w2.Indent++;
      w2.WriteFullBeginTag("body");
      w2.WriteLine();

      w2.Indent++;
      w2.WriteBeginTag("table");
      w2.WriteAttribute("border", "1");
      w2.Write(HtmlTextWriter.TagRightChar);
      w2.WriteLine();