C#

object value = reg.GetValue("SomeName");
if (value is string)
{
}
else if (value.GetType() == typeof(int))
{
}
else if (value.GetType() == typeof(long))
{
}
else if (value is Array)
{
}
else throw new InvalidOperationException("Unknown registry key type.");

// str is string
ldloc.0 // location of str in local variable stack
isinst [mscorlib]System.String
 
// str.GetType() == typeof(string)
ldloc.0
callvirt instance class [mscorlib]System.Type [mscorlib]System.Object::GetType()
ldtoken [mscorlib]System.String
call class [mscorlib]System.Type [mscorlib]System.Type::GetTypeFromHandle(
  valuetype [mscorlib]System.RuntimeHandle)

using System;
using System.Drawing;
using System.Windows.Forms;

public class Test : Form
{
  static void Main()
  {
    Test t = new Test();
    t.ShowDialog();
    Application.Run();
  }

  TextBox tb;
  public Test()
  {
    tb = new TextBox();
    tb.Location = new Point(8, 8);
    Controls.Add(tb);

    Button b = new Button();
    b.Location = new Point(tb.Right + 8, tb.Top);
    b.Text = "Click";
    b.Click += new EventHandler(b_Click);
    Controls.Add(b);
  }

  private void b_Click(object sender, EventArgs e)
  {
    MessageBox.Show(tb.Text);
    Application.Exit();
  }
}