C#ソース-Windowsフォームにフォームコントロール、btnOKボタンのClickイベントを追加

using System;
using System.Windows.Forms;
namespace TestInterface
{
    public partial class TestInterface : Form //  TestInterface 
    {
        interface IStudent    //    IStudent
        {
            string Answer();
        }
        class Student : IStudent  //   Student，     IStudent    Answer  
        {
            public int no;
            public string name;
            public string Answer()
            {
                string result = "       ：";
                result += "
  ：" + no;
                result += "
  ：" + name;
                return result;
            }
        }
private void btnOk_Click(object sender, EventArgs e)
//  btnOK   Click  
        {
            Student a = new Student();    
            // Student     a，    
            a.no = Convert.ToInt32(txtStuID.Text);
            a.name = txtName.Text;
            lblShow.Text = a.Answer();
        }
    }
}