using System; 
  using System.Collections.Generic; 
  using System.ComponentModel; 
  using System.Data; 
  using System.Drawing; 
  using System.Linq; 
  using System.Text; 
  using System.Windows.Forms; 
   
  namespace WindowsFormsApplication1 
  { 
      public partial class Form1 : Form 
      { 
   
          public Form2 frm2; 
          public Form1() 
          { 
              InitializeComponent(); 
              frm2 = new Form2(); 
              frm2.frm1 = this; 
          } 
   
          private void btnGiris_Click(object sender, EventArgs e) 
          { 
              frm2.ShowDialog(); 
              frm2.radioGiris.Checked = true; 
          } 
   
          private void btnCikis_Click(object sender, EventArgs e) 
          { 
              frm2.ShowDialog(); 
              frm2.radioCikis.Checked = true; 
          } 
   
   
   
   
        
      } 
  } 
  

using System; 
  using System.Collections.Generic; 
  using System.ComponentModel; 
  using System.Data; 
  using System.Drawing; 
  using System.Linq; 
  using System.Text; 
  using System.Windows.Forms; 
   
  namespace WindowsFormsApplication1 
  { 
      public partial class Form2 : Form 
      { 
          public Form1 frm1;  
          public Form2() 
          { 
              InitializeComponent(); 
   
          } 
   
   
          private void radioButton1_CheckedChanged(object sender, EventArgs e) 
          { 
              label1.Text = "Firma"; 
              label2.Text = "Giriş Yapan";        
          } 
   
          private void radioButton2_CheckedChanged(object sender, EventArgs e) 
          { 
              label1.Text = "Bayi"; 
              label2.Text = "Çıkış Yapan"; 
          } 
   
          private void btnKapat_Click(object sender, EventArgs e) 
          { 
              this.Close(); 
          } 
          
           
      } 
  }