C#에서 두 Form 간에 값을 전달하는 방법

 //Form1   ：
   public Form1()
        {
            InitializeComponent();
        }
   private void button1_Click(object sender, EventArgs e)
        {
            Form2 lForm = new Form2();//     Form2  
            lForm.String1 = "      Form2  ";//  Form2 string1  
            lForm.SetValue();//  Form2 Label1 
            lForm.ShowDialog();
        }

 //Form2   ：

  private string string1;
  public string String1
     {
       set
          {
               string1 = value;
          }
     }
    public void SetValue()
        {
            this.label1.Text = string1;
        }
    public Form2()
        {
            InitializeComponent();
        }

//Form1   ：
  public Form1()
     {
        InitializeComponent();
     }
  private string strValue;
  public string StrValue
    {
       set
         {
            strValue = value;
         }
    }
  private void btnShowForm2_Click(object sender, EventArgs e)
    {
         Form2 lForm = new Form2();
         lForm.Owner = this;//     ，    Form2 Owner    Form1
         lForm.ShowDialog();
         MessageBox.Show(strValue);//      
    }

 //From2   ：
 public Form2()
   {
       InitializeComponent();
   }
 private void btnClose_Click(object sender, EventArgs e)
   {
       Form1 lForm1 = (Form1)this.Owner;// Form2        lForm1
       lForm1.StrValue = "   Form2      ";//         
       this.Close();
   }