C# MDI问题

Question

Form1:    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }        private void button1_Click(object sender, EventArgs e)
        {
            Form2 f2 = new Form2(this);
            f2.MdiParent = this;
            f2.Show();
        }
    }
Form2:  public partial class Form2 : Form
    {        public Form1 form1 = null;         public Form2()
        {
            InitializeComponent();
        }        public Form2(Form1 f1)
        {
            this.form1 = f1;
            InitializeComponent();
        }        private void button1_Click(object sender, EventArgs e)
        {
            Form2_2 f22 = new Form2_2(form1);
            f22.Show();
        }
    }
Form2-2:public partial class Form2_2 : Form
    {        public Form2_2()
        {
            InitializeComponent();
        }        public Form2_2(Form1 f1)
        {
            this.MdiParent = f1;
            InitializeComponent();
        }
    }

Answer 1

在你Form2调用 Form2_2时//Form2
    //'this' is Form2
    f2_2.MdiParent = this.MdiParent;