????1??????????壺
???????????????????????????壬??軔??????IsMdiContainer?????????True???ɡ?

????2??????????壺
??????????????????MdiParent????????????????????????????塣
?????????£?
????1: public Form MdiParent{get;set;}
????3??????MDI????壺
??????????:
????1: public void LayoutMdi(MdiLayout value)
????value:??MdiLayout??????????????????MDI??????????

????????;

1: public partial class FormMain : Form
2:     {
3:         public FormMain()
4:         {
5:             InitializeComponent();
6:         }
7:
8:         private void ?????????ToolStripMenuItem_Click(object sender?? EventArgs e)
9:         {
10:             FormChild_1 frm1 = new FormChild_1();
11:             frm1.MdiParent = this;
12:             frm1.Show();
13:
14:             FormChild_2 frm2 = new FormChild_2();
15:             frm2.MdiParent = this;
16:             frm2.Show();
17:
18:             FormChild_3 frm3 = new FormChild_3();
19:             frm3.MdiParent = this;
20:             frm3.Show();
21:         }
22:
23:         private void ?????ToolStripMenuItem_Click(object sender?? EventArgs e)
24:         {
25:             LayoutMdi(MdiLayout.TileHorizontal);
26:         }
27:
28:         private void ??????ToolStripMenuItem_Click(object sender?? EventArgs e)
29:         {
30:             LayoutMdi(MdiLayout.TileVertical);
31:         }
32:
33:         private void ???????ToolStripMenuItem_Click(object sender?? EventArgs e)
34:         {
35:             LayoutMdi(MdiLayout.Cascade);
36:         }
37:
38:     }