学步园

http://hi.baidu.com/ivanbobo/blog/item/63571d1744ea941bc83d6ddd.html

public partial class MDI : Form
    {   
        public delegate void PostText(string text);
        public event PostText PT;
        public MDI()
        {
            InitializeComponent();
        }

        private void MDI_Activated(object sender, EventArgs e)
        {
            MDIParent1 mdiForm = (MDIParent1)this.MdiParent;
            
            mdiForm.GetText(this.Text);//往往父窗体控件都为私有的，委托的
           
           
        }

    }

在MDIParent1中代码：

 public partial class MDIParent1 : Form
    {
        private int childFormNumber = 0;

        public MDIParent1()
        {
            InitializeComponent();
        }

        private void ShowNewForm(object sender, EventArgs e)
        {
            // 创建此子窗体的一个新实例。
            MDIApplication.MDI childForm = new MDIApplication.MDI();
            // 在显示该窗体前使其成为此 MDI 窗体的子窗体。
            childForm.MdiParent = this;
            childForm.WindowState = FormWindowState.Maximized;
            childForm.Text = "窗口" + childFormNumber++;
            childForm.Show();

            childForm.PT += new MDI.PostText(GetText);
            
        }

        public void GetText(string text)
        {
            this.statusStrip.Items[0].Text = text;
        }
    }
}