1.frmmain.cs部分：
private string m_strConfigFile;
        private DeserializeDockContent m_deserializeDockContent;
        public frmMain()
        {
            InitializeComponent();
            InitializeLeftBar();
        }
        private void InitializeLeftBar()
        {
            m_deserializeDockContent = new DeserializeDockContent(GetContentFromPersistString);
            frmTemp = this;
            m_strConfigFile = Path.Combine(Path.GetDirectoryName(Application.ExecutablePath), "DockPanel.config");
            m_deserializeDockContent = new DeserializeDockContent(GetContentFromPersistString);
        }
        private IDockContent GetContentFromPersistString(string persistString)
        {
            if (persistString == typeof(frmLeftBar).ToString())
            {
                return frmLeftBar;
            }
            else
            {
                // 可以加的其它子窗体
                return null;
            }
        }

2.加载主窗口
private void frmMain_Load(object sender, EventArgs e)
        {
            globalcolor = System.Drawing.Color.FromArgb(Convert.ToInt32(W1.LoadXmlFileValue("config.xml", "Color", "UserColor")));
            globalcolor2 = System.Drawing.Color.FromArgb(Convert.ToInt32(W1.LoadXmlFileValue("config.xml", "Color", "IMColor")));
            CreditControl = Convert.ToBoolean(C_BaseInfo.GetsysConf().Tables[0].Rows[0]["CreditControl"]);
            //设置时间和日期
            tssl1.Text = "今天日期：" + DateTime.Now.ToString("yyyy-MM-dd");
            tssl2.Text = "登录时间：" + System.DateTime.Now.ToLongTimeString();
            tsslLoginUser.Text = "当前用户：" + " " + frmLogin.C_UserInfo.SysUser;
            MenuStrip ms = (MenuStrip)this.Controls["menuStrip1"];
            ArrayList arr = new ArrayList();
            dsright = C_BaseInfo.UserRight(frmLogin.C_UserInfo);
            GetMenuAllName(arr, null, 0, ms);//调用递归函数
            if (File.Exists(m_strConfigFile))
            {
                dockPanel1.LoadFromXml(m_strConfigFile, m_deserializeDockContent);
            }
            frmLeftBar.Show(this.dockPanel1, DockState.DockLeft);
            this.dockPanel1.BackgroundImage = global::ECM.Properties.Resources.cable_16_92;




        }
3.显示子窗口
private ECM.Purchase.frmPO frmpo = null;
        private void mnuPO_Click(object sender, EventArgs e)
        {
            if (FindFormName("frmPO") == null)
            {
                frmpo = new ECM.Purchase.frmPO(this);

            
            frmpo.MdiParent = this;
            frmpo.Show(frmMain.frmTemp.dockPanel1);
            frmpo.Focus();
            }
            else
            {
                Form f = FindFormName("frmPO") as Form;
                f.Focus();
            }

        }