2012-11-12 36 views
1

我想从数据库创建一个菜单并在菜单控制中显示。如何使用asp.net中的菜单控件从数据库创建动态菜单?

代码这里在.aspx页面中:

<asp:Menu ID="Menu1" Orientation="horizontal" StaticMenuItemStyle-CssClass="menuItem" 
          DynamicMenuItemStyle-CssClass="menuItem" runat="server"> 

在法师的.cs页:

protected void Page_Load(object sender, EventArgs e) 
    { 
     if (!IsPostBack) 
     { 

      populateMenuItem(); 
     } 

    } 

    private void populateMenuItem() 
    { 

     DataTable menuData = GetMenuData(); 
     AddTopMenuItems(menuData); 

    } 
    /// Filter the data to get only the rows that have a 
    /// null ParentID (This will come on the top-level menu items) 

    private void AddTopMenuItems(DataTable menuData) 
    { 
     DataView view = new DataView(menuData); 
     view.RowFilter = "DepartmentParentID IS NULL"; 
     foreach (DataRowView row in view) 
     { 
      //MenuItem newMenuItem = new MenuItem(row["DepartmentName"].ToString(), row["DepartmentID"].ToString()); 
      MenuItem newMenuItem = new MenuItem(row["DepartmentName"].ToString(), row["DepartmentID"].ToString()); 

      Menu1.Items.Add(newMenuItem); 
      AddChildMenuItems(menuData, newMenuItem); 
     } 

    } 
    //This code is used to recursively add child menu items by filtering by ParentID 

    private void AddChildMenuItems(DataTable menuData, MenuItem parentMenuItem) 
    { 
     DataView view = new DataView(menuData); 
     view.RowFilter = "DepartmentParentID=" + parentMenuItem.Value; 
     foreach (DataRowView row in view) 
     { 
      MenuItem newMenuItem = new MenuItem(row["DepartmentName"].ToString(), row["DepartmentID"].ToString()); 
      parentMenuItem.ChildItems.Add(newMenuItem); 
      AddChildMenuItems(menuData, newMenuItem); 
     } 
    } 


    private DataTable GetMenuData() 
    { 
     using (SqlConnection con = new SqlConnection(conStr)) 
     { 

      using (SqlCommand cmd = new SqlCommand("SELECT DepartmentID,OfficeID,DepartmentName,DepartmentParentID,IsActive,CreatedByID,CreatedDate,LastModifiedByID,LastModifiedDt FROM DepartmentMst", con)) 
      { 
       SqlDataAdapter da = new SqlDataAdapter(cmd); 
       DataTable dt = new DataTable(); 
       da.Fill(dt); 
       return dt; 
      } 

     } 
    } 

问题是在AddTopMenuItems()方法,其中显示“未将对象引用设置为实例的对象“在行Menu1.Items.Add(newMenuItem); 不知道为什么?

下面是数据在SQLSERVER2008 DepartmentMst:

DepartmentID DepartmentName IsActive DepartmentParentID 
1    HR   1   NULL 
2    IT   1   NULL 
3   Operations 1    NULL 
4   Desktop Engineer 1    2 
5   Network Engineer 1    2 
6   Employee Salary 1    1 

当DepartmentParentID为NULL,则它是主菜单,如果不是null,则它与尊重其父ID子节点。

样品这里http://chandradev819.wordpress.com/2011/07/03/how-to-bind-asp-net-menu-control-with-database/

帮助感激!

回答

4

我怀疑你放在里面菜单控制母版页的内容占位符:

​​

ContentPlaceHolder控件是用来定义母版页可以取代的区域与来自与母版页关联的另一页面的内容(显示子页面)。

由于菜单将所有页面从母版页继承只需移动菜单随时随地内容占位符之间的共享控制,你会好起来:

<asp:Menu ID="Menu1" Orientation="horizontal" StaticMenuItemStyle-CssClass="menuItem" 
    DynamicMenuItemStyle-CssClass="menuItem" runat="server" /> 
<asp:ContentPlaceHolder ID="ContentPlaceHolder1" runat="server"> 
</asp:ContentPlaceHolder> 
+0

感谢@ Deni ...现在我知道了...... :) –

+0

Plz告诉我如何从Master页面获取Content Page中的Selected MenuItem。例如:如果Department是“DesktopEngineer”,那么我需要它存储在数据库中的相应值? –

+0

看看这篇文章 - http://stackoverflow.com/questions/2770042/set-item-selected-in-asp-net-menu-control –