删除其他下拉列表中的选定条目

Question

我有2 DropDownList s具有相同的内容（即金融，市场营销，促销）。我想从列表的其余部分删除已选定的值。

示例：如果我为第一个列表选择“finance”，则应该在其他列表中删除它;第二个列表应该只显示“营销”和“促销”。

但是，当第一个值选择任何值时，当前的代码仍然在其他列表中显示所有值。

ASP.NET页面

<asp:DataList ID="dldepart" runat="server" RepeatDirection="Horizontal" RepeatColumns="4" Height="343px" Width="1572px" onitemdatabound="dldepart_ItemDataBound"> 
    <ItemTemplate> 
     <asp:DropDownList ID="ddlist" runat="server" AutoPostBack="true" onselectedindexchanged="ddlist_SelectedIndexChanged"> 
     </asp:DropDownList> 
     <asp:CheckBoxList ID="CheckBoxList1" runat="server"> 
     </asp:CheckBoxList> 
    </ItemTemplate> 
</asp:DataList> 

ASP.NET C＃代码

private void BindCheckBoxList() 
{ 
    DataSet ds = new DataSet(); 
    DataTable dt = new DataTable(); 

    SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=D:\database\personal.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True"); 

    try 
    { 
     con.Open(); 

     SqlCommand Cmd = new SqlCommand("SELECT distinct depart FROM datalist", con); 
     SqlDataAdapter Da = new SqlDataAdapter(Cmd); 

     Da.Fill(dt); 
     if (dt.Rows.Count > 0) 
     { 
      dldepart.DataSource = dt; 
      dldepart.DataBind(); 
     } 
    } 
    catch (System.Data.SqlClient.SqlException ex) 
    { 
     string msg = "Fetch Error:"; 
     msg += ex.Message; 
     throw new Exception(msg); 
    } 
    finally 
    { 
     con.Close(); 
    } 
} 

protected void dldepart_ItemDataBound(object sender, DataListItemEventArgs e) 
{ 
    DropDownList ddlist = (DropDownList)e.Item.FindControl("ddlist"); 
    DataSet ds = new DataSet(); 
    DataTable dt = new DataTable(); 

    SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=D:\database\personal.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True"); 

    try 
    { 
     con.Open(); 

     SqlCommand Cmd = new SqlCommand("SELECT distinct depart FROM datalist", con); 
     SqlDataAdapter Da = new SqlDataAdapter(Cmd); 

     /**codes that i used to repeat datalist **/ 
     Da.Fill(dt); 
     if (dt.Rows.Count > 0) 
     { 
      ddlist.DataSource=dt; 
      ddlist.DataTextField="depart"; 
      ddlist.DataValueField="depart"; 
      ddlist.DataBind(); 
      ddlist.Items.Insert(0, "Select"); 
      ddlist.Items.FindByText("Select").Value = Convert.ToString(0); 
     } 
    } 
     catch (System.Data.SqlClient.SqlException ex) 
    { 

    } 
    finally 
    { 
     con.Close(); 
    } 
} 

在SelectedIndexChange

protected void ddlist_SelectedIndexChanged(object sender, EventArgs e) 
{ 
    DataListItem dlitem = (DataListItem)((DropDownList)sender).Parent; 
    CheckBoxList CheckBoxList1 = (CheckBoxList)dlitem.FindControl("CheckBoxList1"); 
    DropDownList ddlist = (DropDownList)dlitem.FindControl("ddlist"); 
    // DataBoundControl DataSource = (DataBind)dldepart.FindControl("DataSource"); 
    DataSet ds = new DataSet(); 
    DataTable dt = new DataTable(); 

    SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=D:\database\personal.mdf;Integrated Security=True;Connect Timeout=30;User Instance=True"); 

    try 
    { 
     con.Open(); 

     SqlCommand Cmd = new SqlCommand("SELECT Id,subDepatment FROM datalist where depart='" + ddlist.SelectedItem.Text + "'", con); 
     SqlDataAdapter Da = new SqlDataAdapter(Cmd); 

     Da.Fill(dt); 
     if (dt.Rows.Count > 0) 
     { 
      CheckBoxList1.DataSource = dt; 
      CheckBoxList1.DataTextField = "subDepatment"; // the items to be displayed in the list items 
      CheckBoxList1.DataValueField = "Id"; // the id of the items displayed 
      CheckBoxList1.DataBind(); 
     } 
    } 
    catch (System.Data.SqlClient.SqlException ex) 
    { 

    } 
    finally 
    { 
     con.Close(); 
    } 
} 

Answer 1

您需要维护主集合，该主集合将保存下拉列表值和一个将保存选定值的集合。通过将过滤器应用为主集合 - 选定集合来绑定下拉菜单。只有在下拉值发生变化时，您才需要添加或删除选定的收藏集。

因此，考虑例如为 -

MasterList集合 - 财务，营销，推广 选集 - 空

现在，每一个下拉列表应用过滤器Masterlist - 选择和绑定。

因此，所有的下拉值营销，金融，促销。 您可以选择Marketing for first dropdown，然后选择可用的第二个下拉列表if = Masterlist - Selected = Finance and Promition。

如果你只是通过查询数据库绑定下拉菜单，那么它会很简单。

Answer 2

//我想这和它的工作

<script type="text/javascript"> 

    function funcCheck(obj) 
     { 
     var isSelected=false; 
     var selectedVal=$(obj).val(); 
     var ctrlId=$(obj).attr("id"); 
     alert(selectedVal); 
     alert($("[id*=ddlist]").length); 
     $("[id*=ddlist]").each(function(){ 
      if($.trim($(this).attr("id"))!=$.trim(ctrlId)) 
      { 
       if(selectedVal == $(this).val()) 
       { 
        isSelected=true; 
        return; 
       } 
      } 
     }); 
     if(isSelected) 
     { 
      alert("Value is already selected"); 
      $(obj).val(0); 
      return false; 
     } 
     } 
</script>