Question

寻找有关三重嵌套转发器逻辑问题的帮助。

背景
我正在构建一个时间表系统，用于预订从SQL Server数据库中提取数据的房间和资源。

表格结构

Table 1 - tblrooms  
room_id (INT) PK  
room_name (varchar(50))  
room_resource (INT)  

Table 2 - tblperiods  
period_id (INT) PK  
period_time_start (DATETIME)  
period_time_end (DATETIME)  
period_name (nvarchar(50))  

Table 3 - tblbookings  
booking_id (INT) PK  
period_id (INT)  
room_id (INT)  
booking_status (INT)  
booking_date (DATETIME)  
booking_subject (nvarchar(50))

问题我在很大程度上得到了中继器根据需要拉出数据但是只有第一列被填充，我真的很难找出如何拉出预订数据并根据需要建立时间表。 （请参阅附件截图我已经开始工作）

ASPX网页代码

<asp:Repeater ID="drPeriods" runat="server" OnItemDataBound="drPeriods_OnItemDataBound">

        <HeaderTemplate>
        <table class="table table-striped table-bordered table-condensed">
            <tr>
                <th style="width:16.66%"><asp:Label ID="lblResourceHeader" runat="server" /></th>
        </HeaderTemplate>

         <ItemTemplate>

                <th style="width:16.66%"><asp:Label ID="lblPeriod" runat="server" Text='<%# Eval("period_name") %>' /> - <asp:Label ID="lblPeriodStart" runat="server" Text='<%# Eval("period_time_start") %>' /> to <asp:Label ID="lblPeriodEnd" runat="server" Text='<%# Eval("period_time_end") %>' /></th>

         </ItemTemplate>

         <FooterTemplate>
             </tr> 

             <asp:Repeater ID="drResources" runat="server" OnItemDataBound="drResources_OnItemDataBound">

                    <ItemTemplate>

                    <tr>
                        <td height="50">
                            <asp:Label ID="lblResource" runat="server" Text='<%# Eval("room_name") %>' />
                            <br /><asp:Label ID="lblResourceDetails" runat="server" />
                        </td>
                        <asp:Label ID="lblFreeBooking" runat="server" Visible="false" />

                        <asp:Repeater ID="drBookings" runat="server" OnItemDataBound="drBookings_OnItemDataBound">

                            <ItemTemplate>

                                <td height="50">
                                    <asp:Label ID="lblCellContent" runat="server" />
                                </td>

                            </ItemTemplate>

                        </asp:Repeater>

                    </tr>

                    </ItemTemplate>

                </asp:Repeater>

            </table>

         </FooterTemplate>

     </asp:Repeater>

代码背后

Namespace Staff

Public Class Rb
    Inherits System.Web.UI.Page
    Private _periodId As Integer


    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load

        If Not IsPostBack Then

            txtDate.Text = Request.QueryString("d")

            'check for weekend dates, show message if it is.
            Dim iWeekday As Integer = Weekday(Request.QueryString("d"))

            If iWeekday = 1 Or iWeekday = 7 Then

                lblMsg.Text = "<div class='alert alert-info alert-block'><h4 class='alert-heading'><i class='icon-warning-sign'></i>&nbsp;It's the weekend.</h4><p>The date you have choosen is a weekend, resources cannot be booked on weekends.</p></div>"
                lblMsg.Visible = True
                drPeriods.Visible = False

            Else

                Dim objConnection As SqlConnection
                Dim objCommand As SqlCommand
                Dim objDataReader As SqlDataReader

                objConnection = New SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings("OPSDConnectionString").ConnectionString)

                'Get Periods
                objCommand = New SqlCommand("SELECT period_id, CONVERT(char(5), period_time_start, 108) AS period_time_start, CONVERT(char(5), period_time_end, 108) AS period_time_end, period_name FROM tblrb_periods", objConnection)

                Try
                    objConnection.Open()
                    objDataReader = objCommand.ExecuteReader()

                    If objDataReader.HasRows Then

                        drPeriods.DataSource = objDataReader
                        drPeriods.DataBind()
                        objDataReader.Close()

                    Else

                        drPeriods.Visible = False
                        lblMsg.Text = "<div class='alert alert-error alert-block'><h4 class='alert-heading'><i class='icon-warning-sign'></i>&nbsp;Error!</h4><p>Periods have not yet been setup, please set these up by selecting the periods tab above, if you cannot see this tab please ask the helpdesk administrator to set these up for you.</p></div>"
                        lblMsg.Visible = True
                        objDataReader.Close()

                    End If

                Catch ex As Exception

                    'Inform of the error
                    Elmah.ErrorSignal.FromCurrentContext().Raise(ex)

                Finally
                    objCommand.Dispose()
                    objConnection.Close()
                    objConnection.Dispose()

                End Try

            End If

        End If

    End Sub

    Protected Sub drPeriods_OnItemDataBound(sender As Object, e As System.Web.UI.WebControls.RepeaterItemEventArgs) Handles drPeriods.ItemDataBound

        If e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem Then

            _periodId = e.Item.DataItem("period_id")

        End If

        If e.Item.ItemType = ListItemType.Header Then

            Dim lblResourceHeader As Label = drPeriods.Controls(0).Controls(0).FindControl("lblResourceHeader")
            Dim layoutView As Integer = Request.QueryString("v")
            Select Case layoutView
                Case 1 ' Rooms
                    lblResourceHeader.Text = "Rooms"
                Case 2 ' Resources
                    lblResourceHeader.Text = "Resources"
                Case 3 ' Both
                    lblResourceHeader.Text = "Rooms &amp; Resources"
                Case Else
                    lblResourceHeader.Text = "Rooms &amp; Resources"
            End Select

        End If

        If e.Item.ItemType = ListItemType.Footer Then

            Dim objConnection As SqlConnection
            Dim objCommand As SqlCommand
            Dim objDataReader As SqlDataReader

            'find repeater in the footer of drPeriods (repeater)
            Dim drResources As Repeater = drPeriods.Controls(drPeriods.Controls.Count - 1).Controls(0).FindControl("drResources")
            Dim layoutView As Integer = Request.QueryString("v")

            'Get Rooms
            objConnection = New SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings("OPSDConnectionString").ConnectionString)

            Select Case layoutView
                Case 1 ' Rooms
                    objCommand = New SqlCommand("SELECT * FROM tblrb_rooms WHERE room_resource = 1 ORDER BY room_name", objConnection)
                Case 2 ' Resources
                    objCommand = New SqlCommand("SELECT * FROM tblrb_rooms WHERE room_resource = 2 ORDER BY room_name", objConnection)
                Case 3 ' Both
                    objCommand = New SqlCommand("SELECT * FROM tblrb_rooms ORDER BY room_name", objConnection)
                Case Else
                    objCommand = New SqlCommand("SELECT * FROM tblrb_rooms ORDER BY room_name", objConnection)
            End Select

            Try
                objConnection.Open()
                objDataReader = objCommand.ExecuteReader()

                drResources.DataSource = objDataReader
                drResources.DataBind()
                objDataReader.Close()

            Catch ex As Exception

                'Inform of the error
                Elmah.ErrorSignal.FromCurrentContext().Raise(ex)

            Finally
                objCommand.Dispose()
                objConnection.Close()
                objConnection.Dispose()

            End Try

        End If

    End Sub

    Protected Sub drResources_OnItemDataBound(sender As Object, e As System.Web.UI.WebControls.RepeaterItemEventArgs)

        If e.Item.ItemType = ListItemType.Item Or e.Item.ItemType = ListItemType.AlternatingItem Then

            Dim lblResourceDetails As Label = e.Item.FindControl("lblResourceDetails")
            If e.Item.DataItem("room_resource") <> 2 Then
                lblResourceDetails.Text = "[ <a href='#' class='withajaxpopover' title='Room Details' data-load='resourceManagerViewDetails.aspx?id=" & e.Item.DataItem("room_id") & "'>View Room Details</a> ]"
            End If

            Dim objConnection As SqlConnection
            Dim objCommand As SqlCommand
            Dim objDataReader As SqlDataReader
            Dim drBookings As Repeater = e.Item.FindControl("drBookings")
            Dim lblFreeBooking As Label = e.Item.FindControl("lblFreeBooking")

            'Get Bookings
            objConnection = New SqlConnection(System.Configuration.ConfigurationManager.ConnectionStrings("OPSDConnectionString").ConnectionString)
            objCommand = New SqlCommand("SELECT tblrb_bookings.booking_status, tblrb_bookings.booking_subject, tblrb_bookings.booking_notes FROM tblrb_bookings WHERE (tblrb_bookings.room_id = @room_id) AND (tblrb_bookings.booking_date = @booking_date) AND (tblrb_bookings.period_id = @period_id)", objConnection)

            objCommand.Parameters.Add("@room_id", SqlDbType.Int, 10).Value = e.Item.DataItem("room_id")
            objCommand.Parameters.Add("@period_id", SqlDbType.Int, 10).Value = _periodId
            objCommand.Parameters.Add("@booking_date", SqlDbType.DateTime).Value = Request.QueryString("d")

            Try
                objConnection.Open()
                objDataReader = objCommand.ExecuteReader()

                If objDataReader.HasRows Then

                    drBookings.DataSource = objDataReader
                    drBookings.DataBind()
                    objDataReader.Close()

                Else

                    'free period
                    lblFreeBooking.Text = "<td height='50'><div class='alert alert-block alert-success'><h4 class='alert-heading'><i class='icon-ok'></i>&nbsp;Free.</h4><p><a href='#'>Click here to book this resource.</a></p></div></td>"
                    lblFreeBooking.Visible = True

                End If

            Catch ex As Exception

                'Inform of the error
                Elmah.ErrorSignal.FromCurrentContext().Raise(ex)

            Finally
                objCommand.Dispose()
                objConnection.Close()
                objConnection.Dispose()

            End Try

        End If

    End Sub

    Protected Sub drBookings_OnItemDataBound(sender As Object, e As System.Web.UI.WebControls.RepeaterItemEventArgs)

        Dim lblCellContent As Label = e.Item.FindControl("lblCellContent")

        Select Case e.Item.DataItem("booking_status")
            Case 1
                'timetabled
                lblCellContent.Text = "<div class='alert alert-block alert-error'><h4 class='alert-heading'><i class='icon-warning-sign'></i>&nbsp;Timetabled.</h4><p>" & e.Item.DataItem("booking_subject") & "</p></div>"

            Case 2
                'user booked
                lblCellContent.Text = "<div class='alert alert-block'><h4 class='alert-heading'><i class='icon-warning-sign'></i>&nbsp;Booked.</h4><p>" & e.Item.DataItem("booking_subject") & ".</p></div>"

        End Select

    End Sub


    Protected Sub btnDateSelect_Click(sender As Object, e As System.EventArgs) Handles btnDateSelect.Click

        'quick reload of page
        Response.Redirect("resourceManager.aspx?v=" & Request.QueryString("v") & "&d=" & txtDate.Text)

    End Sub

End Class End Namespace

任何人都可以帮助我如何获得所需的布局，以便在构建时间表时，房间和时段包含相应列中每个单元格的正确预订数据。

提前感谢您提供的任何指示，花了3天时间，我可以用一双新鲜的眼睛： - ）

此致

奥奇

Repeater Data Issue

Answer 1

首先，我认为你的控制方式过于复杂。如果您使用LINQ或EF进行数据库访问，则可以使用2个嵌套转发器并且后面没有复杂的代码。但是，您可以将查询简化为以下内容：

SELECT *
FROM tblperiods p
    CROSS JOIN tblrooms r
    LEFT JOIN tblbookings b ON p.period_id = b.period_id AND r.room_id = b.room_id AND b.booking_date = '2012-08-01'

这将为您提供足够的信息，以便在给定日期的单个查询中生成整个输出。如果您不想使用EF或LINQ-to-SQL，您仍然可以使用一些LINQ魔法将其进一步分隔出来，然后您可以将其用于数据绑定（原谅C＃，VB.NET是有点生锈！）：

DataTable dt = new DataTable();
dt.Fill(objDataReader);          // Loads all data into the DataTable
var groupedRows = dt.Rows.Cast<DataRow>().GroupBy(row => new { RoomId = (int) row["room_id"], RoomName = (string) row["room_name"] });
rpRows.DataSource = groupedRows;
rpRows.DataBind();

那么你会有像这样的中继器：

<table>
<thead><tr><th>Rooms &amp; Resources</th>
<asp:Repeater runat="server" id="rpHeader">
    <ItemTemplate>
        <td><%# Eval("period_name") %></td>
    </ItemTemplate>
</asp:Repeater>
</tr></thead>
<asp:Repeater runat="server" id="rpRows">
    <ItemTemplate>
        <tr>
            <th><!-- Put room header stuff here --><%# Eval("Key.RoomName") %></th>
            <asp:Repeater runat="server" DataSource="<%# Container.DataItem %>">
                <ItemTemplate>
                    <td>
                         <!-- Per-booking info -->
                         <asp:Label runat="server" Visible='<%# Eval("booking_id") == DBNull.Value %>'>Not Booked</asp:label>
                         <asp:Label runat="server" Visible='<%# Eval("booking_id") != DBNull.Value %>'>Booked!</asp:label>
                    </td>
                </ItemTemplate>
            </asp:Repeater>
        </tr>
    </ItemTemplate>
</asp:Repeater>
</table>

我没有给出标题行数据绑定的代码，但这只是一个select * from tbl_periods

请注意，此代码均未经过测试，可能需要对数据绑定进行一些调整。

Answer 2

有一件事突然出现在我身上......

Dim drResources As Repeater = drPeriods.Controls(drPeriods.Controls.Count - 1).Controls(0).FindControl("drResources")

尝试用

之类的东西替换它

Dim drResources As Repeater = e.Item.FindControl("drResources")

（语法可能有点偏 - 我的VB很脆弱:)

我还会移除try catch，直到基础工作正常 - 可能是错误正在生成，但您从未见过它。

ASP.Net嵌套中继器逻辑地狱

2 个答案: