IDataItemContainer IDataItemContainer IDataItemContainer IDataItemContainer Interface

定义

启用数据绑定控件容器来为简化的数据绑定操作标识数据项对象。Enables data-bound control containers to identify a data item object for simplified data-binding operations.

public interface class IDataItemContainer : System::Web::UI::INamingContainer
public interface IDataItemContainer : System.Web.UI.INamingContainer
type IDataItemContainer = interface
    interface INamingContainer
Public Interface IDataItemContainer
Implements INamingContainer
派生
实现

示例

下面的代码示例演示如何使用IDataItemContainer接口。The following code example demonstrates how to use the IDataItemContainer interface. 是显示表格格式数据的控件, 类似DataGrid于或GridView控件。 SimpleSpreadsheetControlThe SimpleSpreadsheetControl is a control that displays tabular-style data, similar to a DataGrid or GridView control. 它包含一组SimpleSpreadsheetRow对象。It contains a set of SimpleSpreadsheetRow objects.

SimpleSpreadsheetRow类是IDataItemContainer实现接口的容器类。The SimpleSpreadsheetRow class is a container class that implements the IDataItemContainer interface. 虽然在此示例中Data DataItem , data item 属性以直观命名, 但可以实现属性以映射到方法的任何属性或返回值。Although in this example the data item property is intuitively named Data, the DataItem property can be implemented to map to any property or return value of a method.

using System;
using System.Collections;
using System.Data.Common;
using System.Web.UI;
using System.Web.UI.WebControls;

namespace Samples.AspNet.CS
{
    public class SimpleSpreadsheetControl : CompositeDataBoundControl
    {
        protected Table table = new Table();

        public virtual TableRowCollection Rows
        {
            get
            {
                return table.Rows;
            }
        }

        protected override int CreateChildControls(IEnumerable dataSource, bool dataBinding)
        {

            int count = 0;
            // If dataSource is not null, iterate through it and
            // extract each element from it as a row, then
            // create a SimpleSpreadsheetRow and add it to the
            // rows collection.
            if (dataSource != null)
            {

                SimpleSpreadsheetRow row;
                IEnumerator e = dataSource.GetEnumerator();

                while (e.MoveNext())
                {
                    object datarow = e.Current;
                    row = new SimpleSpreadsheetRow(count, datarow);
                    this.Rows.Add(row);
                    ++count;
                }

                Controls.Add(table);
            }
            return count;
        }
    }

    //
    //
    public class SimpleSpreadsheetRow : TableRow, IDataItemContainer
    {
        private object data;
        private int _itemIndex;

        public SimpleSpreadsheetRow(int itemIndex, object o)
        {
            data = o;
            _itemIndex = itemIndex;
        }

        public virtual object Data
        {
            get
            {
                return data;
            }
        }
        object IDataItemContainer.DataItem
        {
            get
            {
                return Data;
            }
        }
        int IDataItemContainer.DataItemIndex
        {
            get
            {
                return _itemIndex;
            }
        }
        int IDataItemContainer.DisplayIndex
        {
            get
            {
                return _itemIndex;
            }
        }
        protected override void RenderContents(HtmlTextWriter writer)
        {

            if (Data != null)
            {
                if (Data is System.Data.Common.DbDataRecord)
                {
                    DbDataRecord temp = (DbDataRecord)Data;
                    for (int i = 0; i < temp.FieldCount; ++i)
                    {
                        writer.Write("<TD>");
                        writer.Write(temp.GetValue(i).ToString());
                        writer.Write("</TD>");
                    }
                }
                else
                    writer.Write("<TD>" + Data.ToString() + "</TD>");
            }

            else
                writer.Write("<TD>This is a test</TD>");
        }
    }
}
Imports System.Collections
Imports System.Data.Common
Imports System.Web.UI
Imports System.Web.UI.WebControls

Namespace Samples.AspNet.VB

    Public Class SimpleSpreadsheetControl
        Inherits CompositeDataBoundControl

        Protected table As New Table()

        Public Overridable ReadOnly Property Rows() As TableRowCollection
            Get
                Return table.Rows
            End Get
        End Property


        Protected Overrides Function CreateChildControls(ByVal dataSource As IEnumerable, ByVal dataBinding As Boolean) As Integer

            Dim count As Integer = 0
            ' If dataSource is not Nothing, iterate through it and
            ' extract each element from it as a row, then
            ' create a SimpleSpreadsheetRow and add it to the
            ' rows collection.
            If Not (dataSource Is Nothing) Then

                Dim row As SimpleSpreadsheetRow
                Dim e As IEnumerator = dataSource.GetEnumerator()

                While e.MoveNext()
                    Dim datarow As Object = e.Current
                    row = New SimpleSpreadsheetRow(count, datarow)
                    Me.Rows.Add(row)
                    count += 1
                End While

                Controls.Add(table)
            End If
            Return count
        End Function 'CreateChildControls
    End Class 'SimpleSpreadsheetControl


    Public Class SimpleSpreadsheetRow
        Inherits TableRow
        Implements IDataItemContainer

        Private dataObj As Object
        Private _itemIndex As Integer

        Public Sub New(ByVal itemIndex As Integer, ByVal o As Object)
            dataObj = o
            _itemIndex = itemIndex
        End Sub

        Public Overridable ReadOnly Property Data() As Object
            Get
                Return dataObj
            End Get
        End Property

        ReadOnly Property DataItem() As Object Implements IDataItemContainer.DataItem
            Get
                Return Data
            End Get
        End Property

        ReadOnly Property DataItemIndex() As Integer Implements IDataItemContainer.DataItemIndex
            Get
                Return _itemIndex
            End Get
        End Property

        ReadOnly Property DisplayIndex() As Integer Implements IDataItemContainer.DisplayIndex
            Get
                Return _itemIndex
            End Get
        End Property
        Protected Overrides Sub RenderContents(ByVal writer As HtmlTextWriter)

            If Not (Data Is Nothing) Then
                If TypeOf Data Is System.Data.Common.DbDataRecord Then
                    Dim temp As DbDataRecord = CType(Data, DbDataRecord)
                    Dim i As Integer

                    While i < temp.FieldCount
                        writer.Write("<TD>")
                        writer.Write(temp.GetValue(i).ToString())
                        writer.Write("</TD>")
                        i += 1
                    End While
                Else
                    writer.Write(("<TD>" + Data.ToString() + "</TD>"))
                End If

            Else
                writer.Write("<TD>This is a test</TD>")
            End If
        End Sub
    End Class 'SimpleSpreadsheetRow
End Namespace

下面的代码示例演示如何使用SimpleSpreadsheetControlAccessDataSource控件在 Access 数据库中显示数据。The following code example demonstrates how to use the SimpleSpreadsheetControl and AccessDataSource control to display data in an Access database.

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS"
    Assembly="Samples.AspNet.CS"  %>
<%@ Page language="c#" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>IDataItemContainer - C# Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">

      <aspSample:SimpleSpreadsheetControl
          id="SimpleSpreadsheet1"
          runat="server"
          datasourceid="AccessDataSource1" />

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataReader"
          datafile="Northwind.mdb"
          SelectCommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,
          ShippedDate FROM Orders WHERE EmployeeID = (SELECT EmployeeID 
          FROM Employees WHERE LastName = 'King')">
      </asp:accessdatasource>

    </form>
  </body>
</html>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB"
    Assembly="Samples.AspNet.VB" %>
<%@ Page language="vb" %>
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
  <head>
    <title>IDataItemContainer - VB Example</title>
  </head>
  <body>
    <form id="Form1" method="post" runat="server">

      <aspSample:SimpleSpreadsheetControl
          id="SimpleSpreadsheet1"
          runat="server"
          datasourceid="AccessDataSource1" />

      <asp:accessdatasource
          id="AccessDataSource1"
          runat="server"
          datasourcemode="DataReader"
          datafile="Northwind.mdb"
          SelectCommand="SELECT OrderID,CustomerID,OrderDate,RequiredDate,ShippedDate
          FROM Orders WHERE EmployeeID =
          (SELECT EmployeeID FROM Employees WHERE LastName = 'King')">
      </asp:accessdatasource>

    </form>
  </body>
</html>

注解

实现IDataItemContainer接口的容器类可以指定其属性为数据绑定操作 (如DataBinder与类的后期绑定) 标识数据项。Container classes that implement the IDataItemContainer interface can specify which of their properties identifies the data item for data-binding operations, such as late binding with the DataBinder class.

属性

DataItem DataItem DataItem DataItem

实现时,获取在简化的数据绑定操作中所使用的 objectWhen implemented, gets an object that is used in simplified data-binding operations.

DataItemIndex DataItemIndex DataItemIndex DataItemIndex

实现时,获取绑定到控件的数据项的索引。When implemented, gets the index of the data item bound to a control.

DisplayIndex DisplayIndex DisplayIndex DisplayIndex

实现时,获取在控件中所显示的数据项的位置。When implemented, gets the position of the data item as displayed in a control.

扩展方法

GetDefaultValues(INamingContainer) GetDefaultValues(INamingContainer) GetDefaultValues(INamingContainer) GetDefaultValues(INamingContainer)

为指定数据控件获取默认值的集合。Gets the collection of the default values for the specified data control.

GetMetaTable(INamingContainer) GetMetaTable(INamingContainer) GetMetaTable(INamingContainer) GetMetaTable(INamingContainer)

为指定数据控件获取表元数据。Gets the table metadata for the specified data control.

SetMetaTable(INamingContainer, MetaTable) SetMetaTable(INamingContainer, MetaTable) SetMetaTable(INamingContainer, MetaTable) SetMetaTable(INamingContainer, MetaTable)

为指定数据控件设置表元数据。Sets the table metadata for the specified data control.

SetMetaTable(INamingContainer, MetaTable, IDictionary<String,Object>) SetMetaTable(INamingContainer, MetaTable, IDictionary<String,Object>) SetMetaTable(INamingContainer, MetaTable, IDictionary<String,Object>) SetMetaTable(INamingContainer, MetaTable, IDictionary<String,Object>)

为指定数据控件设置表元数据和默认值映射。Sets the table metadata and default value mapping for the specified data control.

SetMetaTable(INamingContainer, MetaTable, Object) SetMetaTable(INamingContainer, MetaTable, Object) SetMetaTable(INamingContainer, MetaTable, Object) SetMetaTable(INamingContainer, MetaTable, Object)

为指定数据控件设置表元数据和默认值映射。Sets the table metadata and default value mapping for the specified data control.

TryGetMetaTable(INamingContainer, MetaTable) TryGetMetaTable(INamingContainer, MetaTable) TryGetMetaTable(INamingContainer, MetaTable) TryGetMetaTable(INamingContainer, MetaTable)

确定表元数据是否可用。Determines whether table metadata is available.

EnableDynamicData(INamingContainer, Type) EnableDynamicData(INamingContainer, Type) EnableDynamicData(INamingContainer, Type) EnableDynamicData(INamingContainer, Type)

为指定数据控件启用动态数据行为。Enables Dynamic Data behavior for the specified data control.

EnableDynamicData(INamingContainer, Type, IDictionary<String,Object>) EnableDynamicData(INamingContainer, Type, IDictionary<String,Object>) EnableDynamicData(INamingContainer, Type, IDictionary<String,Object>) EnableDynamicData(INamingContainer, Type, IDictionary<String,Object>)

为指定数据控件启用动态数据行为。Enables Dynamic Data behavior for the specified data control.

EnableDynamicData(INamingContainer, Type, Object) EnableDynamicData(INamingContainer, Type, Object) EnableDynamicData(INamingContainer, Type, Object) EnableDynamicData(INamingContainer, Type, Object)

为指定数据控件启用动态数据行为。Enables Dynamic Data behavior for the specified data control.

适用于

另请参阅