IWebPartRow.GetRowData(RowCallback) 方法
定义
重要
一些信息与预发行产品相关,相应产品在发行之前可能会进行重大修改。 对于此处提供的信息,Microsoft 不作任何明示或暗示的担保。
返回行的数据,接口将使用该行作为两个 WebPart 控件之间的连接基础。
public:
void GetRowData(System::Web::UI::WebControls::WebParts::RowCallback ^ callback);
public void GetRowData (System.Web.UI.WebControls.WebParts.RowCallback callback);
abstract member GetRowData : System.Web.UI.WebControls.WebParts.RowCallback -> unit
Public Sub GetRowData (callback As RowCallback)
参数
- callback
- RowCallback
一个 RowCallback 委托,包含接收数据的方法的地址。
示例
下面的代码示例演示 方法的 GetRowData 实现和使用。 接口的类概述 IWebPartRow 中显示了完整的示例。 提供程序控件实现 GetRowData 方法,返回数据表中特定行的值。 使用者控件在其 OnPreRender
方法中调用 GetRowData 方法,以便可以将数据的值写入页面。
using System;
using System.Collections;
using System.ComponentModel;
using System.Data;
using System.Reflection;
using System.Security.Permissions;
using System.Web;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
namespace Samples.AspNet.CS.Controls
{
// This sample code creates a Web Parts control that acts as a provider
// of row data.
[AspNetHostingPermission(SecurityAction.Demand,
Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand,
Level = AspNetHostingPermissionLevel.Minimal)]
public sealed class RowProviderWebPart : WebPart, IWebPartRow
{
private DataTable _table;
public RowProviderWebPart()
{
_table = new DataTable();
DataColumn col = new DataColumn();
col.DataType = typeof(string);
col.ColumnName = "Name";
_table.Columns.Add(col);
col = new DataColumn();
col.DataType = typeof(string);
col.ColumnName = "Address";
_table.Columns.Add(col);
col = new DataColumn();
col.DataType = typeof(int);
col.ColumnName = "ZIP Code";
_table.Columns.Add(col);
DataRow row = _table.NewRow();
row["Name"] = "John Q. Public";
row["Address"] = "123 Main Street";
row["ZIP Code"] = 98000;
_table.Rows.Add(row);
}
[ConnectionProvider("Row")]
public IWebPartRow GetConnectionInterface()
{
return new RowProviderWebPart();
}
public PropertyDescriptorCollection Schema
{
get
{
return TypeDescriptor.GetProperties(_table.DefaultView[0]);
}
}
public void GetRowData(RowCallback callback)
{
callback(_table.Rows);
}
} // RowProviderWebPart
// This sample code creates a Web Parts control that acts as a consumer
// of row data.
[AspNetHostingPermission(SecurityAction.Demand,
Level = AspNetHostingPermissionLevel.Minimal)]
[AspNetHostingPermission(SecurityAction.InheritanceDemand,
Level = AspNetHostingPermissionLevel.Minimal)]
public sealed class RowConsumerWebPart : WebPart
{
private IWebPartRow _provider;
private ICollection _tableData;
private void GetRowData(object rowData)
{
_tableData = (ICollection)rowData;
}
protected override void OnPreRender(EventArgs e)
{
if (_provider != null)
{
_provider.GetRowData(new RowCallback(GetRowData));
}
}
protected override void RenderContents(HtmlTextWriter writer)
{
if (_provider != null)
{
PropertyDescriptorCollection props = _provider.Schema;
int count = 0;
if (props != null && props.Count > 0 && _tableData != null)
{
foreach (PropertyDescriptor prop in props)
{
foreach (DataRow o in _tableData)
{
writer.Write(prop.DisplayName + ": " + o[count]);
writer.WriteBreak();
writer.WriteLine();
count = count + 1;
}
}
}
else
{
writer.Write("No data");
}
}
else
{
writer.Write("Not connected");
}
}
[ConnectionConsumer("Row")]
public void SetConnectionInterface(IWebPartRow provider)
{
_provider = provider;
}
} // RowConsumerWebPart
} // Samples.AspNet.CS.Controls
Imports System.Collections
Imports System.ComponentModel
Imports System.Data
Imports System.Reflection
Imports System.Security.Permissions
Imports System.Web
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Namespace Samples.AspNet.VB.Controls
' This sample code creates a Web Parts control that acts as a provider
' of row data.
<AspNetHostingPermission(SecurityAction.Demand, _
Level:=AspNetHostingPermissionLevel.Minimal)> _
<AspNetHostingPermission(SecurityAction.InheritanceDemand, _
Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class RowProviderWebPart
Inherits WebPart
Implements IWebPartRow
Private _table As DataTable
Public Sub New()
_table = New DataTable()
Dim col As New DataColumn()
col.DataType = GetType(String)
col.ColumnName = "Name"
_table.Columns.Add(col)
col = New DataColumn()
col.DataType = GetType(String)
col.ColumnName = "Address"
_table.Columns.Add(col)
col = New DataColumn()
col.DataType = GetType(Integer)
col.ColumnName = "ZIP Code"
_table.Columns.Add(col)
Dim row As DataRow = _table.NewRow()
row("Name") = "John Q. Public"
row("Address") = "123 Main Street"
row("ZIP Code") = 98000
_table.Rows.Add(row)
End Sub
<ConnectionProvider("Row")> _
Public Function GetConnectionInterface() As IWebPartRow
Return New RowProviderWebPart()
End Function 'GetConnectionInterface
Public ReadOnly Property Schema() As _
ComponentModel.PropertyDescriptorCollection Implements IWebPartRow.Schema
Get
Return TypeDescriptor.GetProperties(_table.DefaultView(0))
End Get
End Property
Public Sub GetRowData(ByVal callback As RowCallback) _
Implements IWebPartRow.GetRowData
callback(_table.Rows)
End Sub
End Class
' This sample code creates a Web Parts control that acts as a consumer
' of row data.
<AspNetHostingPermission(SecurityAction.Demand, _
Level:=AspNetHostingPermissionLevel.Minimal)> _
<AspNetHostingPermission(SecurityAction.InheritanceDemand, _
Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class RowConsumerWebPart
Inherits WebPart
Private _provider As IWebPartRow
Private _tableData As ICollection
Private Sub GetRowData(ByVal rowData As Object)
_tableData = CType(rowData, ICollection)
End Sub
Protected Overrides Sub OnPreRender(ByVal e As EventArgs)
If Not (_provider Is Nothing) Then
_provider.GetRowData(New RowCallback(AddressOf GetRowData))
End If
End Sub
Protected Overrides Sub RenderContents(ByVal writer As HtmlTextWriter)
If Not (_provider Is Nothing) Then
Dim props As PropertyDescriptorCollection = _provider.Schema
Dim count As Integer = 0
If Not (props Is Nothing) AndAlso props.Count > 0 _
AndAlso Not (_tableData Is Nothing) Then
Dim prop As PropertyDescriptor
For Each prop In props
Dim o As DataRow
For Each o In _tableData
writer.Write(prop.DisplayName & ": " & o(count))
writer.WriteBreak()
writer.WriteLine()
count = count + 1
Next o
Next prop
Else
writer.Write("No data")
End If
Else
writer.Write("Not connected")
End If
End Sub
<ConnectionConsumer("Row")> _
Public Sub SetConnectionInterface(ByVal provider As IWebPartRow)
_provider = provider
End Sub
End Class
End Namespace ' Samples.AspNet.VB.Controls
注解
使用此方法检索接口传递的数据行值。 提供程序实现此方法,使用者在使用者准备好处理或呈现数据时调用此方法。