IWebPartRow.GetRowData(RowCallback) Method
Definition
Important
Some information relates to prerelease product that may be substantially modified before it’s released. Microsoft makes no warranties, express or implied, with respect to the information provided here.
Returns the data for the row that is being used by the interface as the basis of a connection between two WebPart controls.
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)
Parameters
- callback
- RowCallback
A RowCallback delegate that contains the address of a method that receives the data.
Examples
The following code example shows the implementation and use of the GetRowData method. The complete example is shown in the class overview for the IWebPartRow interface. The provider control implements the GetRowData method, returning the value of a particular row in the data table. The consumer control calls the GetRowData method in its OnPreRender
method, so that the value of the data can be written to the page.
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
Remarks
Use this method to retrieve the data row values passed by the interface. The provider implements this method, and the consumer invokes it at the point when the consumer is ready to process or render data.