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IRowConsumer interface

NOTE: This API is now obsolete.

Permite que uma Web Part para se comunicar com uma Web Part que implementa a interface IRowProvider (ou que suporta um transformador adequado) para trabalhar com uma linha de dados.

Namespace:  Microsoft.SharePoint.WebPartPages.Communication
Assembly:  Microsoft.SharePoint (in Microsoft.SharePoint.dll)

Syntax

'Declaração
<ObsoleteAttribute("Use System.Web.UI.WebControls.WebParts.IWebPartRow instead")> _
Public Interface IRowConsumer
'Uso
Dim instance As IRowConsumer
[ObsoleteAttribute("Use System.Web.UI.WebControls.WebParts.IWebPartRow instead")]
public interface IRowConsumer

Comentários

A interface IRowConsumer deve ser implementada na Web Parts que precisa consumir um conjunto de dados que podem ser caracterizados como uma linha, como uma linha em uma tabela. A interface IRowConsumer tem a capacidade de receber argumentos de inicialização de Web Part do provedor. Ao se conectar a uma Web Part que implementa a interface IRowConsumer para um IRowProvider Web Parts, a conexão é direta, portanto nenhuma caixa de diálogo transformador será exibida. Para usar os valores passados corretamente, a Web Part consumindo talvez precise ser projetados com a compreensão do esquema dos dados sendo enviados pelo provedor de Web Part.

Examples

O exemplo de código a seguir mostra uma simples Web Part que implementa a interface IRowConsumer e oferece suporte à execução de sua implementação de conexão somente no servidor. Ele pode ser conectado a outra Web Part que implementa a interface IRowProvider no servidor. Sua interface de usuário exibe a linha de valores recebidos de IRowProvider Web Part.

Há sete etapas específicas para tornar isso uma Web Part conectável. Essas etapas são numeradas e comentadas no exemplo de código a seguir.

' Common .NET required namespaces
Imports System
Imports System.ComponentModel
Imports System.Web.UI

' Web Part required namespaces
Imports Microsoft.SharePoint.WebPartPages
Imports System.Xml.Serialization
Imports System.Web.UI.WebControls

' Code Access Security namespaces
Imports System.Security
Imports Microsoft.SharePoint.Utilities

' DataRow namespace
Imports System.Data

'Step #1: Make a reference to the Communication namespace.
Imports Microsoft.SharePoint.WebPartPages.Communication

Namespace ConnectionCodeSamples
   'Step #2: Inherit from the WebPart base class and implement the IRowConsumer interface.
   
   Public Class ServerSideRowConsumer
      Inherits WebPart
      Implements IRowConsumer
      
      ' Declare variables for keeping track of connection state.
      Private _connected As Boolean = False
      Private _connectedWebPartTitle As String = String.Empty
      Private _registrationErrorMsg As String = "An error has occurred trying to register your connection interfaces."
      Private _registrationErrorOccurred As Boolean = False
      Private _notConnectedMsg As String = "NOT CONNECTED. To use this Web Part connect it to a Row Provider Web Part."
      Private _selectRowMsg As String = "Please select a row from the connected Row Provider Web Part."
      
      ' Declare variables for Web Part user interface.
      Private _connectedWebPartLabel As String = "Connected to Web Part"
      Private _selectionStatus As String = String.Empty
      
      ' Declare variables for row information.
      Private _rowFieldDisplayNames() As String
      Private _rowFieldValues(0) As DataRow
      
      ' Step #3: Override the EnsureInterfaces() method and call the 
      ' RegisterInterface method.
      Public Overrides Sub EnsureInterfaces()
         ' If your Web Part is installed in the bin directory and the Code Access Security (CAS) setting doesn't 
         ' allow Web Part Connections, an exception will be thrown. To 
         ' allow your Web Part to behave 
         ' well and continue working, a try/catch block should be used 
         ' when attempting to register interfaces.
         ' Web Part Connections will only work if the level attribute 
         ' of the <trust> tag in the 
         ' web.config file is set to WSS_Minimal, WSS_Medium, or Full. 
         ' By default a new SharePoint site
         ' is installed with the trust level set to WSS_Minimal.
         Try
            ' Register the IRowConsumer interface.
            ' <param name="interfaceName">Friendly name of the 
            ' interface that is being implemented.</param>
            ' <param name="interfaceType">Specifies which interface is 
            ' being implemented.</param>
            ' <param name="maxConnections">Defines how many times this 
            ' interface can be connected.</param>
            ' <param name="runAtOptions">Determines where the interface 
            ' can run.</param>
            ' <param name="interfaceObject">Reference to the object 
            ' that is implementing this interface.</param>
            ' <param name="interfaceClientReference">Name used to 
            ' reference the interface on the client. 
            ' This is a server side example so the value is set to 
            ' empty string.</param>
            ' <param name="menuLabel">Label for the interface that 
            ' appears in the UI</param>
            ' <param name="description">Description of the interface 
            ' that appears in the UI</param>
            ' <param name="allowCrossPageConnection">Specifies if the 
            ' interface can connect to a Web Part
            ' on a different page. This is an optional parameter with a 
            ' default of false. Note that only some 
            ' server side interfaces are allowed to connect across 
            ' pages by the Web Part infrastructure. 
            ' The IRowConsumer interface is not allowed to connect 
            ' across pages.</param>
            RegisterInterface("MyRowConsumerInterface", InterfaceTypes.IRowConsumer, WebPart.LimitOneConnection, ConnectionRunAt.Server, Me, "", "Consume Row From", "Consumes a single row from another Web Part.") 
         
         Catch se As SecurityException
            _registrationErrorOccurred = True
         End Try
      End Sub
      
      ' Step #4: Override the CanRunAt() method.
      ' CanRunAt() is called by the Web Part infrastructure during the 
      ' ASP.NET PreRender event
      ' to determine where the Web Part can run based on its current 
      ' configuration.
      Public Overrides Function CanRunAt() As ConnectionRunAt
         ' This Web Part can run on the server.
         Return ConnectionRunAt.Server
      End Function
      
      ' Step #5: Override the PartCommunicationConnect() method.
      ' PartCommunicationConnect() is called by the Web Part 
      ' infrastructure to notify the Web Part that it
      ' is connected during the ASP.NET PreRender event. Relevant 
      ' information is passed to the part such as 
      ' the interface it is connected over, the Web Part it is being 
      ' connected to, and where the part will be running, 
      ' either client or server side. 
      ' <param name="interfaceName">Friendly name of the interface that 
      ' is being connected</param>
      ' <param name="connectedPart">Reference to the other Web Part 
      ' that is being connected to</param>
      ' <param name="connectedInterfaceName">Friendly name of the 
      ' interface on the other Web Part</param>
      ' <param name="runAt">Where the interface should execute</param>
      Public Overrides Sub PartCommunicationConnect(interfaceName As String, connectedPart As WebPart, connectedInterfaceName As String, runAt As ConnectionRunAt)
         ' Keep track of the connection state.
         If interfaceName = "MyRowConsumerInterface" Then
            _connected = True
            _connectedWebPartTitle = SPEncode.HtmlEncode(connectedPart.Title)
         End If
      End Sub
      
      ' Step #6: Implement the RowProviderInit event handler.
      ' The connected provider part(s) will call this method during its 
      ' PartCommunicationInit phase
      ' to pass initialization information to the consumer Web Part.
      ' <param name="sender">Reference to the Consumer Web Part</param>
      ' <param name="rowProviderInitEventArgs">The args passed by the 
      ' provider Web Part</param>
      Public Sub RowProviderInit(sender As Object, rowProviderInitEventArgs As RowProviderInitEventArgs) _
         Implements IRowConsumer.RowProviderInit
         ' Store the field list
         _rowFieldDisplayNames = rowProviderInitEventArgs.FieldDisplayList
      End Sub
       
      ' Step #7: Implement the RowReady event handler.
      ' The connected provider part(s) will call this method during its 
      ' PartCommunicationMain phase
      ' to pass their primary data to the consumer Web Part.
      ' <param name="sender">Reference to the provider Web Part</param>
      ' <param name="rowReadyEventArgs">The args passed by the provider 
      ' Web Part</param>
      Public Sub RowReady(sender As Object, rowReadyEventArgs As RowReadyEventArgs) _
         Implements IRowConsumer.RowReady
         ' Store the row values.
         If Not (rowReadyEventArgs.Rows Is Nothing) Then
            If Not (rowReadyEventArgs.Rows(0) Is Nothing) Then
               _rowFieldValues(0) = rowReadyEventArgs.Rows(0)
            End If
         End If
         _selectionStatus = rowReadyEventArgs.SelectionStatus
      End Sub
      
      ' Render the Web Part.
      Protected Overrides Sub RenderWebPart(output As HtmlTextWriter)
         ' Check for connection interface registration error.
         If _registrationErrorOccurred Then
            output.Write(_registrationErrorMsg)
            Return
         End If
         
         ' Check if connected.
         If _connected Then
            Dim index As Integer = 0
            Dim fieldName As String
            
            ' Check if a row has been selected.
            If _selectionStatus = "Standard" Then
               ' Generate results table from received row.
               output.RenderBeginTag(HtmlTextWriterTag.Table)
               For index = 0 To _rowFieldDisplayNames.Length - 1
                  fieldName = _rowFieldDisplayNames(index)
                  
                  output.RenderBeginTag(HtmlTextWriterTag.Tr)
                  output.RenderBeginTag(HtmlTextWriterTag.Td)
                  output.RenderBeginTag(HtmlTextWriterTag.B)
                  output.Write((fieldName + ": "))
                  output.RenderEndTag() 'End <B>
                  output.RenderEndTag() 'End <TD>
                  output.RenderBeginTag(HtmlTextWriterTag.Td)
                  output.Write(_rowFieldValues(0)(fieldName).ToString())
                  output.RenderEndTag() 'End <TD>
                  output.RenderEndTag() 'End <TR>
               Next index
               output.RenderEndTag() 'End <Table>
            Else
               output.RenderBeginTag(HtmlTextWriterTag.B)
               output.Write(_selectRowMsg)
               output.RenderEndTag()
            End If
            
            ' Line break.
            output.RenderBeginTag(HtmlTextWriterTag.Br)
            output.RenderEndTag()
            
            ' Render the connected Web Part title.
            output.Write((_connectedWebPartLabel + ": "))
            output.RenderBeginTag(HtmlTextWriterTag.I)
            output.Write(_connectedWebPartTitle)
            output.RenderEndTag()
            output.Write("<br>")
         
         Else
            ' The Web Part isn't connected.
            output.Write(_notConnectedMsg)
         End If
      End Sub
   End Class
End Namespace
// Common .NET required namespaces
using System;
using System.ComponentModel;
using System.Web.UI;

// Web Part required namespaces
using Microsoft.SharePoint.WebPartPages;
using System.Xml.Serialization;
using System.Web.UI.WebControls;

// Code Access Security namespaces
using System.Security;
using Microsoft.SharePoint.Utilities;

// DataRow namespace
using System.Data;

//Step #1: Make a reference to the Communication namespace.
using Microsoft.SharePoint.WebPartPages.Communication;

namespace ConnectionCodeSamples
{
    //Step #2: Inherit from the WebPart base class and implement the IRowConsumer interface.
    public class ServerSideRowConsumer : WebPart, IRowConsumer
    {    

        // Declare variables for keeping track of connection state.
        private bool _connected = false;
        private string _connectedWebPartTitle = string.Empty;
        private string _registrationErrorMsg = "An error has occurred trying to register your connection interfaces.";
        private bool _registrationErrorOccurred = false;
        private string _notConnectedMsg = "NOT CONNECTED. To use this Web Part connect it to a Row Provider Web Part.";
        private string _selectRowMsg = "Please select a row from the connected Row Provider Web Part.";

        // Declare variables for Web Part user interface.
        private string _connectedWebPartLabel = "Connected to Web Part";
        private string _selectionStatus = string.Empty;

        // Declare variables for row information.
        private string[] _rowFieldDisplayNames;
        DataRow[] _rowFieldValues = new DataRow[1];

        // Step #3: Override the EnsureInterfaces() method and call the 
        // RegisterInterface method.
        public override void EnsureInterfaces()
        {
            // If your Web Part is installed in the bin directory and 
            // the Code Access Security (CAS) setting doesn't 
            // allow Web Part Connections, an exception will be thrown. 
            // To allow your Web Part to behave 
            // well and continue working, a try/catch block should be 
            // used when attempting to register interfaces.
            // Web Part Connections will only work if the level 
            // attribute of the <trust> tag in the 
            // web.config file is set to WSS_Minimal, WSS_Medium, or 
            // Full. By default a new SharePoint site
            // is installed with the trust level set to WSS_Minimal.
            try
            {
                // Register the IRowConsumer interface.
                // <param name="interfaceName">Friendly name of the 
                // interface that is being implemented.</param>
                // <param name="interfaceType">Specifies which 
                // interface is being implemented.</param>
                // <param name="maxConnections">Defines how many times 
                // this interface can be connected.</param>
                // <param name="runAtOptions">Determines where the 
                // interface can run.</param>
                // <param name="interfaceObject">Reference to the 
                // object that is implementing this interface.</param>
                // <param name="interfaceClientReference">Name used to 
                // reference the interface on the client. 
                // This is a server side example so the value is set to 
                // empty string.</param>
                // <param name="menuLabel">Label for the interface 
                // which appears in the UI</param>
                // <param name="description">Description of the 
                // interface which appears in the UI</param>
                // <param name="allowCrossPageConnection">Specifies if 
                // the interface can connect to a Web Part
                // on a different page. This is an optional parameter 
                // with a default of false. Note that only some 
                // server side interfaces are allowed to connect across 
                // pages by the Web Part infrastructure. 
                // The IRowConsumer interface is not allowed to connect 
                // across pages.</param>
                RegisterInterface("MyRowConsumerInterface",                 //InterfaceName    
                    InterfaceTypes.IRowConsumer,                            //InterfaceType
                    WebPart.LimitOneConnection,                             //MaxConnections
                    ConnectionRunAt.Server,                                 //RunAtOptions
                    this,                                                   //InterfaceObject
                    "",                                                     //InterfaceClientReference
                    "Consume Row From",                                     //MenuLabel
                    "Consumes a single row from another Web Part.");        //Description
            }
            catch(SecurityException se)
            {
                _registrationErrorOccurred = true;
            }
        }


        // Step #4: Override the CanRunAt() method.
        // CanRunAt() is called by the Web Part infrastructure during 
        // the ASP.NET PreRender event
        // to determine where the Web Part can run based on its current 
        // configuration.
        public override ConnectionRunAt CanRunAt()
        {
            // This Web Part can run on the server.
            return ConnectionRunAt.Server;
        }


        // Step #5: Override the PartCommunicationConnect() method.
        // PartCommunicationConnect() is called by the Web Part 
        // infrastructure to notify the Web Part that it
        // is connected during the ASP.NET PreRender event. Relevant 
        // information is passed to the part such as 
        // the interface it is connected over, the Web Part it is being 
        // connected to, and where the part will be running, 
        // either client or server side. 
        // <param name="interfaceName">Friendly name of the interface 
        // that is being connected</param>
        // <param name="connectedPart">Reference to the other Web Part 
        // that is being connected to</param>
        // <param name="connectedInterfaceName">Friendly name of the 
        // interface on the other Web Part</param>
        // <param name="runAt">Where the interface should 
        // execute</param>
        public override void PartCommunicationConnect(string interfaceName,
            WebPart connectedPart,
            string connectedInterfaceName,
            ConnectionRunAt runAt)
        {
            // Keep track of the connection state.
            if (interfaceName == "MyRowConsumerInterface")
            {
                _connected = true;
                _connectedWebPartTitle = SPEncode.HtmlEncode(connectedPart.Title);
            }
        }

        // Step #6: Implement the RowProviderInit event handler.
        // The connected provider part(s) will call this method during 
        // its PartCommunicationInit phase
        // to pass initialization information to the consumer Web Part.
        // <param name="sender">Reference to the Consumer Web 
        // Part</param>
        // <param name="rowProviderInitEventArgs">The args passed by 
        // the provider Web Part</param>
        public void RowProviderInit(object sender, RowProviderInitEventArgs rowProviderInitEventArgs)
        {
            // Store the field list
            _rowFieldDisplayNames = rowProviderInitEventArgs.FieldDisplayList;

        }

        // Step #7: Implement the RowReady event handler.
        // The connected provider part(s) will call this method during 
        // its PartCommunicationMain phase
        // to pass their primary data to the consumer Web Part.
        // <param name="sender">Reference to the provider Web 
        // Part</param>
        // <param name="rowReadyEventArgs">The args passed by the 
        // provider Web Part</param>
        public void RowReady(object sender, RowReadyEventArgs rowReadyEventArgs)
        {
            // Store the row values.
            if(rowReadyEventArgs.Rows!= null)
            {
               if(rowReadyEventArgs.Rows[0]!= null)
               {
                  _rowFieldValues[0] = rowReadyEventArgs.Rows[0];
                }
            }

            _selectionStatus = rowReadyEventArgs.SelectionStatus;
        }

        // Render the Web Part.
        protected override void RenderWebPart(HtmlTextWriter output)
        {
            // Check for connection interface registration error.
            if (_registrationErrorOccurred)
            {
                output.Write(_registrationErrorMsg);
                return;
            }

            // Check if connected.
            if(_connected)
            {
                int index = 0;
                string fieldName;

                // Check if a row has been selected.
                if (_selectionStatus == "Standard")
                {
                    // Generate results table from received row.
                    output.RenderBeginTag(HtmlTextWriterTag.Table);
                    for (index = 0; index < _rowFieldDisplayNames.Length; index++)
                    {
                        fieldName = _rowFieldDisplayNames[index];
                    
                        output.RenderBeginTag(HtmlTextWriterTag.Tr);
                        output.RenderBeginTag(HtmlTextWriterTag.Td);
                        output.RenderBeginTag(HtmlTextWriterTag.B);
                        output.Write(fieldName + ": ");
                        output.RenderEndTag(); //End <B>
                        output.RenderEndTag(); //End <TD>

                        output.RenderBeginTag(HtmlTextWriterTag.Td);
                        output.Write(_rowFieldValues[0][fieldName].ToString());
                        output.RenderEndTag(); //End <TD>
                        output.RenderEndTag(); //End <TR>
                    }
                    output.RenderEndTag(); //End <Table>
                }
                else
                {
                    output.RenderBeginTag(HtmlTextWriterTag.B);
                    output.Write(_selectRowMsg);
                    output.RenderEndTag();
                }


                // Line break.
                output.RenderBeginTag(HtmlTextWriterTag.Br);
                output.RenderEndTag();

                // Render the connected Web Part title.
                output.Write(_connectedWebPartLabel + ": ");
                output.RenderBeginTag(HtmlTextWriterTag.I);
                output.Write(_connectedWebPartTitle);
                output.RenderEndTag();
                output.Write("<br>");

            }
            else
            {
                // The Web Part isn't connected.
                output.Write(_notConnectedMsg);
            }
        }
    }
}

Ver também

Referência

IRowConsumer members

Microsoft.SharePoint.WebPartPages.Communication namespace