DetailsViewDeletedEventHandler Delegat

Definicja

Reprezentuje metodę, która obsługuje ItemDeleted zdarzenie kontrolki DetailsView .

public delegate void DetailsViewDeletedEventHandler(System::Object ^ sender, DetailsViewDeletedEventArgs ^ e);
public delegate void DetailsViewDeletedEventHandler(object sender, DetailsViewDeletedEventArgs e);
type DetailsViewDeletedEventHandler = delegate of obj * DetailsViewDeletedEventArgs -> unit
Public Delegate Sub DetailsViewDeletedEventHandler(sender As Object, e As DetailsViewDeletedEventArgs)

Parametry

sender
Object

Źródło zdarzenia.

e
DetailsViewDeletedEventArgs

Element DetailsViewDeletedEventArgs zawierający dane zdarzenia.

Przykłady

Poniższy przykład kodu pokazuje, jak programowo dodać delegata DetailsViewDeletedEventHandler do ItemDeleted zdarzenia kontrolki DetailsView .


<%@ 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" >
  
  <script runat="server">
  
    void Page_Load(Object sender, EventArgs e)
    {
      
      // Create a new DetailsView object.
      DetailsView customerDetailsView = new DetailsView();
      
      // Set the DetailsView object's properties.
      customerDetailsView.ID = "CustomerDetailsView";
      customerDetailsView.DataSourceID = "DetailsViewSource";
      customerDetailsView.AutoGenerateRows = true;
      customerDetailsView.AutoGenerateDeleteButton = true;
      customerDetailsView.AllowPaging = true;
      customerDetailsView.PagerSettings.Mode = 
        PagerButtons.NextPrevious;
      customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };

      // Programmatically register the event-handling method
      // for the ItemDeleted event of a DetailsView control.
      customerDetailsView.ItemDeleted += 
        new DetailsViewDeletedEventHandler(
        this.CustomerDetailView_ItemDeleted);

      // Add the DetailsView object to the Controls collection
      // of the PlaceHolder control.
      DetailsViewPlaceHolder.Controls.Add(customerDetailsView);

    }

    void CustomerDetailView_ItemDeleted(Object sender, 
      DetailsViewDeletedEventArgs e)
    {
      // Use the Exception property to determine whether an exception
      // occurred during the delete operation.
      if (e.Exception == null)
      {
        // Use the AffectedRows property to determine the numbers of
        // rows affected by the delete operation.
        if (e.AffectedRows == 1)
        {
          MessageLabel.Text = e.AffectedRows.ToString() 
            + " record deleted successfully.";
        }
        else
        {
          MessageLabel.Text = e.AffectedRows.ToString() 
            + " records deleted successfully.";
        }
      }
      else
      {
        // Insert the code to handle the exception.
        MessageLabel.Text = e.Exception.Message;

        // Use the ExceptionHandled property to indicate that the 
        // exception is already handled.
        e.ExceptionHandled = true;
      }
    }
  
  </script>
    
  <head runat="server">
    <title>DetailsViewDeletedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewDeletedEventHandler Example</h3>
        
        <!-- Use a PlaceHolder control as the container for the -->
        <!-- dynamically generated DetailsView control.         -->       
        <asp:PlaceHolder id="DetailsViewPlaceHolder"
          runat="server"/>
          
        <br/><br/>
        
        <asp:label id="MessageLabel"
          forecolor="Red"
          runat="server"/>
            
        <!-- This example uses Microsoft SQL Server and connects  -->
        <!-- to the Northwind sample database. Use an ASP.NET     -->
        <!-- expression to retrieve the connection string value   -->
        <!-- from the web.config file.                            -->
        <asp:sqldatasource id="DetailsViewSource"
          selectcommand="Select [CustomerID], [CompanyName], [Address], 
            [City], [PostalCode], [Country] From [Customers]"
          deletecommand="Delete [Customers] 
            Where [CustomerID]=@CustomerID"
          connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
          runat="server"/>
            
      </form>
  </body>
</html>

<%@ 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" >
  
  <script runat="server">
  
    Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
      
      ' Create a new DetailsView object.
      Dim customerDetailsView As New DetailsView()
      
      ' Set the DetailsView object's properties.
      customerDetailsView.ID = "CustomerDetailsView"
      customerDetailsView.DataSourceID = "DetailsViewSource"
      customerDetailsView.AutoGenerateRows = True
      customerDetailsView.AutoGenerateDeleteButton = True
      customerDetailsView.AllowPaging = True
      customerDetailsView.PagerSettings.Mode = _
        PagerButtons.NextPrevious
      
      Dim keyArray() As String = {"CustomerID"}
      customerDetailsView.DataKeyNames = keyArray

      ' Programmatically register the event-handling method
      ' for the ItemDeleted event of a DetailsView control.
      AddHandler customerDetailsView.ItemDeleted, _
        AddressOf CustomerDetailView_ItemDeleted

      ' Add the DetailsView object to the Controls collection
      ' of the PlaceHolder control.
      DetailsViewPlaceHolder.Controls.Add(customerDetailsView)

    End Sub

    Sub CustomerDetailView_ItemDeleted(ByVal sender As Object, _
      ByVal e As DetailsViewDeletedEventArgs)
  
      ' Use the Exception property to determine whether an exception
      ' occurred during the delete operation.
      If e.Exception Is Nothing Then
    
        ' Use the AffectedRows property to determine the numbers of
        ' rows affected by the delete operation.
        If e.AffectedRows = 1 Then
      
          MessageLabel.Text = e.AffectedRows.ToString() _
            & " record deleted successfully."
      
        Else
              
          MessageLabel.Text = e.AffectedRows.ToString() _
            & " records deleted successfully."
      
        End If
    
      Else
    
        ' Insert the code to handle the exception.
        MessageLabel.Text = e.Exception.Message
      
        ' Use the ExceptionHandled property to indicate that the 
        ' exception is already handled.
        e.ExceptionHandled = True
    
      End If
    
    End Sub
  
  </script>
    
  <head runat="server">
    <title>DetailsViewDeletedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewDeletedEventHandler Example</h3>
        
        <!-- Use a PlaceHolder control as the container for the -->
        <!-- dynamically generated DetailsView control.         -->       
        <asp:PlaceHolder id="DetailsViewPlaceHolder"
          runat="server"/>
          
        <br/><br/>
        
        <asp:label id="MessageLabel"
          forecolor="Red"
          runat="server"/>
            
        <!-- This example uses Microsoft SQL Server and connects  -->
        <!-- to the Northwind sample database. Use an ASP.NET     -->
        <!-- expression to retrieve the connection string value   -->
        <!-- from the web.config file.                            -->
        <asp:sqldatasource id="DetailsViewSource"
          selectcommand="Select [CustomerID], [CompanyName], [Address], 
            [City], [PostalCode], [Country] From [Customers]"
          deletecommand="Delete [Customers] 
            Where [CustomerID]=@CustomerID"
          connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
          runat="server"/>
            
      </form>
  </body>
</html>

W poniższym przykładzie kodu pokazano, jak deklaratywnie dodać delegata DetailsViewDeletedEventHandler do ItemDeleted zdarzenia kontrolki DetailsView .


<%@ 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" >
  
  <script runat="server">

    void CustomerDetailView_ItemDeleted(Object sender, 
      DetailsViewDeletedEventArgs e)
    {
      // Use the Exception property to determine whether an exception
      // occurred during the delete operation.
      if (e.Exception == null)
      {
        // Use the AffectedRows property to determine the numbers of
        // rows affected by the delete operation.
        if (e.AffectedRows == 1)
        {
          MessageLabel.Text = e.AffectedRows.ToString() 
            + " record deleted successfully.";
        }
        else
        {
          MessageLabel.Text = e.AffectedRows.ToString() 
            + " records deleted successfully.";
        }
      }
      else
      {
        // Insert the code to handle the exception.
        MessageLabel.Text = e.Exception.Message;

        // Use the ExceptionHandled property to indicate that the 
        // exception is already handled.
        e.ExceptionHandled = true;
      }
    }
  
  </script>
    
  <head runat="server">
    <title>DetailsViewDeletedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewDeletedEventHandler Example</h3>
        
        <asp:detailsview id="CustomerDetailsView"
          datasourceid="DetailsViewSource"
          autogeneraterows="true"
          autogeneratedeletebutton="true"
          allowpaging="true"
          datakeynames="CustomerID" 
          runat="server">
        
          <pagersettings mode="NextPrevious"/>
        
        </asp:detailsview>
          
        <br/><br/>
        
        <asp:label id="MessageLabel"
          forecolor="Red"
          runat="server"/>
            
        <!-- This example uses Microsoft SQL Server and connects  -->
        <!-- to the Northwind sample database. Use an ASP.NET     -->
        <!-- expression to retrieve the connection string value   -->
        <!-- from the web.config file.                            -->
        <asp:sqldatasource id="DetailsViewSource"
          selectcommand="Select [CustomerID], [CompanyName], [Address], 
            [City], [PostalCode], [Country] From [Customers]"
          deletecommand="Delete [Customers] 
            Where [CustomerID]=@CustomerID"
          connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
          runat="server"/>
            
      </form>
  </body>
</html>

<%@ 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" >
  
  <script runat="server">

    Sub CustomerDetailView_ItemDeleted(ByVal sender As Object, _
      ByVal e As DetailsViewDeletedEventArgs)
  
      ' Use the Exception property to determine whether an exception
      ' occurred during the delete operation.
      If e.Exception Is Nothing Then
    
        ' Use the AffectedRows property to determine the numbers of
        ' rows affected by the delete operation.
        If e.AffectedRows = 1 Then
      
          MessageLabel.Text = e.AffectedRows.ToString() _
            & " record deleted successfully."
      
        Else
              
          MessageLabel.Text = e.AffectedRows.ToString() _
            & " records deleted successfully."
      
        End If
    
      Else
    
        ' Insert the code to handle the exception.
        MessageLabel.Text = e.Exception.Message
      
        ' Use the ExceptionHandled property to indicate that the 
        ' exception is already handled.
        e.ExceptionHandled = True
    
      End If
    
    End Sub
  
  </script>
    
  <head runat="server">
    <title>DetailsViewDeletedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewDeletedEventHandler Example</h3>
        
        <asp:detailsview id="CustomerDetailsView"
          datasourceid="DetailsViewSource"
          autogeneraterows="true"
          autogeneratedeletebutton="true"
          allowpaging="true"
          datakeynames="CustomerID" 
          runat="server">
        
          <pagersettings mode="NextPrevious"/>
        
        </asp:detailsview>
          
        <br/><br/>
        
        <asp:label id="MessageLabel"
          forecolor="Red"
          runat="server"/>
            
        <!-- This example uses Microsoft SQL Server and connects  -->
        <!-- to the Northwind sample database. Use an ASP.NET     -->
        <!-- expression to retrieve the connection string value   -->
        <!-- from the web.config file.                            -->
        <asp:sqldatasource id="DetailsViewSource"
          selectcommand="Select [CustomerID], [CompanyName], [Address], 
            [City], [PostalCode], [Country] From [Customers]"
          deletecommand="Delete [Customers] 
            Where [CustomerID]=@CustomerID"
          connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
          runat="server"/>
            
      </form>
  </body>
</html>

Uwagi

Kontrolka DetailsView zgłasza ItemDeleted zdarzenie, gdy przycisk Usuń (przycisk ze swoją CommandName właściwością ustawioną na "Usuń") w kontrolce jest klikany, ale po usunięciu DetailsView rekordu przez kontrolkę. Dzięki temu można udostępnić procedurę obsługi zdarzeń, która wykonuje niestandardową procedurę, taką jak sprawdzanie wyników operacji usuwania, za każdym razem, gdy wystąpi to zdarzenie.

Podczas tworzenia delegata należy zidentyfikować metodę DetailsViewDeletedEventHandler , która będzie obsługiwać zdarzenie. Aby skojarzyć zdarzenie z programem obsługi zdarzeń, dodaj wystąpienie delegata do zdarzenia. Program obsługi zdarzeń jest wywoływany przy każdym wystąpieniu zdarzenia, o ile nie usunięto delegata. Aby uzyskać więcej informacji na temat delegatów programu obsługi zdarzeń, zobacz Obsługa i podnoszenie zdarzeń.

Metody rozszerzania

GetMethodInfo(Delegate)

Pobiera obiekt reprezentujący metodę reprezentowaną przez określonego delegata.

Dotyczy

Zobacz też