DetailsViewCommandEventHandler Delegát

  • Reference

Definice

Obor názvů:
System.Web.UI.WebControls
Sestavení:
System.Web.dll

Představuje metodu, která zpracovává ItemCommand událost DetailsView ovládacího prvku.

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

Parametry

sender
Object

Zdroj události

e
DetailsViewCommandEventArgs

A DetailsViewCommandEventArgs , který obsahuje data události.

Příklady

Následující příklad kódu ukazuje, jak programově přidat DetailsViewCommandEventHandler delegáta ItemCommand k události DetailsView ovládacího prvku. Tento příklad používá model kódování s jedním souborem.


<%@ page language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<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.AllowPaging = true;
    customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };

    // Add a button field to the DetailsView control.
    ButtonField field = new ButtonField();
    field.ButtonType = ButtonType.Link;
    field.CausesValidation = false;
    field.Text = "Add to List";
    field.CommandName="Add";

    customerDetailsView.Fields.Add(field);

    // Programmatically register the event-handling method
    // for the ItemDeleting event of a DetailsView control.
    customerDetailsView.ItemCommand 
      += new DetailsViewCommandEventHandler( 
      this.CustomerDetailsView_ItemCommand);

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

  }
  
  void CustomerDetailsView_ItemCommand(Object sender, 
    DetailsViewCommandEventArgs e)
  {

    // Use the CommandName property to determine which button
    // was clicked. 
    if (e.CommandName == "Add")
    {
      // Get the DetailsView control that raised the event.
      DetailsView customerDetailsView = (DetailsView)e.CommandSource;

      // Add the current customer to the customer list. 

      // Get the row that contains the company name. In this
      // example, the company name is in the second row (index 1)  
      // of the DetailsView control.
      DetailsViewRow row = customerDetailsView.Rows[1];

      // Get the company's name from the appropriate cell.
      // In this example, the company name is in the second cell  
      // (index 1) of the row.
      String name = row.Cells[1].Text;

      // Create a ListItem object with the company name.
      ListItem item = new ListItem(name);

      // Add the ListItem object to the ListBox, if the 
      // item doesn't already exist.
      if (!CustomerListBox.Items.Contains(item))
      {
        CustomerListBox.Items.Add(item);
      }

    }

  }
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewCommandEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>DetailsViewCommandEventHandler Example</h3>
      
      <!-- Use a PlaceHolder control as the container for the -->
      <!-- dynamically generated DetailsView control.         -->       
      <asp:placeholder id="DetailsViewPlaceHolder"
        runat="server"/>
      
      <br/><br/>
      
      Selected Customers:<br/>
      <asp:listbox id="CustomerListBox"
        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]"
        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">
<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.AllowPaging = True
    
    Dim keyArray() As String = {"CustomerID"}
    customerDetailsView.DataKeyNames = keyArray
    
    ' Add a button field to the DetailsView control.
    Dim field As New ButtonField()
    field.ButtonType = ButtonType.Link
    field.CausesValidation = False
    field.Text = "Add to List"
    field.CommandName = "Add"

    customerDetailsView.Fields.Add(field)

    ' Programmatically register the event-handling method
    ' for the ItemDeleting event of a DetailsView control.
    AddHandler customerDetailsView.ItemCommand, _
      AddressOf CustomerDetailsView_ItemCommand

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

  End Sub
  
  Sub CustomerDetailsView_ItemCommand(ByVal sender As Object, _
    ByVal e As DetailsViewCommandEventArgs)

    ' Use the CommandName property to determine which button
    ' was clicked. 
    If e.CommandName = "Add" Then

      ' Get the DetailsView control that raised the event.
      Dim customerDetailsView As DetailsView = _
        CType(e.CommandSource, DetailsView)

      ' Add the current customer to the customer list. 

      ' Get the row that contains the company name. In this
      ' example, the company name is in the second row (index 1)  
      ' of the DetailsView control.
      Dim row As DetailsViewRow = customerDetailsView.Rows(1)

      ' Get the company's name from the appropriate cell.
      ' In this example, the company name is in the second cell  
      ' (index 1) of the row.
      Dim name As String = row.Cells(1).Text

      ' Create a ListItem object with the company name.
      Dim item As New ListItem(name)

      ' Add the ListItem object to the ListBox, if the 
      ' item doesn't already exist.
      If Not CustomerListBox.Items.Contains(item) Then
      
        CustomerListBox.Items.Add(item)
        
      End If

    End If

  End Sub
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewCommandEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
    
      <h3>DetailsViewCommandEventHandler Example</h3>
      
      <!-- Use a PlaceHolder control as the container for the -->
      <!-- dynamically generated DetailsView control.         -->       
      <asp:placeholder id="DetailsViewPlaceHolder"
        runat="server"/>
      
      <br/><br/>
      
      Selected Customers:<br/>
      <asp:listbox id="CustomerListBox"
        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]"
        connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>  
  
    </form>
  </body>
</html>

Následující příklad kódu ukazuje verzi modelu kódování na pozadí z předchozího příkladu. Aby tento příklad fungoval, musíte následující kód zkopírovat do přidruženého souboru s kódem na pozadí.

<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!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 runat="server">
    <title>DetailsViewCommandEventHandler Example</title>
</head>
<body>
    <form id="Form1" runat="server">
    
      <h3>DetailsViewCommandEventHandler Example</h3>
      
      <!-- Use a PlaceHolder control as the container for the -->
      <!-- dynamically generated DetailsView control.         -->       
      <asp:placeholder id="DetailsViewPlaceHolder"
        runat="server"/>
      
      <br/><br/>
      
      Selected Customers:<br/>
      <asp:listbox id="CustomerListBox"
        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]"
        connectionstring="
          <%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>  
  
    </form>
  </body>
</html>

<%@ Page Language="VB" AutoEventWireup="false" CodeFile="DefaultVB.aspx.vb" Inherits="DefaultVB" %>

<!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 runat="server">
    <title>DetailsViewCommandEventHandler Example</title>
</head>
<body>
    <form id="Form1" runat="server">
    
      <h3>DetailsViewCommandEventHandler Example</h3>
      
      <!-- Use a PlaceHolder control as the container for the -->
      <!-- dynamically generated DetailsView control.         -->       
      <asp:placeholder id="DetailsViewPlaceHolder"
        runat="server"/>
      
      <br/><br/>
      
      Selected Customers:<br/>
      <asp:listbox id="CustomerListBox"
        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]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>  
  
    </form>
  </body>
</html>

Následující příklad kódu ukazuje soubor kódu na pozadí pro předchozí příklad.

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

public partial class _Default : System.Web.UI.Page 
{
    protected 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.AllowPaging = true;
        customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };

        // Add a button field to the DetailsView control.
        ButtonField field = new ButtonField();
        field.ButtonType = ButtonType.Link;
        field.CausesValidation = false;
        field.Text = "Add to List";
        field.CommandName = "Add";

        customerDetailsView.Fields.Add(field);

        // Programmatically register the event-handling method
        // for the ItemDeleting event of a DetailsView control.
        customerDetailsView.ItemCommand += new DetailsViewCommandEventHandler(this.CustomerDetailsView_ItemCommand);

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

    void CustomerDetailsView_ItemCommand(Object sender, DetailsViewCommandEventArgs e)
    {

        // Use the CommandName property to determine which button
        // was clicked. 
        if (e.CommandName == "Add")
        {
            // Get the DetailsView control that raised the event.
            DetailsView customerDetailsView = (DetailsView)sender;

            // Add the current customer to the customer list. 

            // Get the row that contains the company name. In this
            // example, the company name is in the second row (index 1)  
            // of the DetailsView control.
            DetailsViewRow row = customerDetailsView.Rows[1];

            // Get the company's name from the appropriate cell.
            // In this example, the company name is in the second cell  
            // (index 1) of the row.
            String name = row.Cells[1].Text;

            // Create a ListItem object with the company name.
            ListItem item = new ListItem(name);

            // Add the ListItem object to the ListBox, if the 
            // item doesn't already exist.
            if (!CustomerListBox.Items.Contains(item))
            {
                CustomerListBox.Items.Add(item);
            }
        }
    }
}

Partial Class DefaultVB
    Inherits System.Web.UI.Page

    Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs) Handles Me.Load

        ' 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.AllowPaging = True

        Dim keyArray() As String = {"CustomerID"}
        customerDetailsView.DataKeyNames = keyArray

        ' Add a button field to the DetailsView control.
        Dim field As New ButtonField()
        field.ButtonType = ButtonType.Link
        field.CausesValidation = False
        field.Text = "Add to List"
        field.CommandName = "Add"

        customerDetailsView.Fields.Add(field)

        ' Programmatically register the event-handling method
        ' for the ItemDeleting event of a DetailsView control.
        AddHandler customerDetailsView.ItemCommand, AddressOf CustomerDetailsView_ItemCommand

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

    End Sub

    Sub CustomerDetailsView_ItemCommand(ByVal sender As Object, ByVal e As DetailsViewCommandEventArgs)

        ' Use the CommandName property to determine which button
        ' was clicked. 
        If e.CommandName = "Add" Then

            ' Get the DetailsView control that raised the event.
            Dim customerDetailsView As DetailsView = CType(sender, DetailsView)

            ' Add the current customer to the customer list. 

            ' Get the row that contains the company name. In this
            ' example, the company name is in the second row (index 1)  
            ' of the DetailsView control.
            Dim row As DetailsViewRow = customerDetailsView.Rows(1)

            ' Get the company's name from the appropriate cell.
            ' In this example, the company name is in the second cell  
            ' (index 1) of the row.
            Dim name As String = row.Cells(1).Text

            ' Create a ListItem object with the company name.
            Dim item As New ListItem(name)

            ' Add the ListItem object to the ListBox, if the 
            ' item doesn't already exist.
            If Not CustomerListBox.Items.Contains(item) Then

                CustomerListBox.Items.Add(item)

            End If

        End If

    End Sub

End Class

Následující příklad kódu ukazuje, jak deklarativně přidat DetailsViewCommandEventHandler delegáta ItemCommand k události DetailsView ovládacího prvku.


<%@ Page Language="C#" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">

    void CustomerDetailView_ItemCommand(Object sender, DetailsViewCommandEventArgs e)
    {

        // Use the CommandName property to determine which button
        // was clicked. 
        if (e.CommandName == "Add")
        {

            // Add the current store to the contact list. 

            // Get the row that contains the store name. In this
            // example, the store name is in the second row (index 1)  
            // of the DetailsView control.
            DetailsViewRow row = CustomerDetailView.Rows[1];

            // Get the store's name from the appropriate cell.
            // In this example, the store name is in the second cell  
            // (index 1) of the row.
            String name = row.Cells[1].Text;

            // Create a ListItem object with the store's name.
            ListItem item = new ListItem(name);

            // Add the ListItem object to the ListBox, if the 
            // item doesn't already exist.
            if (!ContactListBox.Items.Contains(item))
            {
                ContactListBox.Items.Add(item);
            }

        }

    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>
            DetailsView ItemCommand Example</title>
</head>
<body>
    <form id="Form1" runat="server">
        <h3>
            DetailsView ItemCommand Example</h3>
        <asp:DetailsView ID="CustomerDetailView" 
            DataSourceID="DetailsViewSource"
            AutoGenerateRows="false" 
            DataKeyNames="CustomerID" 
            AllowPaging="true" 
            OnItemCommand="CustomerDetailView_ItemCommand"
            runat="server">
            
            <FieldHeaderStyle BackColor="Navy" ForeColor="White" />
            
            <Fields>
                <asp:BoundField DataField="CustomerID" HeaderText="Store ID" />
                <asp:BoundField DataField="CompanyName" HeaderText="Store Name" />
                <asp:BoundField DataField="City" HeaderText="City" />
                <asp:ButtonField CommandName="Add" Text="Add Contact" />
            </Fields>
        </asp:DetailsView>
        
        <hr />
        
        Contacts:<br />
        <asp:ListBox ID="ContactListBox" 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" runat="server" 
          ConnectionString=
            "<%$ ConnectionStrings:NorthWindConnectionString%>"
            InsertCommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
          SelectCommand="Select [CustomerID], [CompanyName], 
            [Address], [City], [PostalCode], [Country] From 
            [Customers]">
        </asp:SqlDataSource>
    </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">
<script runat="server">

  Sub CustomerDetailView_ItemCommand(ByVal sender As Object, ByVal e As DetailsViewCommandEventArgs)
    
        ' Use the CommandName property to determine which button
        ' was clicked. 
        If e.CommandName = "Add" Then

            ' Add the current store to the contact list. 
     
            ' Get the row that contains the store name. In this
            ' example, the store name is in the second row (index 1)  
            ' of the DetailsView control.
            Dim row As DetailsViewRow = CustomerDetailView.Rows(1)
      
            ' Get the store's name from the appropriate cell.
            ' In this example, the store name is in the second cell  
            ' (index 1) of the row.
            Dim name As String = row.Cells(1).Text

            ' Create a ListItem object with the store's name.
            Dim item As New ListItem(name)

            ' Add the ListItem object to the ListBox, if the 
            ' item doesn't already exist.
            If Not ContactListBox.Items.Contains(item) Then
      
                ContactListBox.Items.Add(item)
      
            End If
        
        End If
    
    End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>
            DetailsView ItemCommand Example</title>
</head>
<body>
    <form id="Form1" runat="server">
        <h3>
            DetailsView ItemCommand Example</h3>
        <asp:DetailsView ID="CustomerDetailView" 
            DataSourceID="DetailsViewSource"
            AutoGenerateRows="false" 
            DataKeyNames="CustomerID" 
            AllowPaging="true" 
            OnItemCommand="CustomerDetailView_ItemCommand"
            runat="server">
            
            <FieldHeaderStyle BackColor="Navy" ForeColor="White" />
            
            <Fields>
                <asp:BoundField DataField="CustomerID" HeaderText="Store ID" />
                <asp:BoundField DataField="CompanyName" HeaderText="Store Name" />
                <asp:BoundField DataField="City" HeaderText="City" />
                <asp:ButtonField CommandName="Add" Text="Add Contact" />
            </Fields>
        </asp:DetailsView>
        
        <hr />
        
        Contacts:<br />
        <asp:ListBox ID="ContactListBox" 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" runat="server" 
          ConnectionString=
            "<%$ ConnectionStrings:NorthWindConnectionString%>"
            InsertCommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
          SelectCommand="Select [CustomerID], [CompanyName], 
            [Address], [City], [PostalCode], [Country] From 
            [Customers]">
        </asp:SqlDataSource>
    </form>
</body>
</html>

Poznámky

Ovládací DetailsView prvek vyvolá ItemCommand událost, když kliknete na tlačítko v ButtonFieldpoli řádku , CommandFieldnebo TemplateField . To vám umožní poskytnout obslužnou rutinu události, která provádí vlastní rutinu pokaždé, když dojde k této události.

Poznámka

Ovládací DetailsView prvek vyvolá také další specializované události při kliknutí na určitá tlačítka (tlačítka s CommandName vlastností nastavenou na "Delete", "Insert", "Page" nebo "Update"). Při použití některého z těchto tlačítek byste měli zvážit použití některé ze specializovaných událostí poskytovaných ovládacím prvekem (například ItemDeleted nebo ItemDeleting).

Při vytváření delegáta DetailsViewCommandEventHandler identifikujete metodu, která bude zpracovávat událost. Pokud chcete událost přidružit k obslužné rutině události, přidejte do události instanci delegáta. Obslužná rutina události je volána při každém výskytu události, dokud neodeberete delegáta. Další informace o delegátech obslužné rutiny událostí najdete v tématu Zpracování a vyvolávání událostí.

Metody rozšíření

GetMethodInfo(Delegate)

Získá objekt, který představuje metodu reprezentovanou zadaným delegátem.

Platí pro

Viz také