GridViewCommandEventHandler Delegat

Definicja

Reprezentuje metodę, która obsługuje RowCommand zdarzenie GridView formantu.Represents the method that handles the RowCommand event of a GridView control.

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

Parametry

sender
Object

Źródło zdarzenia.The source of the event.

e
GridViewCommandEventArgs

GridViewCommandEventArgsObiekt, który zawiera dane zdarzenia.A GridViewCommandEventArgs object that contains the event data.

Dziedziczenie
GridViewCommandEventHandler

Przykłady

W poniższym przykładzie pokazano, jak programowo dodać GridViewCommandEventHandler delegata do RowCommand zdarzenia GridView kontrolki.The following example demonstrates how to programmatically add a GridViewCommandEventHandler delegate to the RowCommand event of a GridView control.


<%@ 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 GridView object.
    GridView customersGridView = new GridView();

    // Set the GridView object's properties.
    customersGridView.ID = "CustomersGridView";
    customersGridView.DataSourceID = "CustomersSource";
    customersGridView.AutoGenerateColumns = false;

    // Dynamically create the columns for the GridView control.
    ButtonField addColumn = new ButtonField();
    addColumn.CommandName = "Add";
    addColumn.Text = "Add";
    addColumn.ButtonType = ButtonType.Link;

    BoundField companyNameColumn = new BoundField();
    companyNameColumn.DataField = "CompanyName";
    companyNameColumn.HeaderText = "Company Name";

    BoundField cityColumn = new BoundField();
    cityColumn.DataField = "City";
    cityColumn.HeaderText = "City";

    // Add the columns to the Columns collection
    // of the GridView control.
    customersGridView.Columns.Add(addColumn);
    customersGridView.Columns.Add(companyNameColumn);
    customersGridView.Columns.Add(cityColumn);

    // Programmatically register the event handling methods.
    customersGridView.RowCommand += new GridViewCommandEventHandler(this.CustomersGridView_RowCommand);
    customersGridView.RowCreated += new GridViewRowEventHandler(this.CustomersGridView_RowCreated);

    // Add the GridView object to the Controls collection
    // of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView);

  }

  void CustomersGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
  {
    // If multiple ButtonField columns are used, use the
    // CommandName property to determine which button was clicked.
    if(e.CommandName=="Add")
    {
      // Convert the row index stored in the CommandArgument
      // property to an Integer.
      int index = Convert.ToInt32(e.CommandArgument);

      // Retrieve the row that contains the button clicked
      // by the user from the Rows collection. Use the
      // CommandSource property to access the GridView control.
      GridView customersGridView = (GridView)e.CommandSource;
      GridViewRow row = customersGridView.Rows[index];

      // Create a new ListItem object for the customer in the row.
      ListItem item = new ListItem();
      item.Text = Server.HtmlDecode(row.Cells[1].Text) + " " + Server.HtmlDecode(row.Cells[2].Text);

      // If the author is not already in the ListBox, add the ListItem
      // object to the Items collection of a ListBox control.
      if(!CustomersListBox.Items.Contains(item))
      {
        CustomersListBox.Items.Add(item);
      }
    }
  }

  void CustomersGridView_RowCreated(Object sender, GridViewRowEventArgs e)
  {

    // The GridViewCommandEventArgs class does not contain a
    // property that indicates which row's command button was
    // clicked. To identify which row was clicked, use the button's
    // CommandArgument property by setting it to the row's index.
    if(e.Row.RowType == DataControlRowType.DataRow)
    {
      // Retrieve the LinkButton control from the first column.
      LinkButton addButton = (LinkButton)e.Row.Cells[0].Controls[0];

      // Set the LinkButton's CommandArgument property with the
      // row's index.
      addButton.CommandArgument = e.Row.RowIndex.ToString();
    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewCommandEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>GridViewCommandEventHandler Example</h3>

      <table width="100%">
        <tr>
          <td style="width:50%">
            <asp:placeholder id="GridViewPlaceHolder"
              runat="Server"/>
          </td>

          <td style="vertical-align:top; width:50%">
             Customers: <br/>
             <asp:listbox id="CustomersListBox"
               runat="server"/>
          </td>
        </tr>
      </table>

      <!-- 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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [City] 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 GridView object.
    Dim customersGridView As New GridView()

    ' Set the GridView object's properties.
    customersGridView.ID = "CustomersGridView"
    customersGridView.DataSourceID = "CustomersSource"
    customersGridView.AutoGenerateColumns = False

    ' Dynamically create the columns for the GridView control.
    Dim addColumn As New ButtonField()
    addColumn.CommandName = "Add"
    addColumn.Text = "Add"
    addColumn.ButtonType = ButtonType.Link

    Dim companyNameColumn As New BoundField()
    companyNameColumn.DataField = "CompanyName"
    companyNameColumn.HeaderText = "Company Name"

    Dim cityColumn As New BoundField()
    cityColumn.DataField = "City"
    cityColumn.HeaderText = "City"

    ' Add the columns to the Columns collection
    ' of the GridView control.
    customersGridView.Columns.Add(addColumn)
    customersGridView.Columns.Add(companyNameColumn)
    customersGridView.Columns.Add(cityColumn)

    ' Programmatically register the event handling methods.
    AddHandler customersGridView.RowCommand, AddressOf CustomersGridView_RowCommand
    AddHandler customersGridView.RowCreated, AddressOf CustomersGridView_RowCreated

    ' Add the GridView object to the Controls collection
    ' of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView)

  End Sub

  Sub CustomersGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)
  
    ' If multiple ButtonField columns are used, use the
    ' CommandName property to determine which button was clicked.
    If e.CommandName = "Add" Then
    
      ' Convert the row index stored in the CommandArgument
      ' property to an Integer.
      Dim index As Integer = Convert.ToInt32(e.CommandArgument)

      ' Retrieve the row that contains the button clicked
      ' by the user from the Rows collection. Use the
      ' CommandSource property to access the GridView control.
      Dim customersGridView As GridView = CType(e.CommandSource, GridView)
      Dim row As GridViewRow = customersGridView.Rows(index)

      ' Create a new ListItem object for the customer in the row.
      Dim item As New ListItem()
      item.Text = Server.HtmlDecode(row.Cells(1).Text) + " " + Server.HtmlDecode(row.Cells(2).Text)

      ' If the author is not already in the ListBox, add the ListItem
      ' object to the Items collection of a ListBox control.
      If Not CustomersListBox.Items.Contains(item) Then
      
        CustomersListBox.Items.Add(item)
        
      End If
    End If
        
  End Sub

  Sub CustomersGridView_RowCreated(ByVal sender As Object, ByVal e As GridViewRowEventArgs)

    ' The GridViewCommandEventArgs class does not contain a
    ' property that indicates which row's command button was
    ' clicked. To identify which row was clicked, use the button's
    ' CommandArgument property by setting it to the row's index.
    If e.Row.RowType = DataControlRowType.DataRow Then

      ' Retrieve the LinkButton control from the first column.
      Dim addButton As LinkButton = CType(e.Row.Cells(0).Controls(0), LinkButton)

      ' Set the LinkButton's CommandArgument property with the
      ' row's index.
      addButton.CommandArgument = e.Row.RowIndex.ToString()
      
    End If

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewCommandEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>GridViewCommandEventHandler Example</h3>

      <table width="100%">
        <tr>
          <td style="width:50%">
            <asp:placeholder id="GridViewPlaceHolder"
              runat="Server"/>
          </td>

          <td style="vertical-align:top; width:50%">
             Customers: <br/>
             <asp:listbox id="CustomersListBox"
               runat="server"/>
          </td>
        </tr>
      </table>

      <!-- 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="CustomersSource"
        selectcommand="Select [CustomerID], [CompanyName], [City] From [Customers]"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>

    </form>
  </body>
</html>

Poniższy przykład pokazuje, jak deklaratywnie dodać GridViewCommandEventHandler delegata do RowCommand zdarzenia GridView kontrolki.The following example demonstrates how to declaratively add a GridViewCommandEventHandler delegate to the RowCommand event of a GridView control.


<%@ 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 ContactsGridView_RowCommand(Object sender, GridViewCommandEventArgs e)
  {
    // If multiple buttons are used in a GridView control, use the
    // CommandName property to determine which button was clicked.
    if(e.CommandName=="Add")
    {
      // Convert the row index stored in the CommandArgument
      // property to an Integer.
      int index = Convert.ToInt32(e.CommandArgument);

      // Retrieve the row that contains the button clicked 
      // by the user from the Rows collection.
      GridViewRow row = ContactsGridView.Rows[index];

      // Create a new ListItem object for the contact in the row.     
      ListItem item = new ListItem();
      item.Text = Server.HtmlDecode(row.Cells[2].Text) + " " +
        Server.HtmlDecode(row.Cells[3].Text);

      // If the contact is not already in the ListBox, add the ListItem 
      // object to the Items collection of the ListBox control. 
      if (!ContactsListBox.Items.Contains(item))
      {
        ContactsListBox.Items.Add(item);
      }
    }
  }    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowCommand Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>GridView RowCommand Example</h3>

      <table width="100%">
        <tr>
          <td style="width:50%">

            <asp:gridview id="ContactsGridView" 
              datasourceid="ContactsSource"
              allowpaging="true" 
              autogeneratecolumns="false"
              onrowcommand="ContactsGridView_RowCommand"
              runat="server">

              <columns>
                <asp:buttonfield buttontype="Link" 
                  commandname="Add" 
                  text="Add"/>
                <asp:boundfield datafield="ContactID" 
                  headertext="Contact ID"/>
                <asp:boundfield datafield="FirstName" 
                  headertext="First Name"/> 
                <asp:boundfield datafield="LastName" 
                  headertext="Last Name"/>
              </columns>

            </asp:gridview>

          </td>

          <td style="vertical-align:top; width:50%">

            Contacts: <br/>
            <asp:listbox id="ContactsListBox"
              runat="server" Height="200px" Width="200px"/>

          </td>
        </tr>
      </table>

      <!-- This example uses Microsoft SQL Server and connects    -->
      <!-- to the AdventureWorks sample database. Use an ASP.NET  -->
      <!-- expression to retrieve the connection string value     -->
      <!-- from the Web.config file.                              -->
      <asp:sqldatasource id="ContactsSource"
        selectcommand="Select [ContactID], [FirstName], [LastName] From Person.Contact"
        connectionstring="<%$ ConnectionStrings:AdventureWorks_DataConnectionString%>" 
        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 ContactsGridView_RowCommand(ByVal sender As Object, ByVal e As GridViewCommandEventArgs)

    ' If multiple buttons are used in a GridView control, use the
    ' CommandName property to determine which button was clicked.
    If e.CommandName = "Add" Then
    
      ' Convert the row index stored in the CommandArgument
      ' property to an Integer.
      Dim index As Integer = Convert.ToInt32(e.CommandArgument)
            
      ' Retrieve the row that contains the button clicked 
      ' by the user from the Rows collection.
      Dim row As GridViewRow = ContactsGridView.Rows(index)
            
      ' Create a new ListItem object for the contact in the row.     
      Dim item As New ListItem()
      item.Text = Server.HtmlDecode(row.Cells(2).Text) & " " & _
        Server.HtmlDecode(row.Cells(3).Text)
            
      ' If the contact is not already in the ListBox, add the ListItem 
      ' object to the Items collection of the ListBox control. 
      If Not ContactsListBox.Items.Contains(item) Then
      
        ContactsListBox.Items.Add(item)
        
      End If
      
    End If
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head id="Head1" runat="server">
    <title>GridView RowCommand Example</title>
</head>
<body>
    <form id="form1" runat="server">

      <h3>GridView RowCommand Example</h3>

      <table width="100%">
        <tr>
          <td style="width:50%">

            <asp:gridview id="ContactsGridView" 
              datasourceid="ContactsSource"
              allowpaging="true" 
              autogeneratecolumns="false"
              onrowcommand="ContactsGridView_RowCommand"
              runat="server">

              <columns>
                <asp:buttonfield buttontype="Link" 
                  commandname="Add" 
                  text="Add"/>
                <asp:boundfield datafield="ContactID" 
                  headertext="Contact ID"/>
                <asp:boundfield datafield="FirstName" 
                  headertext="First Name"/> 
                <asp:boundfield datafield="LastName" 
                  headertext="Last Name"/>
              </columns>

            </asp:gridview>

          </td>

          <td style="vertical-align:top; width:50%">

            Contacts: <br/>
            <asp:listbox id="ContactsListBox"
              runat="server" Height="200px" Width="200px"/>

          </td>
        </tr>
      </table>

      <!-- This example uses Microsoft SQL Server and connects    -->
      <!-- to the AdventureWorks sample database. Use an ASP.NET  -->
      <!-- expression to retrieve the connection string value     -->
      <!-- from the Web.config file.                              -->
      <asp:sqldatasource id="ContactsSource"
        selectcommand="Select [ContactID], [FirstName], [LastName] From Person.Contact"
        connectionstring="<%$ ConnectionStrings:AdventureWorks_DataConnectionString%>" 
        runat="server"/>

    </form>
  </body>
</html>

Uwagi

RowCommandZdarzenie jest zgłaszane, gdy kliknięto przycisk w GridView kontrolce.The RowCommand event is raised when a button within the GridView control is clicked. Dzięki temu można podać metodę obsługi zdarzeń, która wykonuje procedurę niestandardową przy każdym wystąpieniu tego zdarzenia.This allows you to provide an event-handling method that performs a custom routine whenever this event occurs.

Uwaga

GridViewKontrolka wywołuje również inne wyspecjalizowane zdarzenia po kliknięciu pewnych przycisków (przyciski z CommandName właściwością ustawioną na na przykład "Delete", "Update" i "page").The GridView control also raises other specialized events when certain buttons are clicked (buttons with the CommandName property set to "Delete", "Update", and "Page" for example). W przypadku korzystania z jednego z tych przycisków należy rozważyć obsługę jednego ze specjalnych zdarzeń dostarczonych przez formant (na przykład RowDeleted lub RowDeleting ).When using one of these buttons, you should consider handling one of the specialized events provided by the control (such as RowDeleted or RowDeleting).

Podczas tworzenia GridViewCommandEventHandler delegata należy określić metodę, która będzie obsługiwać zdarzenie.When you create a GridViewCommandEventHandler delegate, you identify the method that will handle the event. Aby skojarzyć zdarzenie z programem obsługi zdarzeń, Dodaj wystąpienie delegata do zdarzenia.To associate the event with your event handler, add an instance of the delegate to the event. Program obsługi zdarzeń jest wywoływany przy każdym wystąpieniu zdarzenia, o ile nie usunięto delegata.The event handler is called whenever the event occurs, unless you remove the delegate. Aby uzyskać więcej informacji na temat delegatów obsługi zdarzeń, zobacz temat Obsługa iwywoływanie zdarzeń.For more information about event-handler delegates, see Handling and Raising Events.

Metody rozszerzania

GetMethodInfo(Delegate)

Pobiera obiekt, który reprezentuje metodę reprezentowaną przez określony delegat.Gets an object that represents the method represented by the specified delegate.

Dotyczy

Zobacz też