GridViewEditEventHandler Delegat

Definicja

Reprezentuje metodę, która obsługuje RowEditing zdarzenie kontrolki GridView .

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

Parametry

sender
Object

Źródło zdarzenia.

e
GridViewEditEventArgs

GridViewEditEventArgs Obiekt zawierający dane zdarzenia.

Przykłady

W poniższym przykładzie pokazano, jak programowo dodać delegata GridViewEditEventHandler do RowEditing zdarzenia kontrolki GridView .


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

    // Set the GridView control's properties.
    customersGridView.ID = "CustomersGridView";
    customersGridView.DataSourceID = "CustomersSqlDataSource";
    customersGridView.AutoGenerateColumns = true;
    customersGridView.AutoGenerateEditButton = true;
    customersGridView.AllowPaging = true;
    customersGridView.DataKeyNames = new String[] { "CustomerID" };
      
    // Programmatically register the event-handling method.
    customersGridView.RowEditing += new GridViewEditEventHandler(this.CustomersGridView_RowEditing);
        
    // Add the GridView control to the Controls collection
    // of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView);
        
  }

  void CustomersGridView_RowEditing(Object sender, GridViewEditEventArgs e)
  {

    // User the sender parameter to retrieve the GridView control
    // that raised the event.
    GridView customersGridView = (GridView)sender;
    
    // Get the country for the row being edited. For this example, the
    // country is contained in the seventh column (index 6). 
    String country = customersGridView.Rows[e.NewEditIndex].Cells[6].Text;

    // For this example, cancel the edit operation if the user attempts
    // to edit the record of a customer from the USA. 
    if (country == "USA")
    {
      // Cancel the edit operation.
      e.Cancel = true;
      Message.Text = "You cannot edit this record.";
    }
    else
    {
      Message.Text = "";
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewEditEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewEditEventHandler Example</h3>
          
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>
            
      <asp:placeholder id="GridViewPlaceHolder"
        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="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </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 Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        
    ' Create a new GridView control.
    Dim customersGridView As New GridView()

    ' Set the GridView control's properties.
    customersGridView.ID = "CustomersGridView"
    customersGridView.DataSourceID = "CustomersSqlDataSource"
    customersGridView.AutoGenerateColumns = True
    customersGridView.AutoGenerateEditButton = True
    customersGridView.AllowPaging = True
    Dim keyArray() As String = {"CustomerID"}
    customersGridView.DataKeyNames = keyArray
      
    ' Programmatically register the event-handling method.
    AddHandler customersGridView.RowEditing, AddressOf CustomersGridView_RowEditing
        
    ' Add the GridView control to the Controls collection
    ' of the PlaceHolder control.
    GridViewPlaceHolder.Controls.Add(customersGridView)
        
  End Sub

  Sub CustomersGridView_RowEditing(ByVal sender As Object, ByVal e As GridViewEditEventArgs)

    ' User the sender parameter to retrieve the GridView control
    ' that raised the event.
    Dim customersGridView As GridView = CType(sender, GridView)
    
    ' Get the country for the row being edited. For this example, the
    ' country is contained in the seventh column (index 6). 
    Dim country As String = customersGridView.Rows(e.NewEditIndex).Cells(6).Text

    ' For this example, cancel the edit operation if the user attempts
    ' to edit the record of a customer from the USA. 
    If country = "USA" Then
    
      ' Cancel the edit operation.
      e.Cancel = True
      Message.Text = "You cannot edit this record."
    
    Else
    
      Message.Text = ""
      
    End If
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewEditEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewEditEventHandler Example</h3>
          
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>
            
      <asp:placeholder id="GridViewPlaceHolder"
        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="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

W poniższym przykładzie pokazano, jak deklaratywnie dodać delegata GridViewEditEventHandler do RowEditing zdarzenia kontrolki GridView .


<%@ 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 CustomersGridView_RowEditing(Object sender, GridViewEditEventArgs e)
  {
    
    // Get the country for the row being edited. For this example, the
    // country is contained in the seventh column (index 6). 
    String country = CustomersGridView.Rows[e.NewEditIndex].Cells[6].Text;

    // For this example, cancel the edit operation if the user attempts
    // to edit the record of a customer from the Unites States. 
    if (country == "USA")
    {
      // Cancel the edit operation.
      e.Cancel = true;
      Message.Text = "You cannot edit this record.";
    }
    else
    {
      Message.Text = "";
    }
    
  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowEditing Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowEditing Example</h3>
          
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>
            
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames property as read-only.    -->
      <!-- No input controls are rendered for these columns in     -->
      <!-- edit mode.                                              -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogenerateeditbutton="true"
        allowpaging="true" 
        datakeynames="CustomerID"
        onrowediting="CustomersGridView_RowEditing"   
        runat="server">
      </asp:gridview>
            
      <!-- 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="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </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 CustomersGridView_RowEditing(ByVal sender As Object, ByVal e As GridViewEditEventArgs)
        
    ' Get the country for the row being edited. For this example, the
    ' country is contained in the seventh column (index 6). 
    Dim country As String = CustomersGridView.Rows(e.NewEditIndex).Cells(6).Text

    ' For this example, cancel the edit operation if the user attempts
    ' to edit the record of a customer from the United States. 
    If country = "USA" Then
    
      ' Cancel the edit operation.
      e.Cancel = True
      Message.Text = "You cannot edit this record."
     
    Else
      
      Message.Text = ""
      
    End If
    
  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowEditing Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowEditing Example</h3>
          
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>
            
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames property as read-only.    -->
      <!-- No input controls are rendered for these columns in     -->
      <!-- edit mode.                                              -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogenerateeditbutton="true"
        allowpaging="true" 
        datakeynames="CustomerID"
        onrowediting="CustomersGridView_RowEditing"   
        runat="server">
      </asp:gridview>
            
      <!-- 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="CustomersSqlDataSource"  
        selectcommand="Select [CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country] From [Customers]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

Uwagi

Zdarzenie RowEditing jest wywoływane, gdy zostanie kliknięty przycisk Edytuj (przycisk z właściwością CommandName ustawioną na "Edytuj"), ale zanim kontrolka GridView przejdzie w tryb edycji. Dzięki temu można podać metodę obsługi zdarzeń, która wykonuje niestandardową procedurę, taką jak anulowanie operacji edycji, za każdym razem, gdy wystąpi to zdarzenie.

Podczas tworzenia delegata należy zidentyfikować metodę GridViewEditEventHandler , 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