GridView.RowCancelingEdit Zdarzenie

Definicja

Występuje, gdy kliknięto przycisk Anuluj wiersza w trybie edycji, ale przed opuszczeniem wiersza tryb edycji.Occurs when the Cancel button of a row in edit mode is clicked, but before the row exits edit mode.

public:
 event System::Web::UI::WebControls::GridViewCancelEditEventHandler ^ RowCancelingEdit;
public event System.Web.UI.WebControls.GridViewCancelEditEventHandler RowCancelingEdit;
member this.RowCancelingEdit : System.Web.UI.WebControls.GridViewCancelEditEventHandler 
Public Custom Event RowCancelingEdit As GridViewCancelEditEventHandler 

Typ zdarzenia

GridViewCancelEditEventHandler

Przykłady

Poniższy przykład ilustruje sposób użycia RowCancelingEdit zdarzenia w celu wyświetlenia komunikatu o anulowaniu, gdy użytkownik anuluje operację aktualizacji GridView formantu.The following example demonstrates how to use the RowCancelingEdit event to display a cancellation message when the user cancels the update operation 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 CustomersGridView_RowCancelingEdit(Object sender, GridViewCancelEditEventArgs e)
  {
    
    // Retrieve the row that raised the event from the Rows
    // collection of the GridView control.
    GridViewRow row = CustomersGridView.Rows[e.RowIndex];
    
    // The update operation was canceled. Display the 
    // primary key of the row. In this example, the primary
    // key is displayed in the second column of the GridView
    // control. To access the text of the column, use the Cells
    // collection of the row.
    Message.Text = "Update for item " + row.Cells[1].Text + " Canceled."; 
    
  }

  void CustomersGridView_RowEditing(Object sender, GridViewEditEventArgs e)
  {

    // The GridView control is entering edit mode. Clear the message label.
    Message.Text = "";

  }
  
  void CustomersGridView_RowUpdated(Object sender, GridViewUpdatedEventArgs e)
  {

    // The update operation was successful. Clear the message label.
    Message.Text = "";

  }
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowCancelingEdit Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowCancelingEdit Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>
      
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames attribute 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"
        onrowcancelingedit="CustomersGridView_RowCancelingEdit"
        onrowediting="CustomersGridView_RowEditing" 
        onrowupdated="CustomersGridView_RowUpdated"    
        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_RowCancelingEdit(ByVal sender As Object, ByVal e As GridViewCancelEditEventArgs)
    
    ' Retrieve the row that raised the event from the Rows
    ' collection of the GridView control.
    Dim row As GridViewRow = CustomersGridView.Rows(e.RowIndex)
    
    ' The update operation was canceled. Display the 
    ' primary key of the row. In this example, the primary
    ' key is displayed in the second column of the GridView
    ' control. To access the text of the column, use the Cells
    ' collection of the row.
    Message.Text = "Update for item " & row.Cells(1).Text & " Canceled."
    
  End Sub

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

    ' The GridView control is entering edit mode. Clear the message label.
    Message.Text = ""

  End Sub
  
  Sub CustomersGridView_RowUpdated(ByVal sender As Object, ByVal e As GridViewUpdatedEventArgs)
    
    ' The update operation was successful. Clear the message label.
    Message.Text = ""

  End Sub
    
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowCancelingEdit Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowCancelingEdit Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"
        runat="server"/>
                
      <br/>
      
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames attribute 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"
        onrowcancelingedit="CustomersGridView_RowCancelingEdit"
        onrowediting="CustomersGridView_RowEditing" 
        onrowupdated="CustomersGridView_RowUpdated"    
        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>

Poniższy przykład ilustruje sposób użycia RowCancelingEdit zdarzenia w celu anulowania operacji aktualizacji, gdy źródło danych jest ustawione programowo.The following example demonstrates how to use the RowCancelingEdit event to cancel the update operation when the data source is set programmatically.

<%@ Page Language="C#" %>
<%@ Import Namespace="System.Data" %>

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

<script runat="server">

  protected void Page_Load(object sender, EventArgs e)
  {
          
    if (!Page.IsPostBack)
    {
      // Create a new table.
      DataTable taskTable = new DataTable("TaskList");
      
      // Create the columns.
      taskTable.Columns.Add("Id", typeof(int));
      taskTable.Columns.Add("Description", typeof(string));
      taskTable.Columns.Add("IsComplete", typeof(bool) );

      //Add data to the new table.
      for (int i = 0; i < 20; i++)
      {
        DataRow tableRow = taskTable.NewRow();
        tableRow["Id"] = i;
        tableRow["Description"] = "Task " + i.ToString();
        tableRow["IsComplete"] = false;            
        taskTable.Rows.Add(tableRow);
      }

      //Persist the table in the Session object.
      Session["TaskTable"] = taskTable;

      //Bind data to the GridView control.
      BindData();
    }

  }

  protected void TaskGridView_PageIndexChanging(object sender, GridViewPageEventArgs e)
  {
    TaskGridView.PageIndex = e.NewPageIndex;
    //Bind data to the GridView control.
    BindData();
  }

  protected void TaskGridView_RowEditing(object sender, GridViewEditEventArgs e)
  {
    //Set the edit index.
    TaskGridView.EditIndex = e.NewEditIndex;
    //Bind data to the GridView control.
    BindData();
  }

  protected void TaskGridView_RowCancelingEdit(object sender, GridViewCancelEditEventArgs e)
  {
    //Reset the edit index.
    TaskGridView.EditIndex = -1;
    //Bind data to the GridView control.
    BindData();
  }

  protected void TaskGridView_RowUpdating(object sender, GridViewUpdateEventArgs e)
  {    
    //Retrieve the table from the session object.
    DataTable dt = (DataTable)Session["TaskTable"];

    //Update the values.
    GridViewRow row = TaskGridView.Rows[e.RowIndex];
    dt.Rows[row.DataItemIndex]["Id"] = ((TextBox)(row.Cells[1].Controls[0])).Text;
    dt.Rows[row.DataItemIndex]["Description"] = ((TextBox)(row.Cells[2].Controls[0])).Text;
    dt.Rows[row.DataItemIndex]["IsComplete"] = ((CheckBox)(row.Cells[3].Controls[0])).Checked;

    //Reset the edit index.
    TaskGridView.EditIndex = -1;

    //Bind data to the GridView control.
    BindData();
  }

  private void BindData()
  {
    TaskGridView.DataSource = Session["TaskTable"];
    TaskGridView.DataBind();
  }
</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>GridView example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
      <asp:GridView ID="TaskGridView" runat="server" 
        AutoGenerateEditButton="True" 
        AllowPaging="true"
        OnRowEditing="TaskGridView_RowEditing"         
        OnRowCancelingEdit="TaskGridView_RowCancelingEdit" 
        OnRowUpdating="TaskGridView_RowUpdating"
        OnPageIndexChanging="TaskGridView_PageIndexChanging">
      </asp:GridView>
    
    </div>
    </form>
</body>
</html>
<%@ Page Language="VB" %>
<%@ Import Namespace="System.Data" %>

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

<script runat="server">

  Protected Sub Page_Load()

    If Not Page.IsPostBack Then
      ' Create a new table.
      Dim taskTable As New DataTable("TaskList")

      ' Create the columns.
      taskTable.Columns.Add("Id", GetType(Integer))
      taskTable.Columns.Add("Description", GetType(String))
      taskTable.Columns.Add("IsComplete", GetType(Boolean))

      'Add data to the new table.
      For i = 0 To 19
        Dim tableRow = taskTable.NewRow()
        tableRow("Id") = i
        tableRow("Description") = "Task " + i.ToString()
        tableRow("IsComplete") = False
        taskTable.Rows.Add(tableRow)
      Next

      'Persist the table in the Session object.
      Session("TaskTable") = taskTable

      'Bind data to the GridView control.
      BindData()
    End If

  End Sub
  
  Protected Sub TaskGridView_PageIndexChanging(ByVal sender As Object, ByVal e As GridViewPageEventArgs)
    TaskGridView.PageIndex = e.NewPageIndex
    'Bind data to the GridView control.
    BindData()
  End Sub

  Protected Sub TaskGridView_RowEditing(ByVal sender As Object, ByVal e As GridViewEditEventArgs)
    'Set the edit index.
    TaskGridView.EditIndex = e.NewEditIndex
    'Bind data to the GridView control.
    BindData()
  End Sub

  Protected Sub TaskGridView_RowCancelingEdit()
    'Reset the edit index.
    TaskGridView.EditIndex = -1
    'Bind data to the GridView control.
    BindData()
  End Sub

  Protected Sub TaskGridView_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
    'Retrieve the table from the session object.
    Dim dt = CType(Session("TaskTable"), DataTable)

    'Update the values.
    Dim row = TaskGridView.Rows(e.RowIndex)
    dt.Rows(row.DataItemIndex)("Id") = (CType((row.Cells(1).Controls(0)), TextBox)).Text
    dt.Rows(row.DataItemIndex)("Description") = (CType((row.Cells(2).Controls(0)), TextBox)).Text
    dt.Rows(row.DataItemIndex)("IsComplete") = (CType((row.Cells(3).Controls(0)), CheckBox)).Checked

    'Reset the edit index.
    TaskGridView.EditIndex = -1

    'Bind data to the GridView control.
    BindData()
  End Sub

  Private Sub BindData()
    TaskGridView.DataSource = Session("TaskTable")
    TaskGridView.DataBind()
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title>GridView example</title>
</head>
<body>
    <form id="form1" runat="server">
    <div>
    
      <asp:GridView ID="TaskGridView" runat="server" 
        AutoGenerateEditButton="True" 
        AllowPaging="true"
        OnRowEditing="TaskGridView_RowEditing"         
        OnRowCancelingEdit="TaskGridView_RowCancelingEdit" 
        OnRowUpdating="TaskGridView_RowUpdating"
        OnPageIndexChanging="TaskGridView_PageIndexChanging">
      </asp:GridView>
    
    </div>
    </form>
</body>
</html>

Uwagi

RowCancelingEditZdarzenie jest zgłaszane, gdy kliknięto przycisk Anuluj wiersza w trybie edycji, ale przed opuszczeniem wiersza w trybie edycji.The RowCancelingEdit event is raised when the Cancel button of a row in edit mode is clicked, but before the row exits edit mode. Dzięki temu można podać metodę obsługi zdarzeń, która wykonuje procedurę niestandardową, taką jak zatrzymanie operacji anulowania, jeśli w przypadku wystąpienia tego zdarzenia zostanie umieszczony wiersz w stanie niepożądanym.This enables you to provide an event-handling method that performs a custom routine, such as stopping the cancel operation if it would put the row in an undesired state, whenever this event occurs.

GridViewCancelEditEventArgsObiekt jest przesyłany do metody obsługi zdarzeń, co pozwala ustalić indeks bieżącego wiersza i wskazywać, że operacja anulowania powinna zostać zatrzymana.A GridViewCancelEditEventArgs object is passed to the event-handling method, which enables you to determine the index of the current row and to indicate that the cancel operation should be stopped. Aby zatrzymać operację anulowania, ustaw Cancel Właściwość GridViewCancelEditEventArgs obiektu na true .To stop the cancel operation, set the Cancel property of the GridViewCancelEditEventArgs object to true.

Aby uzyskać więcej informacji o sposobie obsługi zdarzeń, zobacz Obsługa iwywoływanie zdarzeń.For more information about how to handle events, see Handling and Raising Events.

Dotyczy

Zobacz też