GridView.RowUpdating Ereignis

Definition

Tritt ein, wenn auf die Schaltfläche Aktualisieren einer Zeile geklickt wird, allerdings bevor das GridView-Steuerelement die Zeile tatsächlich aktualisiert.Occurs when a row's Update button is clicked, but before the GridView control updates the row.

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

Beispiele

Im folgenden Beispiel wird veranschaulicht, wie das RowUpdating -Ereignis verwendet wird, um die Werte im Datenquellen Objekt zu aktualisieren, wenn die Datenquelle Programm gesteuert festgelegt wird.The following example demonstrates how to use the RowUpdating event to update the values in the data source object 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>

Hinweise

Das RowUpdating -Ereignis wird ausgelöst, wenn auf die Schaltfläche Aktualisieren einer Zeile geklickt wird GridView , jedoch bevor das-Steuerelement die Zeile aktualisiert.The RowUpdating event is raised when a row's Update button is clicked, but before the GridView control updates the row. Dies ermöglicht es Ihnen, eine Ereignis Behandlungsmethode bereitzustellen, die eine benutzerdefinierte Routine ausführt, z. b. den Aktualisierungs Vorgang bei jedem Auftreten dieses Ereignisses.This enables you to provide an event-handling method that performs a custom routine, such as canceling the update operation, whenever this event occurs.

Ein GridViewUpdateEventArgs -Objekt wird an die Ereignis Behandlungsmethode, die es Ihnen ermöglicht, den Index der aktuellen Zeile zu bestimmen und anzugeben, dass der Aktualisierungs Vorgang abgebrochen werden soll.A GridViewUpdateEventArgs object is passed to the event-handling method, which enables you to determine the index of the current row and to indicate that the update operation should be canceled. Um den Aktualisierungs Vorgang abzubrechen, Cancel legen Sie die GridViewUpdateEventArgs -Eigenschaft truedes-Objekts auf fest.To cancel the update operation, set the Cancel property of the GridViewUpdateEventArgs object to true. Sie können ggf. Keysauch OldValuesdie Auflistungen, und NewValues bearbeiten, bevor die Werte an die Datenquelle übermittelt werden.You can also manipulate the Keys, OldValues, and NewValues collections, if necessary, before the values are passed to the data source. Eine gängige Methode, diese Auflistungen zu verwenden, besteht darin, die vom Benutzer bereitgestellten Werte in HTML zu codieren, bevor Sie in der Datenquelle gespeichert werden.A common way to use these collections is to HTML-encode the values supplied by the user before they are stored in the data source. Dies trägt dazu bei, Skript Injection-Angriffe zu verhindern.This helps to prevent script injection attacks.

Hinweis

Die Keys- OldValues Auflistung und die-Auflistung werden nur dann GridView automatisch aufgefüllt, wenn das- NewValues Steuerelement DataSourceID mithilfe der-Eigenschaft an Daten gebunden ist.The Keys, OldValues and NewValues collections are automatically populated only when the GridView control is bound to data by using the DataSourceID property.

Weitere Informationen zum Behandeln von Ereignissen finden Sie unter behandeln und Auslösen von Ereignissen.For more information about how to handle events, see Handling and Raising Events.

Gilt für:

Siehe auch