GridViewDeleteEventArgs.Keys Propriété

Définition

Obtient un dictionnaire des paires nom-valeur du champ qui représentent la clé primaire de la ligne à supprimer.

public:
 property System::Collections::Specialized::IOrderedDictionary ^ Keys { System::Collections::Specialized::IOrderedDictionary ^ get(); };
public System.Collections.Specialized.IOrderedDictionary Keys { get; }
member this.Keys : System.Collections.Specialized.IOrderedDictionary
Public ReadOnly Property Keys As IOrderedDictionary

Valeur de propriété

IOrderedDictionary

Dictionnaire qui contient les paires nom-valeur de champ qui représentent la clé primaire de la ligne à supprimer.

Exemples

L’exemple suivant montre comment utiliser la Values propriété pour obtenir les valeurs des champs clés de la ligne à supprimer. Les valeurs sont ensuite écrites dans un fichier journal d’enregistrements supprimés.


<%@ Page language="C#" %>
<%@ import namespace="System.IO" %>

<!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_RowDeleting(Object sender, GridViewDeleteEventArgs e)
  {

    // Record the delete operation in a log file.

    // Create the log text. 
    String logText = "";

    // Append the values of the key fields to the log text.
    foreach (DictionaryEntry keyEntry in e.Keys)
    {
      logText += keyEntry.Key + "=" + keyEntry.Value + ";";
    }

    // Append the values of the non-key fields to the log text.
    foreach (DictionaryEntry valueEntry in e.Values)
    {
      logText += valueEntry.Key + "=" + valueEntry.Value + ";";
    }

    // Display the log content.
    LogTextLabel.Text = logText;
    
    // Append the text to a log file.
    try
    {
      StreamWriter sw;
      sw = File.AppendText(Server.MapPath(null) + "\\deletelog.txt");
      sw.WriteLine(logText);
      sw.Flush();
      sw.Close();
    }
    catch(UnauthorizedAccessException ex)
    {
      // You must provide read/write access to the file using ACLs.
      LogErrorLabel.Text = "You do not have permission to write to the log.";
    }

  }
    
  void CustomersGridView_RowDeleted(Object sender, GridViewDeletedEventArgs e)
  {
    
    if (e.Exception == null)
    {
      // The delete operation succeeded. Clear the message label.
      Message.Text = "";
    }
    else
    {
      // The delete operation failed. Display an error message.
      Message.Text = e.AffectedRows.ToString() + " rows deleted. " + e.Exception.Message;
      e.ExceptionHandled = true;
    }
        
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewDeleteEventArgs Keys and Values Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewDeleteEventArgs Keys and Values Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
        
      <br/>
      
      <asp:label id="LogTextLabel"
        forecolor="Red"          
        runat="server"/>
        
      <br/>
        
      <asp:label id="LogErrorLabel"
        forecolor="Red"          
        runat="server"/>
                
      <br/>

      <asp:gridview id="CustomersGridView" 
        allowpaging="true"
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogeneratedeletebutton="true" 
        datakeynames="CustomerID"
        onrowdeleted="CustomersGridView_RowDeleted"
        onrowdeleting="CustomersGridView_RowDeleting"   
        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]"
        deletecommand="Delete from Customers where CustomerID = @CustomerID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

<%@ Page language="VB" %>
<%@ import namespace="System.IO" %>

<!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_RowDeleting(ByVal sender As Object, ByVal e As GridViewDeleteEventArgs)

    ' Record the delete operation in a log file.

    ' Create the log text. 
    Dim logText As String = ""

    ' Append the values of the key fields to the log text.
    Dim i As Integer
    For i = 0 To e.Keys.Count - 1
    
      logText &= e.Keys(i).ToString() & ";"
      
    Next

    ' Append the values of the non-key fields to the log text.
    For i = 0 To e.Values.Count - 1
    
      If e.Values(i) IsNot Nothing Then
        logText &= e.Values(i).ToString() & ";"
      Else
        logText &= "Nothing" & ";"
      End If
      
    Next
    
    ' Display the log content.
    LogTextLabel.Text = logText

    ' Append the text to a log file.
    Try
    
      Dim sw As StreamWriter
      sw = File.AppendText(Server.MapPath(Nothing) & "\deletelog.txt")
      sw.WriteLine(logText)
      sw.Flush()
      sw.Close()
    
    Catch ex As UnauthorizedAccessException
    
      ' You must provide read/write access to the file using ACLs.
      LogErrorLabel.Text = "You do not have permission to write to the log."
    
    End Try

  End Sub
    
  Sub CustomersGridView_RowDeleted(ByVal sender As Object, ByVal e As GridViewDeletedEventArgs)
    
    If e.Exception Is Nothing Then
    
      ' The delete operation succeeded. Clear the message label.
      Message.Text = ""
    
    Else
    
      ' The delete operation failed. Display an error message.
      Message.Text = e.AffectedRows.ToString() & " rows deleted. " & e.Exception.Message
      e.ExceptionHandled = True
      
    End If
        
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridViewDeleteEventArgs Keys and Values Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridViewDeleteEventArgs Keys and Values Example</h3>
            
      <asp:label id="Message"
        forecolor="Red"          
        runat="server"/>
        
      <br/>
      
      <asp:label id="LogTextLabel"
        forecolor="Red"          
        runat="server"/>
        
      <br/>
        
      <asp:label id="LogErrorLabel"
        forecolor="Red"          
        runat="server"/>
                
      <br/>

      <asp:gridview id="CustomersGridView" 
        allowpaging="true"
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogeneratedeletebutton="true" 
        datakeynames="CustomerID"
        onrowdeleted="CustomersGridView_RowDeleted"
        onrowdeleting="CustomersGridView_RowDeleting"   
        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]"
        deletecommand="Delete from Customers where CustomerID = @CustomerID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

Remarques

Lorsque la DataKeyNames propriété d’un GridView contrôle est définie, utilisez la Keys propriété (dictionnaire) pour obtenir la valeur de la clé primaire ou des clés de la ligne à supprimer.

Notes

Pour obtenir les valeurs des champs non clés, utilisez la Values propriété.

Le Keys dictionnaire est automatiquement rempli avec les paires nom/valeur du champ ou des champs spécifiés dans la DataKeyNames propriété. Si plusieurs champs forment la clé primaire, une entrée distincte est ajoutée au Keys dictionnaire pour chaque champ de clé.

Pour déterminer le nom d’un champ de clé, utilisez la DictionaryEntry.Key propriété d’un System.Collections.DictionaryEntry objet dans le Keys dictionnaire. Pour déterminer la valeur d’un champ de clé, utilisez la DictionaryEntry.Value propriété.

S’applique à

Voir aussi