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DetailsViewDeletedEventArgs.Keys Właściwość

Definicja

Pobiera uporządkowany słownik par nazwa/wartość pola klucza, który zawiera nazwy i wartości pól klucza usuniętych elementów.

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

Wartość właściwości

IOrderedDictionary

Element IOrderedDictionary zawierający uporządkowany słownik par nazwa/wartość pola klucza używany do dopasowania elementu do usunięcia.

Przykłady

W poniższym przykładzie kodu pokazano, jak za pomocą Keys właściwości uzyskać dostęp do wartości pól klucza dla usuniętego rekordu.


<%@ 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 StoresDetailView_ItemDeleted(Object sender, 
  DetailsViewDeletedEventArgs e)
  {
    // Display the value of the key fields in the Keys property.
    KeysMessageLabel.Text =
      "The key fields for the deleted record are: <br/>";

    foreach (DictionaryEntry entry in e.Keys)
    {
      DisplayValue(entry, KeysMessageLabel);
    }

    // Display the value of the non-key fields in the Values 
    // property.
    ValuesMessageLabel.Text =
      "The non-key fields for the deleted record are: <br/>";
    
    foreach (DictionaryEntry entry in e.Values)
    {
      DisplayValue(entry, ValuesMessageLabel);
    }
  }

  void DisplayValue(DictionaryEntry entry, Label displayLabel)
  {
    // Display the field name contained in the DictionaryEntry object.
    if (entry.Key != null)
    {
      displayLabel.Text += "Name=" + entry.Key.ToString() + ", ";
    }
    else
    {
      displayLabel.Text += "Name=null, ";
    }

    // Display the field value contained in the DictionaryEntry object.
    if (entry.Value != null)
    {
      displayLabel.Text += "Value=" + entry.Value.ToString() + "<br/>";
    }
    else
    {
      displayLabel.Text += "Value=null<br/>";
    }
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewDeletedEventArgs Keys and Values Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewDeletedEventArgs Keys and Values Example</h3>
                
        <asp:detailsview id="CustomerDetailsView"
          datasourceid="DetailsViewSource"
          datakeynames="CustomerID"
          autogeneratedeletebutton="true"  
          autogeneraterows="true"
          allowpaging="true"
          onitemdeleted="StoresDetailView_ItemDeleted" 
          runat="server">
               
          <fieldheaderstyle backcolor="Navy"
            forecolor="White"/>
                    
        </asp:detailsview>
        
        <asp:label id="KeysMessageLabel"
          forecolor="Red"
          runat="server"/>
          
        <br/><br/>
          
        <asp:label id="ValuesMessageLabel"
          forecolor="Red"
          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="DetailsViewSource"
          selectcommand="Select [CustomerID], [CompanyName], [Address], 
            [City], [PostalCode], [Country] From [Customers]"
          deletecommand="Delete [Customers] 
            Where [CustomerID]=@CustomerID"
          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 StoresDetailView_ItemDeleted(ByVal sender As Object, _
    ByVal e As DetailsViewDeletedEventArgs)

    Dim entry As DictionaryEntry
    Dim i As Integer
    
    ' Display the value of the key fields in the Keys property.
    KeysMessageLabel.Text = _
      "The key fields for the deleted record are: <br/>"

    ' In VB, you cannot iterate through the DictionaryEntry objects
    ' in the Keys property directly. Use the CopyTo method to 
    ' copy the objects to an array first.
    Dim keysArray(e.Keys.Count - 1) As DictionaryEntry
    e.Keys.CopyTo(keysArray, 0)
    
    ' Iterate through the array and display its values.
    For Each entry In keysArray
    
      DisplayValue(entry, KeysMessageLabel)
    
    Next

    ' Display the value of the non-key fields in the Values 
    ' property.
    ValuesMessageLabel.Text = _
      "The non-key fields for the deleted record are: <br/>"

    Dim valuesArray(e.Values.Count - 1) As DictionaryEntry
    e.Values.CopyTo(valuesArray, 0)

    For Each entry In valuesArray
    
      DisplayValue(entry, ValuesMessageLabel)
    
    Next
    
  End Sub

  Sub DisplayValue(ByVal entry As DictionaryEntry, _
    ByVal displayLabel As Label)
  
    ' Display the field name contained in the DictionaryEntry object.
    If entry.Key IsNot Nothing Then
    
      displayLabel.Text &= "Name=" & entry.Key.ToString() & ", "
    
    Else
    
      displayLabel.Text &= "Name=null, "
      
    End If

    ' Display the field value contained in the DictionaryEntry object.
    If entry.Value IsNot Nothing Then
    
      displayLabel.Text &= "Value=" & entry.Value.ToString() & "<br/>"
    
    Else
    
      displayLabel.Text &= "Value=null<br/>"
      
    End If
        
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewDeletedEventArgs Keys and Values Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewDeletedEventArgs Keys and Values Example</h3>
                
        <asp:detailsview id="CustomerDetailsView"
          datasourceid="DetailsViewSource"
          datakeynames="CustomerID"
          autogeneratedeletebutton="true"  
          autogeneraterows="true"
          allowpaging="true"
          onitemdeleted="StoresDetailView_ItemDeleted" 
          runat="server">
               
          <fieldheaderstyle backcolor="Navy"
            forecolor="White"/>
                    
        </asp:detailsview>
        
        <asp:label id="KeysMessageLabel"
          forecolor="Red"
          runat="server"/>
          
        <br/><br/>
          
        <asp:label id="ValuesMessageLabel"
          forecolor="Red"
          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="DetailsViewSource"
          selectcommand="Select [CustomerID], [CompanyName], [Address], 
            [City], [PostalCode], [Country] From [Customers]"
          deletecommand="Delete [Customers] 
            Where [CustomerID]=@CustomerID"
          connectionstring=
            "<%$ ConnectionStrings:NorthWindConnectionString%>" 
         runat="server"/>
            
      </form>
  </body>
</html>

Uwagi

Keys Użyj właściwości , aby uzyskać dostęp do wartości pól klucza rekordu do usunięcia. Możesz na przykład użyć tych wartości, aby zachować dziennik usuniętych rekordów.

Uwaga

Ta właściwość zawiera tylko pola klucza. Aby uzyskać dostęp do pól innych niż klucz, użyj Values właściwości .

Właściwość Keys zwraca obiekt implementujący IOrderedDictionary interfejs. Obiekt zawiera DictionaryEntry obiekty reprezentujące pola klucza rekordu do usunięcia.

Uwaga

Skrót umożliwia również bezpośredni dostęp do wartości pól za pomocą indeksatora IOrderedDictionary obiektu.

Dotyczy

Zobacz też