FormViewDeletedEventArgs.Values 属性

定义

获取包含已删除记录所对应的非键字段名称/值对的字典。Gets a dictionary of the non-key field name/value pairs for the deleted record.

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

属性值

一个含有字典的 OrderedDictionary 对象,其中包含已删除记录所对应的非键字段名称/值对。An OrderedDictionary that contains a dictionary of the non-key field name/value pairs for the deleted record.

示例

下面的示例演示如何使用Values属性访问已删除记录的非键字段的值。The following example demonstrates how to use the Values property to access the values of the non-key fields for a deleted record.


<%@ 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 EmployeeFormView_ItemDeleted(Object sender, FormViewDeletedEventArgs e)
  {
    // Display the values 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 values 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>FormViewDeletedEventArgs Keys and Values Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>FormViewDeletedEventArgs Keys and Values Example</h3>
                       
      <asp:formview id="EmployeeFormView"
        datasourceid="EmployeeSource"
        allowpaging="true"
        datakeynames="EmployeeID"
        onitemdeleted="EmployeeFormView_ItemDeleted"  
        runat="server">
        
        <itemtemplate>
        
          <table>
            <tr>
              <td>
                <asp:image id="EmployeeImage"
                  imageurl='<%# Eval("PhotoPath") %>'
                  alternatetext='<%# Eval("LastName") %>' 
                  runat="server"/>
              </td>
              <td>
                <asp:label id="FirstNameLabel"
                  text='<%#Bind("FirstName")%>'
                  font-bold="true"
                  runat="server"/>
                <asp:label id="LastNameLabel"
                  text='<%#Bind("LastName")%>'
                  font-bold="true"
                  runat="server"/>
                <br/>     
                <asp:label id="TitleLabel"
                  text='<%#Bind("Title")%>'
                  runat="server"/>        
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:button id="DeleteButton"
                  text="Delete Record"
                  commandname="Delete"
                  runat="server" />
              </td>
            </tr>
          </table>
        
        </itemtemplate>         
                  
      </asp:formview>
      
      <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="EmployeeSource"
        selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
        deletecommand="Delete [Employees] Where [EmployeeID]=@EmployeeID"
        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 EmployeeFormView_ItemDeleted(ByVal sender As Object, ByVal e As FormViewDeletedEventArgs) Handles EmployeeFormView.ItemDeleted
  
    Dim entry As DictionaryEntry
    
    ' Display the values of the key fields in the Keys property.
    KeysMessageLabel.Text = _
      "The key fields for the deleted record are: <br/>"

    ' In Visual Basic, 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 values 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>FormViewDeletedEventArgs Keys and Values Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>FormViewDeletedEventArgs Keys and Values Example</h3>
                       
      <asp:formview id="EmployeeFormView"
        datasourceid="EmployeeSource"
        allowpaging="true"
        datakeynames="EmployeeID"
        runat="server">
        
        <itemtemplate>
        
          <table>
            <tr>
              <td>
                <asp:image id="EmployeeImage"
                  imageurl='<%# Eval("PhotoPath") %>'
                  alternatetext='<%# Eval("LastName") %>' 
                  runat="server"/>
              </td>
              <td>
                <asp:label id="FirstNameLabel"
                  text='<%#Bind("FirstName")%>'
                  font-bold="true"
                  runat="server"/>
                <asp:label id="LastNameLabel"
                  text='<%#Bind("LastName")%>'
                  font-bold="true"
                  runat="server"/>
                <br/>     
                <asp:label id="TitleLabel"
                  text='<%#Bind("Title")%>'
                  runat="server"/>        
              </td>
            </tr>
            <tr>
              <td colspan="2">
                <asp:button id="DeleteButton"
                  text="Delete Record"
                  commandname="Delete"
                  runat="server" />
              </td>
            </tr>
          </table>
        
        </itemtemplate>         
                  
      </asp:formview>
      
      <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="EmployeeSource"
        selectcommand="Select [EmployeeID], [LastName], [FirstName], [Title], [PhotoPath] From [Employees]"
        deletecommand="Delete [Employees] Where [EmployeeID]=@EmployeeID"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

注解

Values使用属性可访问已删除记录的非键字段的值。Use the Values property to access the values of the non-key fields for a deleted record. 例如, 您可以使用这些值来记录已删除的记录。For example, you can use these values to keep a log of deleted records.

备注

Values当在项模板中使用双向绑定表达式时, 才填充属性。The Values property is populated only when two-way binding expressions are used in the item template. 有关双向绑定表达式的详细信息, 请参阅绑定到数据库For more information on two-way binding expressions, see Binding to Databases.

属性返回实现System.Collections.Specialized.IOrderedDictionary接口的对象。OrderedDictionary ValuesThe Values property returns an OrderedDictionary object that implements the System.Collections.Specialized.IOrderedDictionary interface. OrderedDictionary对象包含System.Collections.DictionaryEntry对象, 这些对象表示已删除记录的非键字段。The OrderedDictionary object contains System.Collections.DictionaryEntry objects that represent the non-key fields of the deleted record. 若要访问字段名称, 请使用Keys OrderedDictionary对象的属性。To access the field names, use the Keys property of the OrderedDictionary object. 同样, 可以使用Values属性访问字段值。Similarly, you can access the field values by using the Values property.

备注

作为快捷方式, 还可以使用OrderedDictionary对象的索引器来访问字段值。As a shortcut, you can also use the indexer of the OrderedDictionary object to access the field values. 使用索引器的优点是它直接返回字段值。The advantage in using the indexer is that it returns field values directly. 依赖于字段顺序的数据源控件 (如AccessDataSource) 只能通过索引访问字段值。Data source controls that rely on the field order (such as AccessDataSource) can access field values only by index.

此属性不包含已删除记录的键字段 (由DataKeyNames属性指定)。This property does not contain the key fields (as specified by the DataKeyNames property) for the deleted record. 若要访问密钥字段, 请使用Keys属性。To access the key fields, use the Keys property.

适用于

另请参阅