DetailsViewUpdatedEventHandler 委托

  • 参考

定义

命名空间:
System.Web.UI.WebControls
程序集:
System.Web.dll

表示处理 ItemUpdated 控件的 DetailsView 事件的方法。 此类不能被继承。

public delegate void DetailsViewUpdatedEventHandler(System::Object ^ sender, DetailsViewUpdatedEventArgs ^ e);
public delegate void DetailsViewUpdatedEventHandler(object sender, DetailsViewUpdatedEventArgs e);
type DetailsViewUpdatedEventHandler = delegate of obj * DetailsViewUpdatedEventArgs -> unit
Public Delegate Sub DetailsViewUpdatedEventHandler(sender As Object, e As DetailsViewUpdatedEventArgs)

参数

sender
Object

事件源。

e
DetailsViewUpdatedEventArgs

包含事件数据的 DetailsViewUpdatedEventArgs。

示例

下面的代码示例演示如何以编程方式将委托添加到DetailsViewUpdatedEventHandlerItemUpdated控件的事件DetailsView。


<%@ 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 Page_Load(Object sender, EventArgs e)
  {

    // Create a new DetailsView object.
    DetailsView customerDetailsView = new DetailsView();

    // Set the DetailsView object's properties.
    customerDetailsView.ID = "CustomerDetailsView";
    customerDetailsView.DataSourceID = "DetailsViewSource";
    customerDetailsView.AutoGenerateRows = true;
    customerDetailsView.AutoGenerateEditButton = true;
    customerDetailsView.AllowPaging = true;
    customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };
    customerDetailsView.PagerSettings.Position = PagerPosition.Bottom;

    // Programmatically register the event-handling methods
    // for the DetailsView control.
    customerDetailsView.ItemUpdated += new DetailsViewUpdatedEventHandler(this.CustomerDetailsView_ItemUpdated);
        
    // Add the DetailsView object to the Controls collection
    // of the PlaceHolder control.
    DetailsViewPlaceHolder.Controls.Add(customerDetailsView);

  }  
  
  void CustomerDetailsView_ItemUpdated(Object sender, 
    DetailsViewUpdatedEventArgs e)
  {
    // Use the Exception property to determine whether an exception
    // occurred during the insert operation.
    if (e.Exception == null)
    {
      // Use the Values property to get the value entered by 
      // the user for the CompanyName field.
      String keyFieldValue = e.Keys["CustomerID"].ToString();

      // Display a confirmation message.
      MessageLabel.Text = "Record " + keyFieldValue + 
        " updated successfully. ";

      // Display the old and new values.
      DisplayValues(e);

      if (e.AffectedRows == 1)
      {
        MessageLabel.Text += e.AffectedRows.ToString() + 
          " record updated.";
      }
      else
      {
        MessageLabel.Text += e.AffectedRows.ToString() + 
          " records updated.";
      }
    }
    else
    {
      // Insert the code to handle the exception.
      MessageLabel.Text = e.Exception.Message;

      // Use the ExceptionHandled property to indicate that the 
      // exception is already handled.
      e.ExceptionHandled = true;

      // When an exception occurs, keep the DetailsView
      // control in edit mode.
      e.KeepInEditMode = true;
    }
  }

  void DisplayValues(DetailsViewUpdatedEventArgs e)
  {
    
    MessageLabel.Text += "<br/></br>";
    
    // Iterate through the OldValue and NewValues
    // properties and display the values.
    for (int i = 0; i < e.OldValues.Count; i++)
    {
      MessageLabel.Text += "Old Value=" + e.OldValues[i].ToString() +
        ", New Value=" + e.NewValues[i].ToString() + "<br/>";
    }

    MessageLabel.Text += "</br>";
    
  }
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewUpdatedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewUpdatedEventHandler Example</h3>
        
      <!-- Use a PlaceHolder control as the container for the -->
      <!-- dynamically generated DetailsView control.         -->       
      <asp:PlaceHolder id="DetailsViewPlaceHolder"
        runat="server"/>
        
      <br/><br/>
      
      <asp:label id="MessageLabel"
        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]"
        updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          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 Page_Load(sender As Object, e as EventArgs)

    ' Create a new DetailsView object.
    Dim customerDetailsView As New DetailsView()

    ' Set the DetailsView object's properties.
    customerDetailsView.ID = "CustomerDetailsView"
    customerDetailsView.DataSourceID = "DetailsViewSource"
    customerDetailsView.AutoGenerateRows = True
    customerDetailsView.AutoGenerateEditButton = True
    customerDetailsView.AllowPaging = True
    customerDetailsView.PagerSettings.Position = PagerPosition.Bottom

    Dim keyArray() As String = {"CustomerID"}
    customerDetailsView.DataKeyNames = keyArray
    
    ' Programmatically register the event-handling methods
    ' for the DetailsView control.
    AddHandler customerDetailsView.ItemUpdated, _
      AddressOf CustomerDetailsView_ItemUpdated
        
    ' Add the DetailsView object to the Controls collection
    ' of the PlaceHolder control.
    DetailsViewPlaceHolder.Controls.Add(customerDetailsView)

  End Sub
  
  Sub CustomerDetailsView_ItemUpdated(ByVal sender As Object, _
    ByVal e As DetailsViewUpdatedEventArgs)
  
    ' Use the Exception property to determine whether an exception
    ' occurred during the insert operation.
    If e.Exception Is Nothing Then
    
      ' Use the Values property to get the value entered by 
      ' the user for the CompanyName field.
      Dim keyFieldValue As String = e.Keys("CustomerID").ToString()

      ' Display a confirmation message.
      MessageLabel.Text = "Record " & keyFieldValue & _
        " updated successfully. "

      ' Display the old and new values.
      DisplayValues(e)

      If e.AffectedRows = 1 Then

        MessageLabel.Text &= e.AffectedRows.ToString() & _
          " record updated."
      
      Else
      
        MessageLabel.Text &= e.AffectedRows.ToString() & _
          " records updated."
      
      End If
    
    Else
    
      ' Insert the code to handle the exception.
      MessageLabel.Text = e.Exception.Message

      ' Use the ExceptionHandled property to indicate that the 
      ' exception is already handled.
      e.ExceptionHandled = True

      ' When an exception occurs, keep the DetailsView
      ' control in edit mode.
      e.KeepInEditMode = True
    
    End If
    
  End Sub

  Sub DisplayValues(ByVal e As DetailsViewUpdatedEventArgs)
    
    MessageLabel.Text &= "<br/></br>"
    
    ' Iterate through the OldValue and NewValues
    ' properties and display the values.
    Dim i As Integer
        
    For i = 0 To e.OldValues.Count - 1
    
      MessageLabel.Text &= "Old Value=" & e.OldValues(i).ToString() & _
        ", New Value=" & e.NewValues(i).ToString() & "<br/>"
    
    Next

    MessageLabel.Text &= "</br>"
    
  End Sub
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewUpdatedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewUpdatedEventHandler Example</h3>
        
      <!-- Use a PlaceHolder control as the container for the -->
      <!-- dynamically generated DetailsView control.         -->       
      <asp:PlaceHolder id="DetailsViewPlaceHolder"
        runat="server"/>
        
      <br/><br/>
      
      <asp:label id="MessageLabel"
        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]"
        updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          Where [CustomerID]=@CustomerID"
        connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

下面的代码示例演示如何以声明方式将委托添加到DetailsViewUpdatedEventHandlerItemUpdated控件的事件DetailsView。


<%@ 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 CustomerDetailsView_ItemUpdated(Object sender, 
    DetailsViewUpdatedEventArgs e)
  {
    // Use the Exception property to determine whether an exception
    // occurred during the insert operation.
    if (e.Exception == null)
    {
      // Use the Values property to get the value entered by 
      // the user for the CompanyName field.
      String keyFieldValue = e.Keys["CustomerID"].ToString();

      // Display a confirmation message.
      MessageLabel.Text = "Record " + keyFieldValue + 
        " updated successfully. ";

      // Display the old and new values.
      DisplayValues(e);

      if (e.AffectedRows == 1)
      {
        MessageLabel.Text += e.AffectedRows.ToString() + 
          " record updated.";
      }
      else
      {
        MessageLabel.Text += e.AffectedRows.ToString() + 
          " records updated.";
      }
    }
    else
    {
      // Insert the code to handle the exception.
      MessageLabel.Text = e.Exception.Message;

      // Use the ExceptionHandled property to indicate that the 
      // exception is already handled.
      e.ExceptionHandled = true;

      // When an exception occurs, keep the DetailsView
      // control in edit mode.
      e.KeepInEditMode = true;
    }
  }

  void DisplayValues(DetailsViewUpdatedEventArgs e)
  {
    
    MessageLabel.Text += "<br/></br>";
    
    // Iterate through the OldValue and NewValues
    // properties and display the values.
    for (int i = 0; i < e.OldValues.Count; i++)
    {
      MessageLabel.Text += "Old Value=" + e.OldValues[i].ToString() +
        ", New Value=" + e.NewValues[i].ToString() + "<br/>";
    }

    MessageLabel.Text += "</br>";
    
  }
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewUpdatedEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewUpdatedEventHandler Example</h3>
                       
      <asp:detailsview id="CustomerDetailsView"
        datasourceid="DetailsViewSource"
        autogeneraterows="true"
        autogenerateeditbutton="true"  
        allowpaging="true"
        datakeynames="CustomerID" 
        onitemupdated="CustomerDetailsView_ItemUpdated"
        runat="server">
          
        <pagersettings position="Bottom"/> 
                  
      </asp:detailsview>
      
      <br/>
      
      <asp:label id="MessageLabel"
        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]"
        updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          Where [CustomerID]=@CustomerID"
        connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>


<%@ Page language="VB" autoeventwireup="false" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<script runat="server">
  
  Sub CustomerDetailsView_ItemUpdated(ByVal sender As Object, ByVal e As DetailsViewUpdatedEventArgs) Handles CustomerDetailsView.ItemUpdated
  
    ' Use the Exception property to determine whether an exception
    ' occurred during the insert operation.
    If e.Exception Is Nothing Then
    
      ' Use the Values property to get the value entered by 
      ' the user for the CompanyName field.
      Dim keyFieldValue As String = e.Keys("CustomerID").ToString()

      ' Display a confirmation message.
      MessageLabel.Text = "Record " & keyFieldValue & _
        " updated successfully. "

      ' Display the old and new values.
      DisplayValues(e)

      If e.AffectedRows = 1 Then

        MessageLabel.Text &= e.AffectedRows.ToString() & _
          " record updated."
      
      Else
      
        MessageLabel.Text &= e.AffectedRows.ToString() & _
          " records updated."
      
      End If
    
    Else
    
      ' Insert the code to handle the exception.
      MessageLabel.Text = e.Exception.Message

      ' Use the ExceptionHandled property to indicate that the 
      ' exception is already handled.
      e.ExceptionHandled = True

      ' When an exception occurs, keep the DetailsView
      ' control in edit mode.
      e.KeepInEditMode = True
    
    End If
    
  End Sub

  Sub DisplayValues(ByVal e As DetailsViewUpdatedEventArgs)
    
    MessageLabel.Text &= "<br/></br>"
    
    ' Iterate through the OldValue and NewValues
    ' properties and display the values.
    Dim i As Integer
        
    For i = 0 To e.OldValues.Count - 1
    
      MessageLabel.Text &= "Old Value=" & e.OldValues(i).ToString() & _
        ", New Value=" & e.NewValues(i).ToString() & "<br/>"
    
    Next

    MessageLabel.Text &= "</br>"
    
  End Sub
  
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewUpdatedEvent Handler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewUpdatedEvent Handler Example</h3>
                       
      <asp:detailsview id="CustomerDetailsView"
        datasourceid="DetailsViewSource"
        autogeneraterows="true"
        autogenerateeditbutton="true"  
        allowpaging="true"
        datakeynames="CustomerID" 
        runat="server">
          
        <pagersettings position="Bottom"/> 
                  
      </asp:detailsview>
      
      <br/>
      
      <asp:label id="MessageLabel"
        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]"
        updatecommand="Update [Customers] Set 
          [CompanyName]=@CompanyName, [Address]=@Address, 
          [City]=@City, [PostalCode]=@PostalCode, 
          [Country]=@Country 
          Where [CustomerID]=@CustomerID"
        connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
          
    </form>
  </body>
</html>

注解

DetailsView当“更新”按钮 (CommandName按钮的属性设置为“更新”时，控件将引发 ItemUpdated 事件) 控件内的单击，但在控件更新记录之后DetailsView。 这允许你提供一个事件处理程序，每当发生此事件时执行自定义例程，例如检查更新操作的结果。

创建 DetailsViewUpdatedEventHandler 委托时，需要标识将处理该事件的方法。 若要将事件与事件处理程序关联，请将该委托的一个实例添加到事件中。 除非移除了该委托，否则每当发生该事件时就会调用事件处理程序。 有关事件处理程序委托的详细信息，请参阅 处理和引发事件。

扩展方法

GetMethodInfo(Delegate)

获取指示指定委托表示的方法的对象。

适用于

另请参阅