DetailsViewInsertEventHandler Делегат

Определение

Пространство имен:: System.Web.UI.WebControls

Сборка:: System.Web.dll

Важно!

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Представляет метод, обрабатывающий ItemInserting событие DetailsView элемента управления.

public delegate void DetailsViewInsertEventHandler(System::Object ^ sender, DetailsViewInsertEventArgs ^ e);

public delegate void DetailsViewInsertEventHandler(object sender, DetailsViewInsertEventArgs e);

type DetailsViewInsertEventHandler = delegate of obj * DetailsViewInsertEventArgs -> unit

Public Delegate Sub DetailsViewInsertEventHandler(sender As Object, e As DetailsViewInsertEventArgs)

Параметры

sender: Object

Источник события.

e: DetailsViewInsertEventArgs

Объект, DetailsViewInsertEventArgs содержащий данные события.

Примеры

В следующем примере кода показано, как программно добавить DetailsViewInsertEventHandler делегат в ItemInserting событие DetailsView элемента управления.


<%@ 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.AutoGenerateInsertButton = true;
    customerDetailsView.AllowPaging = true;
    customerDetailsView.DataKeyNames = new String[1] { "CustomerID" };
    
    // Programmatically register the event-handling method
    // for the ItemInserted event of a DetailsView control.
    customerDetailsView.ItemInserting += new DetailsViewInsertEventHandler(this.CustomerDetailsView_ItemInserting);

    // Add the DetailsView object to the Controls collection
    // of the PlaceHolder control.
    DetailsViewPlaceHolder.Controls.Add(customerDetailsView);

  }

  void CustomerDetailsView_ItemInserting(Object sender, DetailsViewInsertEventArgs e)
  {
    // Use the Values property to retrieve the key field value.
    String keyValue = e.Values["CustomerID"].ToString();

    // Insert the record only if the key field is four characters
    // long; otherwise, cancel the insert operation.
    if (keyValue.Length == 4)
    {
      // Change the key field value to upper case before inserting 
      // the record in the data source.
      e.Values["CustomerID"] = keyValue.ToUpper();

      MessageLabel.Text = "";
    }
    else
    {
      MessageLabel.Text = "The key field must have four digits.";
      e.Cancel = true;
    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewInsertEventHandler 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]"
        insertcommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
        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(ByVal sender As Object, ByVal 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.AutoGenerateInsertButton = True
    customerDetailsView.AllowPaging = True
    
    Dim keyArray() As String = {"CustomerID"}
    customerDetailsView.DataKeyNames = keyArray
    
    ' Programmatically register the event-handling method
    ' for the ItemInserted event of a DetailsView control.
    AddHandler customerDetailsView.ItemInserting, AddressOf CustomerDetailsView_ItemInserting

    ' Add the DetailsView object to the Controls collection
    ' of the PlaceHolder control.
    DetailsViewPlaceHolder.Controls.Add(customerDetailsView)

  End Sub

  Sub CustomerDetailsView_ItemInserting(ByVal sender As Object, ByVal e As DetailsViewInsertEventArgs)
    
    ' Use the Values property to retrieve the key field value.
    Dim keyValue As String = e.Values("CustomerID").ToString()

    ' Insert the record only if the key field is four characters
    ' long; otherwise, cancel the insert operation.
    If keyValue.Length = 4 Then
    
      ' Change the key field value to upper case before inserting 
      ' the record in the data source.
      e.Values("CustomerID") = keyValue.ToUpper()
      
      MessageLabel.Text = ""
    
    Else
    
      MessageLabel.Text = "The key field must have four digits."
      e.Cancel = True
    
    End If

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewInsertEventHandler 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]"
        insertcommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
        connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
        runat="server"/>
            
    </form>
  </body>
</html>

В следующем примере кода показано, как декларативно добавить DetailsViewInsertEventHandler делегат в ItemInserting событие DetailsView элемента управления.


<%@ 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_ItemInserting(Object sender, 
    DetailsViewInsertEventArgs e)
  {
    // Use the Values property to retrieve the key field value.
    String keyValue = e.Values["CustomerID"].ToString();

    // Insert the record only if the key field is four characters
    // long; otherwise, cancel the insert operation.
    if (keyValue.Length == 4)
    {
      // Change the key field value to upper case before inserting 
      // the record in the data source.
      e.Values["CustomerID"] = keyValue.ToUpper();

      MessageLabel.Text = "";
    }
    else
    {
      MessageLabel.Text = "The key field must have four digits.";
      e.Cancel = true;
    }

  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewInsertEventHandler Example</h3>
                
        <asp:detailsview id="CustomerDetailsView"
          datasourceid="DetailsViewSource"
          datakeynames="CustomerID"
          autogenerateinsertbutton="true"  
          autogeneraterows="true"
          allowpaging="true"
          oniteminserting="CustomerDetailsView_ItemInserting" 
          runat="server">
               
          <fieldheaderstyle backcolor="Navy"
            forecolor="White"/>
                    
        </asp:detailsview>
        
        <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]"
          insertcommand="INSERT INTO [Customers]([CustomerID], 
            [CompanyName], [Address], [City], [PostalCode], 
            [Country]) VALUES (@CustomerID, @CompanyName, @Address, 
            @City, @PostalCode, @Country)"
          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_ItemInserting(ByVal sender As Object, _
    ByVal e As DetailsViewInsertEventArgs) _
    Handles CustomerDetailsView.ItemInserting
  
    ' Use the Values property to retrieve the key field value.
    Dim keyValue As String = e.Values("CustomerID").ToString()

    ' Insert the record only if the key field is four characters
    ' long; otherwise, cancel the insert operation.
    If keyValue.Length = 4 Then
    
      ' Change the key field value to upper case before inserting 
      ' the record in the data source.
      e.Values("CustomerID") = keyValue.ToUpper()
      
      MessageLabel.Text = ""
    
    Else
    
      MessageLabel.Text = "The key field must have four digits."
      e.Cancel = True
    
    End If

  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>DetailsViewInsertEventHandler Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>DetailsViewInsertEventHandler Example</h3>
                
        <asp:detailsview id="CustomerDetailsView"
          datasourceid="DetailsViewSource"
          datakeynames="CustomerID"
          autogenerateinsertbutton="true"  
          autogeneraterows="true"
          allowpaging="true"
          oniteminserting="CustomerDetailsView_ItemInserting" 
          runat="server">
               
          <fieldheaderstyle backcolor="Navy"
            forecolor="White"/>
                    
        </asp:detailsview>
        
        <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]"
          insertcommand="INSERT INTO [Customers]([CustomerID], 
            [CompanyName], [Address], [City], [PostalCode], 
            [Country]) VALUES (@CustomerID, @CompanyName, @Address, 
            @City, @PostalCode, @Country)"
          connectionstring=
          "<%$ ConnectionStrings:NorthWindConnectionString%>" 
          runat="server"/>
            
      </form>
  </body>
</html>

Элемент DetailsView управления вызывает ItemInserting событие при нажатии кнопки "Вставка" (кнопка со свойством CommandName "Вставка") в элементе управления, но перед DetailsView вставкой записи элементом управления. Это позволяет предоставить обработчик событий, выполняющий настраиваемую подпрограмму, например html-кодирование значений записи перед вставкой в источник данных, всякий раз при возникновении этого события.

При создании делегата DetailsViewInsertEventHandler вы определите метод, который будет обрабатывать событие. Чтобы связать событие с обработчиком событий, добавьте экземпляр делегата в событие. Обработчик событий вызывается всякий раз, когда происходит событие, если вы не удалите делегат. Дополнительные сведения о делегатах обработчика событий см. в разделе "Обработка и создание событий".

Методы расширения

Имя	Описание
GetMethodInfo(Delegate)	Возвращает объект, представляющий метод, представленный указанным делегатом.

Применяется к

См. также раздел

Обратная связь

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