GridViewUpdateEventHandler Delegasikan

Referensi

Definisi

Ruang nama:: System.Web.UI.WebControls

Rakitan:: System.Web.dll

Penting

Beberapa informasi terkait produk prarilis yang dapat diubah secara signifikan sebelum dirilis. Microsoft tidak memberikan jaminan, tersirat maupun tersurat, sehubungan dengan informasi yang diberikan di sini.

Mewakili metode yang menangani RowUpdating peristiwa GridView kontrol.

public delegate void GridViewUpdateEventHandler(System::Object ^ sender, GridViewUpdateEventArgs ^ e);

public delegate void GridViewUpdateEventHandler(object sender, GridViewUpdateEventArgs e);

type GridViewUpdateEventHandler = delegate of obj * GridViewUpdateEventArgs -> unit

Public Delegate Sub GridViewUpdateEventHandler(sender As Object, e As GridViewUpdateEventArgs)

Parameter

sender: Object

Sumber dari peristiwa tersebut.

e: GridViewUpdateEventArgs

Objek GridViewUpdateEventArgs yang berisi data peristiwa.

Contoh

Contoh berikut menunjukkan cara menambahkan GridViewUpdateEventHandler delegasi secara terprogram ke RowUpdating peristiwa GridView kontrol.


<%@ 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 GridView object.
        GridView authorGridView = new GridView();
         
        // Set the GridView object's properties.
        authorGridView.ID = "AuthorGridView";
        authorGridView.DataSourceID = "AuthorsSqlDataSource"; 
        authorGridView.AutoGenerateColumns = true;
        authorGridView.AutoGenerateEditButton = true;
        authorGridView.DataKeyNames = new String[] {"au_id"};
        
        // Programmatically register the event-handling method.
        authorGridView.RowUpdating += new GridViewUpdateEventHandler(this.AuthorsGridView_RowUpdating);
        
        // Add the GridView object to the Controls collection
        // of the PlaceHolder control.
        GridViewPlaceHolder.Controls.Add(authorGridView);
        
    }
    
    void AuthorsGridView_RowUpdating(Object sender, GridViewUpdateEventArgs e)
    {
     
        // HTML-encode all user-provided values before updating
        // the data source.
        foreach (DictionaryEntry entry in e.NewValues)
        {
    
            e.NewValues[entry.Key] = Server.HtmlEncode(entry.Value.ToString());
    
        }
        
    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
    <head runat="server">
    <title>GridViewUpdateEventHandler Example</title>
</head>
<body>
        <form id="form1" runat="server">
        
            <h3>GridViewUpdateEventHandler Example</h3>
            
            <asp:label id="Message"
                forecolor="Red"
                runat="server"/>
                
            <br/>
            
            <asp:placeholder id="GridViewPlaceHolder"
                runat="Server"/>
            
            <!-- This example uses Microsoft SQL Server and connects -->
            <!-- to the Pubs sample database.                        -->
            <asp:sqldatasource id="AuthorsSqlDataSource"  
                selectcommand="SELECT [au_id], [au_lname], [au_fname], [address], [city], [state], [zip] FROM [authors]"
                updatecommand="UPDATE authors SET au_lname=@au_lname, au_fname=@au_fname, address=@address, city=@city, state=@state, zip=@zip WHERE (authors.au_id = @au_id)"
                connectionstring="server=localhost;database=pubs;integrated security=SSPI"
                runat="server">
            </asp:sqldatasource>
            
        </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 GridView object.
        Dim authorGridView As GridView = New GridView
         
        ' Set the GridView object's properties.
        authorGridView.ID = "AuthorGridView"
        authorGridView.DataSourceID = "AuthorsSqlDataSource"
        authorGridView.AutoGenerateColumns = True
        authorGridView.AutoGenerateEditButton = True
        authorGridView.DataKeyNames = New [String]() {"au_id"}
        
        ' Programmatically register the event-handling method.
        AddHandler authorGridView.RowUpdating, AddressOf AuthorsGridView_RowUpdating
        
        ' Add the GridView object to the Controls collection
        ' of the PlaceHolder control.
        GridViewPlaceHolder.Controls.Add(authorGridView)
        
    End Sub
    
    Sub AuthorsGridView_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
     
        ' HTML-encode all user-provided values before updating
        ' the data source.
        Dim i As Integer
        
        For i = 0 To e.NewValues.Count - 1
            
            Dim entry As DictionaryEntry = e.NewValues(i)
            e.NewValues(entry.Key) = Server.HtmlEncode(entry.Value.ToString())
    
        Next i
        
    End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
    <head runat="server">
    <title>GridViewUpdateEventHandler Example</title>
</head>
<body>
        <form id="form1" runat="server">
        
            <h3>GridViewUpdateEventHandler Example</h3>
            
            <asp:label id="Message"
                forecolor="Red"
                runat="server"/>
                
            <br/>
            
            <asp:placeholder id="GridViewPlaceHolder"
                runat="Server"/>
            
            <!-- This example uses Microsoft SQL Server and connects -->
            <!-- to the Pubs sample database.                        -->
            <asp:sqldatasource id="AuthorsSqlDataSource"  
                selectcommand="SELECT [au_id], [au_lname], [au_fname], [address], [city], [state], [zip] FROM [authors]"
                updatecommand="UPDATE authors SET au_lname=@au_lname, au_fname=@au_fname, address=@address, city=@city, state=@state, zip=@zip WHERE (authors.au_id = @au_id)"
                connectionstring="server=localhost;database=pubs;integrated security=SSPI"
                runat="server">
            </asp:sqldatasource>
            
        </form>
    </body>
</html>

Contoh berikut menunjukkan cara menambahkan GridViewUpdateEventHandler delegasi secara deklaratif ke RowUpdating peristiwa GridView kontrol.


<%@ 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 CustomersGridView_RowUpdating(Object sender, GridViewUpdateEventArgs e)
  {
     
    // Iterate through the NewValues collection and HTML encode all 
    // user-provided values before updating the data source.
    foreach (DictionaryEntry entry in e.NewValues)
    {
    
      e.NewValues[entry.Key] = Server.HtmlEncode(entry.Value.ToString());
    
    }
        
  }
       
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowUpdating Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowUpdating Example</h3>
            
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames property as read-only.    -->
      <!-- No input controls are rendered for these columns in     -->
      <!-- edit mode.                                              -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogenerateeditbutton="true"
        allowpaging="true" 
        datakeynames="CustomerID"
        onrowupdating="CustomersGridView_RowUpdating"  
        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]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </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 CustomersGridView_RowUpdating(ByVal sender As Object, ByVal e As GridViewUpdateEventArgs)
    
    ' Use the CopyTo method to copy the DictionaryEntry objects in the 
    ' NewValues collection to an array.
    Dim records(e.NewValues.Count - 1) As DictionaryEntry
    e.NewValues.CopyTo(records, 0)
    
    ' Iterate through the array and HTML encode all user-provided values 
    ' before updating the data source.
    Dim entry As DictionaryEntry
    For Each entry In records
            
      e.NewValues(entry.Key) = Server.HtmlEncode(entry.Value.ToString())
      
    Next
        
  End Sub
       
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>GridView RowUpdating Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>GridView RowUpdating Example</h3>
            
      <!-- The GridView control automatically sets the columns     -->
      <!-- specified in the datakeynames property as read-only.    -->
      <!-- No input controls are rendered for these columns in     -->
      <!-- edit mode.                                              -->
      <asp:gridview id="CustomersGridView" 
        datasourceid="CustomersSqlDataSource" 
        autogeneratecolumns="true"
        autogenerateeditbutton="true"
        allowpaging="true" 
        datakeynames="CustomerID"
        onrowupdating="CustomersGridView_RowUpdating"  
        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]"
        updatecommand="Update Customers SET CompanyName=@CompanyName, Address=@Address, City=@City, PostalCode=@PostalCode, Country=@Country WHERE (CustomerID = @CustomerID)"
        connectionstring="<%$ ConnectionStrings:NorthWindConnectionString%>"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

Keterangan

Peristiwa RowUpdating dimunculkan saat tombol Perbarui baris diklik, tetapi sebelum GridView kontrol memperbarui baris. Ini memungkinkan Anda untuk menyediakan metode penanganan peristiwa yang melakukan rutinitas kustom, seperti membatalkan operasi pembaruan, setiap kali peristiwa ini terjadi.

Saat membuat GridViewUpdateEventHandler delegasi, Anda mengidentifikasi metode yang akan menangani peristiwa. Untuk mengaitkan peristiwa dengan penanganan aktivitas Anda, tambahkan instans delegasi ke peristiwa. Penanganan aktivitas dipanggil setiap kali peristiwa terjadi, kecuali Anda menghapus delegasi. Untuk informasi selengkapnya tentang delegasi penanganan aktivitas, lihat Menangani dan Menaikkan Peristiwa.

Metode Ekstensi

GetMethodInfo(Delegate)

Mendapatkan objek yang mewakili metode yang diwakili oleh delegasi yang ditentukan.

Berlaku untuk