DataGridItemEventHandler Delegar

Definição

Espaço de Nomes:
System.Web.UI.WebControls
Assemblagem:
System.Web.dll

Representa o método que gere os ItemCreated eventos e ItemDataBound de um DataGrid controlo.

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

Parâmetros

sender
Object

A origem do evento.

e
DataGridItemEventArgs

A DataGridItemEventArgs que contém os dados do evento.

Exemplos

O exemplo de código seguinte demonstra como especificar e codificar um handler para o ItemCreated evento para mostrar a ordem em que os itens são criados no DataGrid controlo.

<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script language="C#" runat="server">
 
   DataTable Cart;
   DataView CartView;
 
   ICollection CreateDataSource() 
   {
      DataTable dt = new DataTable();
      DataRow dr;
 
      dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
      dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
      dt.Columns.Add(new DataColumn("CurrencyValue", typeof(double)));
 
      for (int i = 0; i < 10; i++) 
      {
         dr = dt.NewRow();
 
         dr[0] = i;
         dr[1] = "Item " + i.ToString();
         dr[2] = 1.23 * (i+1);
 
         dt.Rows.Add(dr);
      }
 
      DataView dv = new DataView(dt);
      return dv;
   }
 
   void Page_Load(Object sender, EventArgs e) 
   {
 
      if (!IsPostBack) 
      {
         // Need to load this data only once.
         ItemsGrid.DataSource = CreateDataSource();
         ItemsGrid.DataBind();
      }
 
   }
 
   void Item_Created(Object sender, DataGridItemEventArgs e) 
   {
 
      Label1.Text = Label1.Text + " " + e.Item.ItemIndex;
 
   }
 
</script>
 
<head runat="server">
    <title>DataGridItemEventArgs Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataGridItemEventArgs Example</h3>
 
      <asp:DataGrid id="ItemsGrid" runat="server"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="true"
           OnItemCreated="Item_Created"
           AutoGenerateColumns="true">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle>

         <FooterStyle BackColor="#00aaaa">
         </FooterStyle>
   
      </asp:DataGrid>
 
      <br />
 
      <asp:Label id="Label1" 
           Text="Order of items created: " 
           runat="server"/>

      <br />

      <asp:Label id="Label2" 
           Text="Note: The -1's refer to the header and footer." 
           runat="server"/>
 
   </form>
 
</body>
</html>

<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
<script language="VB" runat="server">
 
    Dim Cart As DataTable
    Dim CartView As DataView
 
    Function CreateDataSource() As ICollection
        Dim dt As New DataTable()
        Dim dr As DataRow
        
        dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
        dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
        dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
        
        Dim i As Integer
        For i = 0 To 9
            dr = dt.NewRow()
            
            dr(0) = i
            dr(1) = "Item " & i.ToString()
            dr(2) = 1.23 *(i + 1)
            
            dt.Rows.Add(dr)
        Next i
        
        Dim dv As New DataView(dt)
        Return dv
    End Function 'CreateDataSource


    Sub Page_Load(sender As Object, e As EventArgs)
        
        If Not IsPostBack Then
            ' Need to load this data only once.
            ItemsGrid.DataSource = CreateDataSource()
            ItemsGrid.DataBind()
        End If
    End Sub 'Page_Load
     

    Sub Item_Created(sender As Object, e As DataGridItemEventArgs)
        
        Label1.Text = Label1.Text & " " & e.Item.ItemIndex
    End Sub 'Item_Created 
 
</script>
 
<head runat="server">
    <title>DataGridItemEventArgs Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataGridItemEventArgs Example</h3>
 
      <asp:DataGrid id="ItemsGrid" runat="server"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="true"
           OnItemCreated="Item_Created"
           AutoGenerateColumns="true">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle>

         <FooterStyle BackColor="#00aaaa">
         </FooterStyle>
   
      </asp:DataGrid>
 
      <br />
 
      <asp:Label id="Label1" 
           Text="Order of items created: " 
           runat="server"/>

      <br />

      <asp:Label id="Label2" 
           Text="Note: The -1's refer to the header and footer." 
           runat="server"/>
 
   </form>
 
</body>
</html>


<%@ Page Language="C#" AutoEventWireup="True" Debug="true" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
   <script runat="server">
 
      ICollection CreateDataSource()
      {

         // Create sample data for the DataGrid control.
         DataTable dt = new DataTable();
         DataRow dr;
 
         // Define the columns of the table.
         dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(String)));
         dt.Columns.Add(new DataColumn("CurrencyValue", typeof(Double)));
 
         // Populate the table with sample values.
         for (int i=0; i<=10; i++) 
         {

            dr = dt.NewRow();
 
            dr[0] = i;
            dr[1] = "Item " + i.ToString();
            dr[2] = 1.23 * (i + 1);
 
            dt.Rows.Add(dr);
         
         }
 
         DataView dv = new DataView(dt);

         return dv;
      
      }
 
      void Page_Load(Object sender, EventArgs e)
      { 
 
         // Load sample data only once, when the page is first loaded.
         if (!IsPostBack)
         { 
         
            ItemsGrid.DataSource = CreateDataSource();
            ItemsGrid.DataBind();
         
         }

      }
 
      void Item_Bound(Object sender, DataGridItemEventArgs e) 
      {
 
         // Use the ItemDataBound event to customize the DataGrid control. 
         // The ItemDataBound event allows you to access the data before 
         // the item is displayed in the control. In this example, the 
         // ItemDataBound event is used to format the items in the 
         // CurrencyColumn in currency format.
         if((e.Item.ItemType == ListItemType.Item) || 
             (e.Item.ItemType == ListItemType.AlternatingItem))
         {
 
            // Retrieve the text of the CurrencyColumn from the DataGridItem
            // and convert the value to a Double.
            Double Price = Convert.ToDouble(e.Item.Cells[2].Text);

            // Format the value as currency and redisplay it in the DataGrid.
            e.Item.Cells[2].Text = Price.ToString("c");
        
         }         
 
      }
 
</script>
 
<head runat="server">
    <title>DataGrid ItemDataBound Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataGrid ItemDataBound Example</h3>
 
      <asp:DataGrid id="ItemsGrid" runat="server"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="true"
           OnItemDataBound="Item_Bound">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle>

         <FooterStyle BackColor="#00aaaa">
         </FooterStyle>
   
      </asp:DataGrid>

   </form>
 
</body>
</html>


<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
   <script runat="server">
 
      Function CreateDataSource() As ICollection

         ' Create sample data for the DataGrid control.
         Dim dt As DataTable = New DataTable()
         Dim dr As DataRow 
 
         ' Define the columns of the table.
         dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
         dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
         dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
 
         ' Populate the table with sample values.
         Dim i As Integer         

         For i=0 To 10 

            dr = dt.NewRow()
 
            dr(0) = i
            dr(1) = "Item " & i.ToString()
            dr(2) = 1.23 * (i + 1)
 
            dt.Rows.Add(dr)
         
         Next i
 
         Dim dv As DataView = New DataView(dt)

         return dv
      
      End Function
 
      Sub Page_Load(sender As Object, e As EventArgs)
 
         ' Load sample data only once, when the page is first loaded.
         If Not IsPostBack Then
         
            ItemsGrid.DataSource = CreateDataSource()
            ItemsGrid.DataBind()
         
         End If

      End Sub
 
      Sub Item_Bound(sender As Object, e As DataGridItemEventArgs) 
 
         ' Use the ItemDataBound event to customize the DataGrid control. 
         ' The ItemDataBound event allows you to access the data before 
         ' the item is displayed in the control. In this example, the 
         ' ItemDataBound event is used to format the items in the 
         ' CurrencyColumn in currency format.
         If e.Item.ItemType = ListItemType.Item Or _
             e.Item.ItemType = ListItemType.AlternatingItem Then
 
            ' Retrieve the text of the CurrencyColumn from the DataGridItem
            ' and convert the value to a Double.
            Dim Price As Double = Convert.ToDouble(e.Item.Cells(2).Text)

            ' Format the value as currency and redisplay it in the DataGrid.
            e.Item.Cells(2).Text = Price.ToString("c")
        
         End If         
 
      End Sub
 
</script>
 
<head runat="server">
    <title>DataGrid ItemDataBound Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataGrid ItemDataBound Example</h3>
 
      <asp:DataGrid id="ItemsGrid" runat="server"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="true"
           OnItemDataBound="Item_Bound">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle>

         <FooterStyle BackColor="#00aaaa">
         </FooterStyle>
   
      </asp:DataGrid>

   </form>
 
</body>
</html>


<%@ Page Language="C#" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
   <script runat="server">
 
      ICollection CreateDataSource()
      {

         // Create sample data for the DataGrid control.
         DataTable dt = new DataTable();
         DataRow dr;
 
         // Define the columns of the table.
         dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(String)));
         dt.Columns.Add(new DataColumn("CurrencyValue", typeof(Double)));
 
         // Populate the table with sample values.
         for (int i=0; i<=10; i++) 
         {

            dr = dt.NewRow();
 
            dr[0] = i;
            dr[1] = "Item " + i.ToString();
            dr[2] = 1.23 * (i + 1);
 
            dt.Rows.Add(dr);
         
         }
 
         DataView dv = new DataView(dt);

         return dv;
      
      }
 
      void Page_Load(Object sender, EventArgs e)
      { 
 
         // Manually register the event-handling method for the  
         // ItemDataBound event of the DataGrid control.
         ItemsGrid.ItemDataBound += 
             new DataGridItemEventHandler(this.Item_Bound);

         // Load sample data only once, when the page is first loaded.
         if (!IsPostBack)
         { 
         
            ItemsGrid.DataSource = CreateDataSource();
            ItemsGrid.DataBind();
         
         }

      }
 
      void Item_Bound(Object sender, DataGridItemEventArgs e) 
      {
 
         // Use the ItemDataBound event to customize the DataGrid control. 
         // The ItemDataBound event allows you to access the data before 
         // the item is displayed in the control. In this example, the 
         // ItemDataBound event is used to format the items in the 
         // CurrencyColumn in currency format.
         if((e.Item.ItemType == ListItemType.Item) ||
             (e.Item.ItemType == ListItemType.AlternatingItem))
         {
 
            // Retrieve the text of the CurrencyColumn from the DataGridItem
            // and convert the value to a Double.
            Double Price = Convert.ToDouble(e.Item.Cells[2].Text);

            // Format the value as currency and redisplay it in the DataGrid.
            e.Item.Cells[2].Text = Price.ToString("c");
        
         }         
 
      }
 
</script>
 
<head runat="server">
    <title>DataGrid ItemDataBound Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataGrid ItemDataBound Example</h3>
 
      <asp:DataGrid id="ItemsGrid" runat="server"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="true">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle>

         <FooterStyle BackColor="#00aaaa">
         </FooterStyle>
   
      </asp:DataGrid>

   </form>
 
</body>
</html>


<%@ Page Language="VB" AutoEventWireup="True" %>
<%@ Import Namespace="System.Data" %>
 
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN"
    "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml" >
   <script runat="server">
 
      Function CreateDataSource() As ICollection

         ' Create sample data for the DataGrid control.
         Dim dt As DataTable = New DataTable()
         Dim dr As DataRow 
 
         ' Define the columns of the table.
         dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
         dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
         dt.Columns.Add(New DataColumn("CurrencyValue", GetType(Double)))
 
         ' Populate the table with sample values.
         Dim i As Integer         

         For i=0 To 10 

            dr = dt.NewRow()
 
            dr(0) = i
            dr(1) = "Item " & i.ToString()
            dr(2) = 1.23 * (i + 1)
 
            dt.Rows.Add(dr)
         
         Next i
 
         Dim dv As DataView = New DataView(dt)

         return dv
      
      End Function
 
      Sub Page_Load(sender As Object, e As EventArgs)

         ' Manually register the event-handling method for the  
         ' ItemDataBound event of the DataGrid control.
         AddHandler ItemsGrid.ItemDataBound, AddressOf Item_Bound
 
         ' Load sample data only once, when the page is first loaded.
         If Not IsPostBack Then
         
            ItemsGrid.DataSource = CreateDataSource()
            ItemsGrid.DataBind()
         
         End If

      End Sub
 
      Sub Item_Bound(sender As Object, e As DataGridItemEventArgs) 
 
         ' Use the ItemDataBound event to customize the DataGrid control. 
         ' The ItemDataBound event allows you to access the data before 
         ' the item is displayed in the control. In this example, the 
         ' ItemDataBound event is used to format the items in the 
         ' CurrencyColumn in currency format.
         If e.Item.ItemType = ListItemType.Item Or _
             e.Item.ItemType = ListItemType.AlternatingItem Then
 
            ' Retrieve the text of the CurrencyColumn from the DataGridItem
            ' and convert the value to a Double.
            Dim Price As Double = Convert.ToDouble(e.Item.Cells(2).Text)

            ' Format the value as currency and redisplay it in the DataGrid.
            e.Item.Cells(2).Text = Price.ToString("c")
        
         End If         
 
      End Sub
 
</script>
 
<head runat="server">
    <title>DataGrid ItemDataBound Example</title>
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataGrid ItemDataBound Example</h3>
 
      <asp:DataGrid id="ItemsGrid" runat="server"
           BorderColor="black"
           BorderWidth="1"
           CellPadding="3"
           ShowFooter="true">

         <HeaderStyle BackColor="#00aaaa">
         </HeaderStyle>

         <FooterStyle BackColor="#00aaaa">
         </FooterStyle>
   
      </asp:DataGrid>

   </form>
 
</body>
</html>

Observações

O ItemCreated evento é ativado quando um item no DataGrid controlo é criado.

O ItemDataBound evento é ativado quando um item no DataGrid controlo está ligado a uma fonte de dados.

Quando cria um DataGridItemEventHandler delegado, identifica o método que irá gerir o evento. Para associar o evento ao seu gestor de eventos, adicione uma instância do delegado ao evento. O gestor de eventos é chamado sempre que o evento ocorre, a menos que remova o delegado. Para mais informações sobre os delegados gestores de eventos, consulte Gestão e Levantamento de Eventos.

Métodos da Extensão

Name Description
GetMethodInfo(Delegate)

Obtém um objeto que representa o método representado pelo delegado especificado.

Aplica-se a

Ver também