DataListCommandEventArgs.CommandSource Proprietà

  • Riferimento

Definizione

Spazio dei nomi:
System.Web.UI.WebControls
Assembly:
System.Web.dll

Ottiene l'origine del comando.

public:
 property System::Object ^ CommandSource { System::Object ^ get(); };
public object CommandSource { get; }
member this.CommandSource : obj
Public ReadOnly Property CommandSource As Object

Valore della proprietà

Object

Origine del comando.

Esempio

Nell'esempio seguente viene illustrato come utilizzare la CommandSource proprietà per determinare il comando selezionato dall'utente. Esegue quindi l'azione appropriata in base al comando .

<%@ 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" >
<head>
    <title>DataListCommandEventArgs Example</title>
<script language="c#" runat="server">
 
      ICollection CreateDataSource() 
      {
         
         DataTable dt = new DataTable();
         DataRow dr;
 
         // Create a DataTable.
         dt.Columns.Add(new DataColumn("IntegerValue", typeof(Int32)));
         dt.Columns.Add(new DataColumn("StringValue", typeof(string)));
         dt.Columns.Add(new DataColumn("DateTimeValue", typeof(DateTime)));
 
         // Create sample data.
         for (int i = 1; i <= 9; i++) 
         {
            dr = dt.NewRow();
            dr[0] = i;
            dr[1] = "Item " + i.ToString();
            dr[2] = DateTime.Now.ToShortTimeString();
            dt.Rows.Add(dr);
         }
          
 
         // Return a DataView to the DataTable.
         DataView dv = new DataView(dt);
         return dv;
         
      }
 
      void Page_Load(Object sender, EventArgs e) 
      {
         
         if (!IsPostBack)
            BindList();
 
      }
 
      void BindList() 
      {

         DataList1.DataSource = CreateDataSource();
         DataList1.DataBind();

      }
     
      void DataList_ItemCommand(object sender, DataListCommandEventArgs e) 
      {          
         if (((LinkButton)e.CommandSource).CommandName == "select")
            DataList1.SelectedIndex = e.Item.ItemIndex;
         
         BindList();
      }
 
   </script>
 
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataListCommandEventArgs Example</h3>
 
      <asp:DataList id="DataList1"                                                
                    GridLines="Both"                                                       
                    OnItemCommand="DataList_ItemCommand"
                    runat="server">

         <HeaderTemplate>
            Items
         </HeaderTemplate>

         <ItemTemplate>
            <asp:LinkButton id="button1"
                            Text="Show details" 
                            CommandName="select" 
                            runat="server"/>
            <%# DataBinder.Eval(Container.DataItem, "StringValue") %>
         </ItemTemplate>

         <SelectedItemTemplate>
            Item:
            <%# DataBinder.Eval(Container.DataItem, "StringValue") %>
            <br />
            Order Date:
            <%# DataBinder.Eval(Container.DataItem, "DateTimeValue", "{0:d}") %>
            <br />
            Quantity:
            <%# DataBinder.Eval(Container.DataItem, "IntegerValue", "{0:N1}") %>
            <br />
         </SelectedItemTemplate>
 
      </asp:DataList>

   </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" >
<head>
    <title>DataListCommandEventArgs Example</title>
<script language="VB" runat="server">
 
    Function CreateDataSource() As ICollection
        
        Dim dt As New DataTable()
        Dim dr As DataRow
        
        ' Create a DataTable.
        dt.Columns.Add(New DataColumn("IntegerValue", GetType(Int32)))
        dt.Columns.Add(New DataColumn("StringValue", GetType(String)))
        dt.Columns.Add(New DataColumn("DateTimeValue", GetType(DateTime)))
        
        ' Create sample data.
        Dim i As Integer
        For i = 1 To 9
            dr = dt.NewRow()
            dr(0) = i
            dr(1) = "Item " & i.ToString()
            dr(2) = DateTime.Now.ToShortTimeString()
            dt.Rows.Add(dr)
        Next i
        
        
        ' Return a DataView to the DataTable.
        Dim dv As New DataView(dt)
        Return dv
    End Function 'CreateDataSource
     

    Sub Page_Load(sender As Object, e As EventArgs)
        
        If Not IsPostBack Then
            BindList()
        End If 
    End Sub 'Page_Load


    Sub BindList()
        
        DataList1.DataSource = CreateDataSource()
        DataList1.DataBind()
    End Sub 'BindList
     

    Sub DataList_ItemCommand(sender As Object, e As DataListCommandEventArgs)
        If CType(e.CommandSource, LinkButton).CommandName = "select" Then
            DataList1.SelectedIndex = e.Item.ItemIndex
        End If 
        BindList()
    End Sub 'DataList_ItemCommand
     
   </script>
 
</head>
<body>
 
   <form id="form1" runat="server">

      <h3>DataListCommandEventArgs Example</h3>
 
      <asp:DataList id="DataList1"                                                
                    GridLines="Both"                                                       
                    OnItemCommand="DataList_ItemCommand"
                    runat="server">

         <HeaderTemplate>
            Items
         </HeaderTemplate>

         <ItemTemplate>
            <asp:LinkButton id="button1"
                            Text="Show details" 
                            CommandName="select" 
                            runat="server"/>
            <%# DataBinder.Eval(Container.DataItem, "StringValue") %>
         </ItemTemplate>

         <SelectedItemTemplate>
            Item:
            <%# DataBinder.Eval(Container.DataItem, "StringValue") %>
            <br />
            Order Date:
            <%# DataBinder.Eval(Container.DataItem, "DateTimeValue", "{0:d}") %>
            <br />
            Quantity:
            <%# DataBinder.Eval(Container.DataItem, "IntegerValue", "{0:N1}") %>
            <br />
         </SelectedItemTemplate>
 
      </asp:DataList>

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

Commenti

Utilizzare la CommandSource proprietà per determinare l'origine del comando che ha generato l'evento. Questa proprietà viene comunemente usata per determinare quale comando genera l'evento. È quindi possibile eseguire un'azione appropriata, in base al comando .

Si applica a

Vedi anche