DetailsView.DataItemCount Proprietà

  • Riferimento

Definizione

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

Ottiene il numero di elementi presenti nell'origine dati sottostante.

public:
 property int DataItemCount { int get(); };
[System.ComponentModel.Browsable(false)]
public int DataItemCount { get; }
[<System.ComponentModel.Browsable(false)>]
member this.DataItemCount : int
Public ReadOnly Property DataItemCount As Integer

Valore della proprietà

Int32

Numero di elementi presenti nell'origine dati sottostante.

Attributi
BrowsableAttribute

Esempio

Nell'esempio di codice seguente viene illustrato come usare la DataItemCount proprietà per determinare il numero di elementi nell'origine dati. Questo valore viene usato per visualizzare il conteggio delle pagine in un controllo contenuto in una Label riga del pager personalizzata.

<%@ 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">

    protected void CustomerDetailView_DataBound(object sender, EventArgs e)
    {

      // Get the pager row.
      DetailsViewRow pagerRow = CustomerDetailView.BottomPagerRow;

      // Get the Label controls that display the current page information 
      // from the pager row.
      Label pageNum = (Label)pagerRow.Cells[0].FindControl("PageNumberLabel");
      Label totalNum = (Label)pagerRow.Cells[0].FindControl("TotalPagesLabel");

      if ((pageNum != null) && (totalNum != null))
      {
          // Update the Label controls with the current page values.
          int page = CustomerDetailView.DataItemIndex + 1;
          int count = CustomerDetailView.DataItemCount;

          pageNum.Text = page.ToString();
          totalNum.Text = count.ToString();
      }
    }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >

  <head runat="server">
    <title>DetailsView PagerTemplate Example</title>
</head>
<body>
    <form id="Form1" runat="server">
        
      <h3>DetailsView PagerTemplate Example</h3>
                
        <!-- Notice that the LinkButton controls in the pager   -->
        <!-- template have their CommandName properties set.    -->
        <!-- The DetailsView control automatically recognizes   -->
        <!-- certain command names and performs the appropriate -->
        <!-- operation. In this example, the CommandName        -->
        <!-- properties are set "Page" and the CommandArgument  -->
        <!-- properties are set to "Next" and "Prev", which     -->
        <!-- causes the DetailsView control to navigate to the  -->
        <!-- next and previous record, respectively.            -->        
        <asp:detailsview id="CustomerDetailView"
          datasourceid="DetailsViewSource"
          autogeneraterows="true" 
          allowpaging="true"
        
          runat="server" OnDataBound="CustomerDetailView_DataBound">
               
          <headerstyle backcolor="Navy"
            forecolor="White"/>
            
          <pagerstyle VerticalAlign="Bottom" />
            
          <pagertemplate>
          
            <table width="100%">
              <tr>
                <td>
                  <asp:LinkButton id="PreviousButton"
                    text="<"
                    CommandName="Page"
                    CommandArgument="Prev"
                    runat="Server"/>
                  <asp:LinkButton id="NextButton"
                    text=">"
                    CommandName="Page"
                    CommandArgument="Next"
                    runat="Server"/> 
                </td>
                <td align="right">                
                  Page <asp:Label id="PageNumberLabel" runat="server" /> 
                  of <asp:Label id="TotalPagesLabel" runat="server" />                
                </td>
              </tr>
            </table>          
          </pagertemplate>   
                    
        </asp:detailsview>
        
        <!-- 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" runat="server" 
          ConnectionString=
            "<%$ ConnectionStrings:NorthWindConnectionString%>"
            InsertCommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
          SelectCommand="Select [CustomerID], [CompanyName], 
            [Address], [City], [PostalCode], [Country] From 
            [Customers]">
        </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">

    Protected Sub CustomerDetailView_DataBound(ByVal sender As Object, ByVal e As EventArgs)
        ' Get the pager row.
        Dim pagerRow As DetailsViewRow = CustomerDetailView.BottomPagerRow

        ' Get the Label controls that display the current page information 
        ' from the pager row.
        Dim pageNum As Label = CType(pagerRow.Cells(0).FindControl("PageNumberLabel"), Label)
        Dim totalNum As Label = CType(pagerRow.Cells(0).FindControl("TotalPagesLabel"), Label)
        
        If (pageNum IsNot Nothing) And (totalNum IsNot Nothing) Then
            ' Update the Label controls with the current page values.
            Dim page As Integer = CustomerDetailView.DataItemIndex + 1
            Dim count As Integer = CustomerDetailView.DataItemCount

            pageNum.Text = page.ToString()
            totalNum.Text = count.ToString()
        End If
    End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >

  <head runat="server">
    <title>DetailsView PagerTemplate Example</title>
</head>
<body>
    <form id="Form1" runat="server">
        
      <h3>DetailsView PagerTemplate Example</h3>
                
        <!-- Notice that the LinkButton controls in the pager   -->
        <!-- template have their CommandName properties set.    -->
        <!-- The DetailsView control automatically recognizes   -->
        <!-- certain command names and performs the appropriate -->
        <!-- operation. In this example, the CommandName        -->
        <!-- properties are set "Page" and the CommandArgument  -->
        <!-- properties are set to "Next" and "Prev", which     -->
        <!-- causes the DetailsView control to navigate to the  -->
        <!-- next and previous record, respectively.            -->        
        <asp:detailsview id="CustomerDetailView"
          datasourceid="DetailsViewSource"
          autogeneraterows="true" 
          allowpaging="true"
        
          runat="server" OnDataBound="CustomerDetailView_DataBound">
               
          <headerstyle backcolor="Navy"
            forecolor="White"/>
            
          <pagerstyle VerticalAlign="Bottom" />
            
          <pagertemplate>
          
            <table width="100%">
              <tr>
                <td>
                  <asp:LinkButton id="PreviousButton"
                    text="<"
                    CommandName="Page"
                    CommandArgument="Prev"
                    runat="Server"/>
                  <asp:LinkButton id="NextButton"
                    text=">"
                    CommandName="Page"
                    CommandArgument="Next"
                    runat="Server"/> 
                </td>
                <td align="right">                
                  Page <asp:Label id="PageNumberLabel" runat="server" /> 
                  of <asp:Label id="TotalPagesLabel" runat="server" />                
                </td>
              </tr>
            </table>          
          </pagertemplate>   
                    
        </asp:detailsview>
        
        <!-- 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" runat="server" 
          ConnectionString=
            "<%$ ConnectionStrings:NorthWindConnectionString%>"
            InsertCommand="INSERT INTO [Customers]([CustomerID], [CompanyName], [Address], [City], [PostalCode], [Country]) VALUES (@CustomerID, @CompanyName, @Address, @City, @PostalCode, @Country)"
          SelectCommand="Select [CustomerID], [CompanyName], 
            [Address], [City], [PostalCode], [Country] From 
            [Customers]">
        </asp:SqlDataSource>
    </form>
  </body>
</html>

Commenti

Quando la funzionalità di paging è abilitata (impostando la proprietà su true), utilizzare DataItemCount la proprietà per determinare il AllowPaging numero totale di record nell'origine dati sottostante.

Nota

Poiché il DetailsView controllo visualizza un solo record alla volta, questo valore corrisponde anche al numero totale di pagine necessarie per visualizzare ogni record nell'origine dati.

Per determinare l'indice del record corrente dall'origine dati sottostante, usare la DataItemIndex proprietà .

Si applica a

Vedi anche