HyperLinkField Costruttore

  • Riferimento

Definizione

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

Inizializza una nuova istanza della classe HyperLinkField.

public:
 HyperLinkField();
public HyperLinkField ();
Public Sub New ()

Esempio

Nell'esempio di codice seguente viene illustrato come usare il costruttore per aggiungere dinamicamente un oggetto a un HyperLinkFieldGridView controllo.


<%@ 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)
  {
  
    // Dynamically create field columns to display the desired
    // fields from the data source. This only needs to be done
    // the first time the page is loaded because the GridView
    // control persists its column fields. 
    if (!IsPostBack)
    {
      
      // Create a HyperLinkField object to display the company's 
      // name. Bind the CompanyName and HomePage fields from the
      // Northwind database to the caption and URL of the hyperlinks  
      // in the HyperLinkField field column. Note that the URLs
      // specified in the Northwind database might not be valid URLs.
      HyperLinkField companyNameBoundField = new HyperLinkField ();
      string[] dataNavigateUrlFields = { "HomePage" };

      companyNameBoundField.DataTextField = "CompanyName";
      companyNameBoundField.DataNavigateUrlFields = dataNavigateUrlFields;
      companyNameBoundField.HeaderText = "Company Name";
      companyNameBoundField.Target = "_blank";

      // Create a BoundField object to display the company's city.
      BoundField cityBoundField = new BoundField ();

      cityBoundField.DataField = "city";
      cityBoundField.HeaderText = "City";

      // Add the field columns to the Columns collection of the
      // GridView control.
      SuppliersGridView.Columns.Add (companyNameBoundField);
      SuppliersGridView.Columns.Add (cityBoundField);
      
    }
    
  }

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>HyperLinkField Constructor Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>HyperLinkField Constructor Example</h3>

      <asp:gridview id="SuppliersGridView" 
        datasourceid="SuppliersSqlDataSource" 
        autogeneratecolumns="False"
        runat="server">                
      </asp:gridview>
            
      <!-- This example uses Microsoft SQL Server and connects -->
      <!-- to the Northwind sample database.                   -->
      <asp:sqldatasource id="SuppliersSqlDataSource"  
        selectcommand="SELECT [SupplierID], [CompanyName], [City], [HomePage] FROM [Suppliers]"
        connectionstring="server=localhost;database=northwind;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)
  
    ' Dynamically create field columns to display the desired
    ' fields from the data source. This only needs to be done
    ' the first time the page is loaded because the GridView
    ' control persists its column fields. 
    If Not IsPostBack Then
      
      ' Create a HyperLinkField object to display the company's 
      ' name. Bind the CompanyName and HomePage fields from the
      ' Northwind database to the caption and URL of the hyperlinks  
      ' in the HyperLinkField field column. Note that the URLs
      ' specified in the Northwind database might not be valid URLs.
      Dim companyNameBoundField As New HyperLinkField
      Dim dataNavigateUrlFields() As String = {"HomePage"}

      companyNameBoundField.DataTextField = "CompanyName"
      companyNameBoundField.DataNavigateUrlFields = dataNavigateUrlFields
      companyNameBoundField.HeaderText = "Company Name"
      companyNameBoundField.Target = "_blank"

      ' Create a BoundField object to display the company's city.
      Dim cityBoundField As New BoundField

      cityBoundField.DataField = "city"
      cityBoundField.HeaderText = "City"

      ' Add the field columns to the Columns collection of the
      ' GridView control.
      SuppliersGridView.Columns.Add(companyNameBoundField)
      SuppliersGridView.Columns.Add(cityBoundField)
      
    End If
    
  End Sub

</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
  <head runat="server">
    <title>HyperLinkField Constructor Example</title>
</head>
<body>
    <form id="form1" runat="server">
        
      <h3>HyperLinkField Constructor Example</h3>

      <asp:gridview id="SuppliersGridView" 
        datasourceid="SuppliersSqlDataSource" 
        autogeneratecolumns="False"
        runat="server">                
      </asp:gridview>
            
      <!-- This example uses Microsoft SQL Server and connects -->
      <!-- to the Northwind sample database.                   -->
      <asp:sqldatasource id="SuppliersSqlDataSource"  
        selectcommand="SELECT [SupplierID], [CompanyName], [City], [HomePage] FROM [Suppliers]"
        connectionstring="server=localhost;database=northwind;integrated security=SSPI"
        runat="server">
      </asp:sqldatasource>
            
    </form>
  </body>
</html>

Commenti

Usare questo costruttore per inizializzare una nuova istanza della HyperLinkField classe. Questo costruttore viene comunemente usato quando si aggiungono campi a un controllo associato a dati creato dinamicamente.

Per aggiungere dinamicamente un oggetto a un HyperLinkField controllo associato a dati, creare un nuovo HyperLinkField oggetto, impostarne le proprietà e quindi aggiungerlo all'insieme di campi associato ai dati. Ad esempio, se si usa il controllo, aggiungere l'oggetto GridViewHyperLinkField all'insieme Columns .

Nota

Anche se è possibile aggiungere dinamicamente campi a un controllo associato a dati, è consigliabile dichiarare staticamente i campi e quindi visualizzati o nascosti, come appropriato. Dichiarando staticamente tutti i campi riduce le dimensioni dello stato di visualizzazione per il controllo associato ai dati padre.

Si applica a

Vedi anche