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LinkButton.OnPreRender(EventArgs) Método

Definição

Aciona o evento PreRender.

protected:
 override void OnPreRender(EventArgs ^ e);
protected public:
 override void OnPreRender(EventArgs ^ e);
protected override void OnPreRender (EventArgs e);
protected internal override void OnPreRender (EventArgs e);
override this.OnPreRender : EventArgs -> unit
Protected Overrides Sub OnPreRender (e As EventArgs)
Protected Friend Overrides Sub OnPreRender (e As EventArgs)

Parâmetros

e
EventArgs

Um objeto EventArgs que contém os dados do evento.

Exemplos

O exemplo de código a seguir demonstra como substituir o OnPreRender método para que uma borda nunca seja exibida em um controle personalizado LinkButton .

<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.CS.Controls" Assembly="Samples.AspNet.CS" %>
<%@ Page Language="C#" AutoEventWireup="True" %>
<!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>Custom LinkButton - OnPreRender - C# Example</title>
    <script runat="server">
      void LinkButton1_Command(Object sender, CommandEventArgs e) 
      {
        // Redirect to the Microsoft home page.
        Response.Redirect("http://www.microsoft.com/");
      }
    </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom LinkButton - OnPreRender - C# Example</h3>
            
            <aspSample:CustomLinkButtonOnPreRender 
              id="LinkButton1" 
              runat="server" 
              OnCommand="LinkButton1_Command" 
              ToolTip="Microsoft Home">Microsoft Corp.
            </aspSample:CustomLinkButtonOnPreRender>
            
        </form>
    </body>
</html>
<%@ Register TagPrefix="aspSample" Namespace="Samples.AspNet.VB.Controls" Assembly="Samples.AspNet.VB" %>
<%@ Page Language="VB" AutoEventWireup="True" %>
<!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>Custom LinkButton - OnPreRender - VB.NET Example</title>
        <script runat="server">
            Sub LinkButton1_Command(sender As Object, e As CommandEventArgs)
                ' Redirect to the Microsoft home page.
                Response.Redirect("http://www.microsoft.com/")
            End Sub
        </script>
    </head>
    <body>
        <form id="Form1" method="post" runat="server">
            <h3>Custom LinkButton - OnPreRender - VB.NET Example</h3>
            
            <aspSample:CustomLinkButtonOnPreRender id="LinkButton1" 
             runat="server" OnCommand="LinkButton1_Command" 
             ToolTip="Microsoft Home">Microsoft Corp.</aspSample:CustomLinkButtonOnPreRender>

        </form>
    </body>
</html>
using System.Web;
using System.Security.Permissions;

namespace Samples.AspNet.CS.Controls
{
  [AspNetHostingPermission(SecurityAction.Demand, Level=AspNetHostingPermissionLevel.Minimal)]
  public sealed class CustomLinkButtonOnPreRender : System.Web.UI.WebControls.LinkButton
  {
    protected override void OnPreRender(System.EventArgs e)
    {
      // Run the OnPreRender method on the base class.
      base.OnPreRender(e);

      // Always display the LinkButton without a border.
      this.BorderWidth =  System.Web.UI.WebControls.Unit.Point(0);
    }
  }
}
<AspNetHostingPermission(SecurityAction.Demand, Level:=AspNetHostingPermissionLevel.Minimal)> _
Public NotInheritable Class CustomLinkButtonOnPreRender
    Inherits System.Web.UI.WebControls.LinkButton

    Protected Overrides Sub OnPreRender(ByVal e As System.EventArgs)

        ' Run the OnPreRender method on the base class.
        MyBase.OnPreRender(e)

        ' Always display the LinkButton without a border.
        Me.BorderWidth = System.Web.UI.WebControls.Unit.Point(0)
    End Sub
End Class

Comentários

O OnPreRender método notifica o LinkButton controle para executar as etapas de pré-geração necessárias antes de salvar o estado do modo de exibição e renderizar o conteúdo para o cliente.

Aplica-se a

Confira também