Login.OnLoggingIn(LoginCancelEventArgs) Metode

Referensi

Definisi

Ruang nama:: System.Web.UI.WebControls

Rakitan:: System.Web.dll

Penting

Beberapa informasi terkait produk prarilis yang dapat diubah secara signifikan sebelum dirilis. Microsoft tidak memberikan jaminan, tersirat maupun tersurat, sehubungan dengan informasi yang diberikan di sini.

Menaikkan LoggingIn peristiwa saat pengguna mengirimkan informasi masuk tetapi sebelum autentikasi berlangsung.

protected:
 virtual void OnLoggingIn(System::Web::UI::WebControls::LoginCancelEventArgs ^ e);

protected virtual void OnLoggingIn (System.Web.UI.WebControls.LoginCancelEventArgs e);

abstract member OnLoggingIn : System.Web.UI.WebControls.LoginCancelEventArgs -> unit
override this.OnLoggingIn : System.Web.UI.WebControls.LoginCancelEventArgs -> unit

Protected Overridable Sub OnLoggingIn (e As LoginCancelEventArgs)

Parameter

e: LoginCancelEventArgs

yang LoginCancelEventArgs berisi data peristiwa.

Contoh

Contoh kode berikut menggunakan LoggingIn peristiwa untuk memastikan bahwa pengguna telah memasukkan alamat email yang terbentuk dengan baik di UserName properti . Jika tidak, penanganan LoggingIn aktivitas membatalkan upaya masuk dan menampilkan pesan kesalahan yang ditentukan dalam InstructionText properti .

<%@ 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">
// This custom Login control checks the user name 
// entered by the user is a valid email address
class CustomLogin : Login
{
    bool IsValidEmail(string strIn)
    {
        // Return true if strIn is in valid email format.
        return Regex.IsMatch(strIn, @"^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$"); 
    }

    override protected void OnLoggingIn(System.Web.UI.WebControls.LoginCancelEventArgs e)
    {
        if (!IsValidEmail(UserName)) 
        {
            InstructionText = "You must enter a valid email address.";
            e.Cancel = true;
        }
        else 
        {
            InstructionText = String.Empty;
        }
    }
}

    // Add the custom login control to the page.
    void Page_Load(object sender, EventArgs e) 
    {
        CustomLogin loginControl = new CustomLogin();
        loginControl.ID = "loginControl";
        Placeholder1.Controls.Add(loginControl);
    }

</script>
<html xmlns="http://www.w3.org/1999/xhtml" >
    <head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
        <form id="Form1" runat="server">
            <asp:placeholder id="Placeholder1" runat="server"></asp:placeholder>
        </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">
    ' This custom Login control checks the user name
    ' entered by the user is a valid email address.
    Class CustomLogin
        Inherits Login
        
        Function IsValidEmail(ByVal strIn As String) As Boolean
            ' Return true if strIn is in valid email format.
            Return Regex.IsMatch(strIn, ("^([\w-\.]+)@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.)|(([\w-]+\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\]?)$"))
        End Function

        Overrides Protected Sub OnLoggingIn(ByVal e As System.Web.UI.WebControls.LoginCancelEventArgs)
            If Not IsValidEmail(UserName) Then
                InstructionText = "You must enter a valid email address."
                e.Cancel = True
            Else
                InstructionText = String.Empty
            End If
        End Sub
    End Class
    
    ' Add the custom login control to the page.
    Sub Page_Load(ByVal sender As Object, ByVal e As EventArgs)
        Dim loginControl As New CustomLogin

        loginControl.ID = "loginControl"

        PlaceHolder1.Controls.Add(loginControl)
    End Sub
</script>

<html xmlns="http://www.w3.org/1999/xhtml" >
<head runat="server">
    <title>ASP.NET Example</title>
</head>
<body>
<form id="Form1" runat="server">
    <asp:placeholder id="Placeholder1" runat="Server"></asp:placeholder>
</form>
</body>
</html>

Contoh kode berikut menunjukkan bagaimana Anda dapat memperluas Login kontrol. Kontrol CustomLogin ini mencakup DropDownList kontrol yang memungkinkan pengguna memilih penyedia keanggotaan mana yang diautentikasi. (Penyedia ini dikonfigurasi dalam Web.config.) OnLoggingIn Dalam metode , MembershipProvider properti diatur ke nilai kontrol yang DropDownList dipilih.

Penting

Contoh ini berisi kotak teks yang menerima input pengguna, yang merupakan potensi ancaman keamanan. Secara default, ASP.NET halaman Web memvalidasi bahwa input pengguna tidak menyertakan elemen skrip atau HTML. Untuk informasi selengkapnya, lihat Gambaran Umum Eksploitasi Skrip.

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

namespace Samples.AspNet.Controls
{
    public sealed class CustomLogin : Login
    {
        public CustomLogin() { }
        
        protected override void OnLoggingIn(LoginCancelEventArgs e)
        {
            // Set the Membership provider for the Login control from a DropDownList.
            DropDownList list = (DropDownList)this.FindControl("domain");
            this.MembershipProvider = list.SelectedValue;
            base.OnLoggingIn(e);
        }
        
        protected override void CreateChildControls()
        {
            LayoutTemplate = new MyTemplate();
            base.CreateChildControls();
        }
    }
    
    // A Template that contains the child controls.
    public class MyTemplate : ITemplate
    {
        void ITemplate.InstantiateIn(Control container)
        {
            // A TextBox for the user name.
            TextBox username = new TextBox();
            username.ID = "username";
            
            // A TextBox for the password.
            TextBox password = new TextBox();
            password.ID = "password";
            
            // A CheckBox to remember the user on subsequent visits.
            CheckBox remember = new CheckBox();
            remember.ID = "RememberMe";
            remember.Text = "Don't forget me!";
            
            // Failure Text.
            Literal failure = new Literal();
            failure.ID = "FailureText";
            
            // A DropDownList to choose the Membership provider.
            DropDownList domain = new DropDownList();
            domain.ID = "Domain";
            domain.Items.Add(new ListItem("SqlMembers"));
            domain.Items.Add(new ListItem("SqlMembers2"));
            
            // A Button to log in.
            Button submit = new Button();
            submit.CommandName = "login";
            submit.Text = "LOGIN";

            container.Controls.Add(new LiteralControl("UserName:"));
            container.Controls.Add(username);
            container.Controls.Add(new LiteralControl("<br>Password:"));
            container.Controls.Add(password);
            container.Controls.Add(new LiteralControl("<br>"));
            container.Controls.Add(remember);
            container.Controls.Add(new LiteralControl("<br>Domain:"));
            container.Controls.Add(domain);
            container.Controls.Add(new LiteralControl("<br>"));
            container.Controls.Add(failure);
            container.Controls.Add(new LiteralControl("<br>"));
            container.Controls.Add(submit);
        }
    }    
}

Imports System.Data
Imports System.Configuration
Imports System.Web
Imports System.Web.Security
Imports System.Web.UI
Imports System.Web.UI.WebControls
Imports System.Web.UI.WebControls.WebParts
Imports System.Web.UI.HtmlControls

Namespace Samples.AspNet.Controls

    NotInheritable Public Class CustomLogin
        Inherits Login

        Public Sub New() 
        End Sub

        Protected Overrides Sub OnLoggingIn(ByVal e As LoginCancelEventArgs) 

            ' Set the Membership provider for the Login control from a DropDownList.
            Dim list As DropDownList = CType(Me.FindControl("domain"), DropDownList)
            Me.MembershipProvider = list.SelectedValue
            MyBase.OnLoggingIn(e)

        End Sub


        Protected Overrides Sub CreateChildControls() 

            LayoutTemplate = New MyTemplate()
            MyBase.CreateChildControls()

        End Sub
    End Class

    ' A Template that contains the child controls.
    Public Class MyTemplate
        Implements ITemplate

        Sub InstantiateIn(ByVal container As Control)  Implements ITemplate.InstantiateIn
            ' A TextBox for the user name.
            Dim username As New TextBox()
            username.ID = "username"

            ' A TextBox for the password.
            Dim password As New TextBox()
            password.ID = "password"

            ' A CheckBox to remember the user on subsequent visits.
            Dim remember As New CheckBox()
            remember.ID = "RememberMe"
            remember.Text = "Don't forget me!"

            ' Failure Text.
            Dim failure As New Literal()
            failure.ID = "FailureText"

            ' A DropDownList to choose the Membership provider.
            Dim domain As New DropDownList()
            domain.ID = "Domain"
            domain.Items.Add(New ListItem("SqlMembers"))
            domain.Items.Add(New ListItem("SqlMembers2"))

            ' A Button to log in.
            Dim submit As New Button()
            submit.CommandName = "login"
            submit.Text = "LOGIN"

            container.Controls.Add(New LiteralControl("UserName:"))
            container.Controls.Add(username)
            container.Controls.Add(New LiteralControl("<br>Password:"))
            container.Controls.Add(password)
            container.Controls.Add(New LiteralControl("<br>"))
            container.Controls.Add(remember)
            container.Controls.Add(New LiteralControl("<br>Domain:"))
            container.Controls.Add(domain)
            container.Controls.Add(New LiteralControl("<br>"))
            container.Controls.Add(failure)
            container.Controls.Add(New LiteralControl("<br>"))
            container.Controls.Add(submit)

        End Sub
    End Class
End Namespace

Keterangan

Metode ini OnLoggingIn meningkatkan LoggingIn peristiwa. Gunakan peristiwa untuk LoggingIn melakukan pemrosesan apa pun yang Anda butuhkan sebelum mengautentikasi pengguna atau untuk melakukan validasi kustom.

Menaikkan peristiwa memanggil penanganan aktivitas melalui delegasi. Untuk informasi selengkapnya, lihat Menangani dan Meningkatkan Peristiwa.

Metode ini OnLoggingIn juga memungkinkan kelas turunan untuk menangani peristiwa tanpa melampirkan delegasi. Ini adalah teknik yang disukai untuk menangani peristiwa di kelas turunan.

Catatan Bagi Inheritor

Saat mengambil alih di kelas turunan OnLoggingIn(LoginCancelEventArgs) , pastikan untuk memanggil metode kelas OnLoggingIn(LoginCancelEventArgs) dasar sehingga delegasi terdaftar menerima peristiwa tersebut.

Berlaku untuk

Lihat juga

ASP.NET Gambaran Umum Kontrol Login

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