在Web应用程序中，提供“记住”功能可以让用户在下次访问时无需重新输入用户名和密码，从而提高用户体验。本文将介绍如何在VB.Net和C#.Net中实现这一功能。
“记住”功能通常通过在用户的浏览器上存储一个cookie来实现。当用户勾选“记住”复选框并登录时，应用程序会创建一个cookie，其中包含用户的用户名和密码。在用户下次访问网站时，应用程序会检查这个cookie，如果存在，则自动填充用户名和密码，实现自动登录。
实现“记住”功能需要以下几个步骤：
以下是使用VB.Net实现“记住”功能的示例代码：
Partial Class _Default
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If Not IsPostBack Then
If Request.Browser.Cookies Then
If Request.Cookies("PBLOGIN") IsNot Nothing Then
Me.VerifyLogin(Request.Cookies("PBLOGIN")("UNAME").ToString(), Request.Cookies("PBLOGIN")("UPASS").ToString())
End If
End If
End If
End Sub
Protected Sub BtLogin_Click(ByVal sender As Object, ByVal e As System.EventArgs)
If Me.CbRememberMe.Checked Then
If Request.Browser.Cookies Then
If Request.Cookies("PBLOGIN") Is Nothing Then
Response.Cookies("PBLOGIN").Expires = DateTime.Now.AddDays(30)
Response.Cookies("PBLOGIN").Item("UNAME") = Me.TbUserName.Text
Response.Cookies("PBLOGIN").Item("UPASS") = Me.TbPassword.Text
Else
Response.Cookies("PBLOGIN").Item("UNAME") = Me.TbUserName.Text
Response.Cookies("PBLOGIN").Item("UPASS") = Me.TbPassword.Text
End If
End If
End If
Me.VerifyLogin(Me.TbUserName.Text, Me.TbPassword.Text)
End Sub
Protected Sub VerifyLogin(ByVal UserName As String, ByVal Password As String)
Try
'If login credentials are correct
'Redirect to the user page
'else
'prompt user for invalid password
'end if
Catch ex As System.Exception
Response.Write(ex.Message)
End Try
End Sub
Protected Sub lbSignout_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles lbSignout.Click
If Request.Cookies("PBLOGIN") IsNot Nothing Then
Response.Cookies("PBLOGIN").Expires = DateTime.Now.AddDays(-30)
End If
End Sub
End Class
以下是使用C#.Net实现“记住”功能的示例代码：
partial class _Default : System.Web.UI.Page
{
protected void Page_Load(object sender, System.EventArgs e)
{
if (!IsPostBack)
{
if (Request.Browser.Cookies)
{
if (Request.Cookies["PBLOGIN"] != null)
{
this.VerifyLogin(Request.Cookies["PBLOGIN"]["UNAME"].ToString(), Request.Cookies["PBLOGIN"]["UPASS"].ToString());
}
}
}
}
protected void BtLogin_Click(object sender, System.EventArgs e)
{
if (this.CbRememberMe.Checked)
{
if (Request.Browser.Cookies)
{
if (Request.Cookies["PBLOGIN"] == null)
{
Response.Cookies["PBLOGIN"].Expires = DateTime.Now.AddDays(30);
Response.Cookies["PBLOGIN"]["UNAME"] = this.TbUserName.Text;
Response.Cookies["PBLOGIN"]["UPASS"] = this.TbPassword.Text;
}
else
{
Response.Cookies["PBLOGIN"]["UNAME"] = this.TbUserName.Text;
Response.Cookies["PBLOGIN"]["UPASS"] = this.TbPassword.Text;
}
}
}
this.VerifyLogin(this.TbUserName.Text, this.TbPassword.Text);
}
protected void VerifyLogin(string UserName, string Password)
{
try
{
//If login credentials are correct
//Redirect to the user page
//else
//prompt user for invalid password
//end if
}
catch (System.Exception ex)
{
Response.Write(ex.Message);
}
}
protected void lbSignout_Click(object sender, System.EventArgs e)
{
if (Request.Cookies["PBLOGIN"] != null)
{
Response.Cookies["PBLOGIN"].Expires = DateTime.Now.AddDays(-30);
}
}
}