configuration>
 system.web>
  compilation debug="true"/>
  authentication mode="Forms">
   forms loginUrl="login.aspx" name = ".ASPXFORMSAUTH" />
  /authentication>
  authorization>
   deny users="?"/>
  /authorization>
 /system.web>
/configuration>

HTML>
HEAD>
TITLE>首页/TITLE>
script language="VB" runat="server">
 Sub Page_Load(Sender As Object, e As EventArgs)
  Message.Text = String.Format("你好，{0}", Context.User.Identity.Name)
 End Sub
 sub btnSignout_Click(Sender as Object, E as EventArgs)
  FormsAuthentication.SignOut()
  Response.Redirect("login.aspx")
 end sub
/script>
/HEAD>
BODY>
asp:label id="Message" runat="server"/>
br>
form method="post" runat="server">
 asp:button id="btnSignout" Text="退出登录" runat="server" OnClick="btnSignout_Click"/>
/form>
/BODY>
/HTML>

HEAD>
TITLE>首页/TITLE>
script lanugage="c#" runat="server">
 private void Page_Load(object sender, EventArgs e)
 {
  if (Request.IsAuthenticated)
    Response.Redirect("default.aspx");
 }
 void btnLogin_Click(Object sender, EventArgs e)
 {
  if (txtUsername.Text != null txtUsername.Text != String.Empty txtPassword.Text != null txtPassword.Text != String.Empty)
   FormsAuthentication.RedirectFromLoginPage(txtUsername.Text, true);
  else
   lblError.Text = "错误的用户名/密码";
 }
/script>
/HEAD>
BODY>
form method="post" runat="server">
 asp:Label id="lblUsername" runat="server" Text="用户名："/>
 nbsp;nbsp;nbsp;
 asp:Textbox id="txtUsername" runat="server"/>
 br>
 br>
 asp:Label id="lblPassword" runat="server" Text="密　码："/>
 nbsp;nbsp;nbsp;
 asp:Textbox id="txtPassword" runat="server" TextMode="password"/>
 br>
 asp:button id="btnLogin" runat="server" Text="登录" OnClick="btnLogin_Click" />
/form>
hr>
 br>
 asp:Label id="lblError" forecolor="red" runat="server"/>
/BODY>
/HTML>