请帮助我实际上我希望如果用户登录然后用户可以检查
课程信息，否则它会定向到登录页面然后返回到 courseinfo
页面但是登录后它会给出错误
我的代码是aspx
<%@ Page Language="C#" MasterPageFile="~/Secret for Management/MasterPage.master"
AutoEventWireup="true" CodeFile="Course_info.aspx.cs" Inherits="Secret_Course_info"
Title="Untitled Page" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="Server">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-2" />
<meta http-equiv="Content-Language" content="English" />
<meta name="Author" content="MominaNisar ()" />
<meta name="MominaNisar" content="index,follow" />
<meta name="Description" content="CENTER MANAGEMENT" />
<meta name="Keywords" content="CENTER ,MANAGEMENT" />
<link rel="stylesheet" type="text/css" href="../style.css" />
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<li><a href="../Secret for all user/Default.aspx" accesskey="c"><span
class="key">H</span>ome</a></li>
<li><a href="../Secret for all user/Management.aspx" accesskey="g"><span class="key">
M</span>anagement</a></li>
<li><a href="../Secret for all user/student.aspx" accesskey="s"><span
class="key">S</span>tudent</a></li>
<li class="active"><span class="key">C</span>ourse</li>
<li><a href="../Secret for all user/Exam_schedule.aspx" accesskey="x">Exam<span
class="key">
S</span>chedule</a></li>
<li><a href="../Secret for all user/Notice_Board.aspx" accesskey="n"><span class="key">
N</span>otice Board</a></li>
<li><a href="../Secret for all user/Visiter_info.aspx" accesskey="n"><span class="key">
V</span>isitor</a></li>
</asp:Content>
<asp:Content ID="Content3" ContentPlaceHolderID="Menu_left" runat="Server">
<li><a href="../Secret for all user/Course_of_Management.aspx" accesskey="n"><span
class="key">M</span>anagement</a></li>
<li><a href="../Secret for all user/Course_of_Computer_science.aspx" accesskey="f">
<span
class="key">C</span>omputer Science</a></li>
<li><a href="../Secret for all user/Course_of_Other.aspx" accesskey="F"><span
class="key">
O</span>ther</a></li>
</asp:Content>
<asp:Content ID="Content4" ContentPlaceHolderID="Leftcol610" runat="Server">
<h3>
Courses Info
</h3>
<asp:UpdatePanel ID="up1" runat="server">
<ContentTemplate>
<asp:Panel ID="pn" DefaultButton="btnSubmit" runat="server">
<table align="center">
<tr>
<td colspan="3">
</td>
</tr>
<tr>
<td class="active">
</td>
<td class="active">
Course Name :
</td>
<td>
<asp:TextBox ID="Course_Name" runat="server" />
<asp:RequiredFieldValidator ID="RequiredFieldValidator1" runat="server"
SetFocusOnError="True" ControlToValidate="Course_Name">*
</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td class="active">
</td>
<td class="active">
Course Duration :
</td>
<td>
<asp:TextBox ID="Course_Duration" runat="server" />
<asp:RequiredFieldValidator ID="RequiredFieldValidator2" runat="server"
SetFocusOnError="True" ControlToValidate="Course_Duration">*
</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td class="active">
</td>
<td class="active">
Course Qualification :
</td>
<td>
<asp:TextBox ID="Course_Qualification" runat="server" />
<asp:RequiredFieldValidator ID="RequiredFieldValidator3" runat="server"
SetFocusOnError="True" ControlToValidate="Course_Qualification">*
</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td class="active">
</td>
<td class="active">
Course Total Fees :
</td>
<td>
<asp:TextBox ID="Course_Total_Fees" runat="server" />
<asp:RequiredFieldValidator ID="RequiredFieldValidator4" runat="server"
SetFocusOnError="True" ControlToValidate="Course_Total_Fees">*
</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td class="active">
</td>
<td class="active">
Course Fees Method :
</td>
<td>
<asp:TextBox ID="Course_Fees_Method" runat="server" />
<asp:RequiredFieldValidator ID="RequiredFieldValidator5" runat="server"
SetFocusOnError="True" ControlToValidate="Course_Fees_Method">*
</asp:RequiredFieldValidator>
</td>
</tr>
<tr>
<td class="active" colspan="3">
<asp:Label ID="lblerror" CssClass="popuptitle" Style="color: Red" runat="server"
Width="465px" Visible="False" />
</td>
</tr>
<tr>
<td class="active" colspan="3" align="center">
<asp:Button Text="SUBMIT" ID="btnSubmit" runat="server"
onclick="btnSubmit_Click" Visible="False" />
</td>
</tr>
</table>
</asp:Panel>
</ContentTemplate>
</asp:UpdatePanel>
</asp:Content>
aspx.cs
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
public partial class Secret_Course_info : System.Web.UI.Page
{
SqlConnection con;
SqlCommand cmd;
SqlDataReader rea;
protected void Page_Load(object sender, EventArgs e)
{
if (Request.Cookies["UserName"] != null)
{
if (Context.User.Identity.Name.ToString() == "admin")
{
btnSubmit.Visible = true;
}
else
{
btnSubmit.Visible = false;
lblerror.Visible = true;
lblerror.Text = "::This Page Only For Administrator::";
}
}
else
{
Response.Cookies["path"].Value = Request.Url.AbsolutePath.ToString();
/* now after login i want that it reverts to the page but it gives the error object reference is not set to instance of the type*/
Response.Redirect("Login.aspx");
}
}
protected void btnSubmit_Click(object sender, EventArgs e)
{
int total;
total = 0;
String strcon = "Data Source=localhost;Initial
Catalog=Student_BioData;user=aaa;pwd=123;";
string strsql = "select * from Courses ";
con = new SqlConnection(strcon);
cmd = new SqlCommand();
try
{
con.Open();
cmd.Connection = con;
cmd.CommandText = strsql;
rea = cmd.ExecuteReader();
while (rea.Read()) { total++; }
}
catch (SqlException ex) { lblerror.Text = ex.Message.ToString(); }
total += 1;
try
{
strsql = "Insert into Courses values('"+
Course_Name.Text.Trim()+ "','" +
Course_Duration.Text.Trim() + "','" +
Course_Qualification.Text.Trim() + "','" +
Course_Total_Fees.Text.Trim() + "','" +
Course_Fees_Method.Text.Trim()+ "')";
con = new SqlConnection(strcon);
cmd = new SqlCommand();
con.Open();
cmd.Connection = con;
cmd.CommandText = strsql;
cmd.ExecuteNonQuery();
lblerror.Visible = true;
lblerror.Text = " Data Save In Courses info ";
}
catch (SqlException ex) { lblerror.Text = ex.Message.ToString(); }
}
}
stack trace
[NullReferenceException: Object reference not set to an instance of an object.]
Loginpage.btnLogIn_Click(Object sender, EventArgs e) in d:\Momina\installed
setup\Center Management\Center Management\Login.aspx.cs:53
System.Web.UI.WebControls.Button.OnClick(EventArgs e) +118
System.Web.UI.WebControls.Button.RaisePostBackEvent(String eventArgument) +112
System.Web.UI.WebControls.Button.System.Web.UI.IPostBackEventHandler
.RaisePostBackEvent(String eventArgument) +10
System.Web.UI.Page.RaisePostBackEvent(IPostBackEventHandler sourceControl, String
eventArgument) +13
System.Web.UI.Page.RaisePostBackEvent(NameValueCollection postData) +36
System.Web.UI.Page.ProcessRequestMain(Boolean includeStagesBeforeAsyncPoint,
Boolean includeStagesAfterAsyncPoint) +5563
it gives error like
//Response.Redirect("UpdateProfile.aspx");
Line 52: Response.Cookies["UserName"].Value = txtUserName.Text;
Line 53: Response.Redirect(Request.Cookies["path"].Value.ToString());//herecomes error
Line 54: }
Line 55: else
login.aspx
<%@ Page Language="C#" MasterPageFile="~/MasterPage.master" AutoEventWireup="true"
CodeFile="Login.aspx.cs" Inherits="Loginpage" Title="Loginpage" %>
<asp:Content ID="Content1" ContentPlaceHolderID="head" runat="Server">
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-2" />
<meta http-equiv="Content-Language" content="English" />
<meta name="Author" content="Momina Nisar " />
<meta name="Momina Nisar " content="index,follow" />
<meta name="Description" content="STUDENT MANAGEMENT SYSTEM" />
<meta name="Keywords" content="STUDENT,MANAGEMENT" />
<link rel="stylesheet" type="text/css" href="style.css" />
</asp:Content>
<asp:Content ID="Content2" ContentPlaceHolderID="ContentPlaceHolder1" runat="Server">
<li><a href="Default.aspx" accesskey="h"><span class="key">H</span>ome</a></li>
<li><a href="Management.aspx" accesskey="g"><span class="key">M</span>anagement</a>
</li>
<li><a href="student.aspx" accesskey="s"><span class="key">S</span>tudent</a></li>
<li><a href="Course_Infor.aspx" accesskey="c"><span class="key">C</span>ourse</a></li>
<li><a href="Exam_schedule.aspx" accesskey="x">Exam<span class="key">
S</span>chedule</a></li>
<li><a href="Notice_Board.aspx" accesskey="n"><span class="key">N</span>otice Board</a>
</li>
<li><a href="Visiter_info.aspx" accesskey="n"><span class="key">V</span>isitor</a></li>
</asp:Content>
<asp:Content ID="Content3" ContentPlaceHolderID="Menu_left" runat="Server">
<li><a href="Login.aspx" accesskey="l"><span class="key">L</span>ogin</a></li>
<li><a href="Contas_us.aspx" accesskey="u"><span class="key">C</span>ontact Us</a></li>
<li><a href="Feedback.aspx" accesskey="f">Feed<span class="key">B</span>ack</a></li>
</asp:Content>
<asp:Content ID="Content4" ContentPlaceHolderID="Leftcol610" runat="Server">
<fieldset>
<legend>Login</legend>
<div class='container'>
<asp:Label ID="Name" runat="server" Text="UserName:" CssClass="lbl"/>
<br/>
<asp:TextBox ID="txtUserName" runat="server" Height="22px"/>
<asp:RequiredFieldValidator ID="RV1" runat="server"
ControlToValidate="txtUserName"
ErrorMessage="Please Enter User Name"
SetFocusOnError="True">*
</asp:RequiredFieldValidator><br />
</div>
<div class='container'>
<asp:Label ID="lblPwd" runat="server" Text="Password:" CssClass="lbl"/>
<br/>
<asp:TextBox ID="txtPwd" runat="server" TextMode="Password"
CssClass="pwd" Height="22px"/>
<asp:RequiredFieldValidator ID="RV2" runat="server"
ControlToValidate="txtPwd"
ErrorMessage="Your Password"
SetFocusOnError="True">*
</asp:RequiredFieldValidator><br />
</div>
<div class='container'>
<asp:Button ID="btnLogIn" runat="server" Text="Sign In"
onclick="btnLogIn_Click"/>
</div>
<div class='container'>
<asp:HyperLink ID="HyperLink1" runat="server"
NavigateUrl="~/ForgotPassword.aspx">Forgot Password ?</asp:HyperLink>
<br/>
</div>
<div class='short_explanation'>New User ?
<asp:HyperLink ID="HyperLink2" runat="server"
NavigateUrl="~/Createuser.aspx">SignUp !</asp:HyperLink></div>
<asp:ValidationSummary ID="ValidationSummary1"
runat="server" CssClass="error"/>
<br /><br />
<asp:Label ID="lblMsg" runat="server" Text="" CssClass="lbl"/>
</fieldset>
</asp:Content>
login.aspx.cs
using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Linq;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.HtmlControls;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Xml.Linq;
using System.Data.SqlClient;
using System.Net;
using System.Net.Mail;
public partial class Loginpage : System.Web.UI.Page
{
protected void Page_Load(object sender, EventArgs e)
{
//Login1.Focus();
}
protected void btnLogIn_Click(object sender, EventArgs e)
{
String strCon = "Data Source=localhost;Initial
Catalog=Student_BioData;user=aaa;pwd=123;";
string strSelect = "SELECT COUNT(*) FROM integrate WHERE UserName = @UserName AND
Password = @Password";
SqlConnection con = new SqlConnection(strCon);
SqlCommand cmd = new SqlCommand();
cmd.Connection = con;
cmd.CommandType = CommandType.Text;
cmd.CommandText = strSelect;
SqlParameter username = new SqlParameter("@UserName", SqlDbType.VarChar, 50);
username.Value = txtUserName.Text.Trim().ToString();
cmd.Parameters.Add(username);
SqlParameter password = new SqlParameter("@Password", SqlDbType.VarChar, 50);
password.Value = txtPwd.Text.Trim().ToString();
cmd.Parameters.Add(password);
con.Open();
int result = (Int32)cmd.ExecuteScalar();
con.Close();
if (result >= 1)
{
Session["UserName"] = txtUserName.Text.ToString().Trim();
//Response.Redirect("UpdateProfile.aspx");
Response.Cookies["UserName"].Value = txtUserName.Text;
Response.Redirect(Request.Cookies["path"].Value.ToString());
}
else
lblMsg.Text = "Incorrect Username or Password";
}
}
请帮助我实际上我希望如果用户登录然后用户可以检查
课程信息，否则它会定向到登录页面然后返回到 courseinfo
页面但是登录后它会给出错误