我创建了一个在线考试系统。它一次只能运行一个用户。但是，当多个用户登录时会出现问题。
每次测试都有20个问题。如果只有一个用户正在进行测试，那么它可以正常工作。用户可以完成所有20个问题。现在另一个用户同时登录。该用户没有收到所有20个问题。说User1已完成12个问题。 User2只会得到8个问题。
假设有User1，User2，User3同时登录。 User1做了8个问题，User2做了6个问题，User3也做了8个问题。他们都会在没有完成20个问题的情况下到达结果页面。这意味着，如果有20个用户，他们只会得到1个问题，而不是20个。有人可以帮忙吗？
try
{
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["hasexaminationConnectionString"].ConnectionString);
SqlCommand cmd = new SqlCommand();
SqlDataReader dr;
cmd.Connection = con;
cmd.CommandText = "select * from tblregister where Name=@Name and EMail=@EMail";
cmd.Parameters.Add("@Name", SqlDbType.VarChar).Value = TxtStName.Text;
cmd.Parameters.Add("@EMail", SqlDbType.VarChar).Value = TxtStudentID.Text;
//cmd.Parameters.Add("@Flag", SqlDbType.Int).Value = Convert.ToInt32(HiddenField1.Value);
con.Open();
dr = cmd.ExecuteReader();
if (dr.Read())
{
FormsAuthentication.RedirectFromLoginPage(TxtStName.Text, false);
Session["Name"] = TxtStName.Text;
Session["EMail"] = TxtStudentID.Text;
Response.Redirect("TestHome.aspx");
}
else
{
Label1.Visible = true;
Label1.Text = "UserName or Password is Required/Incorrect.";
}
}
catch
{ }
}
下一页：
protected void Page_Load(object sender, EventArgs e)
{
mob = HttpContext.Current.Session["Name"].ToString();
number = HttpContext.Current.Session["EMail"].ToString();
//Response.Cache.SetCacheability(HttpCacheability.NoCache);
if (Session["mob"] == null & Session["number"] == null)
//Response.Redirect("Home.aspx");
if (!IsPostBack)
{
DataSet TestList = getTestList("GetTestList");
DataList1.DataSource = TestList;
DataList1.DataBind();
}
}
public DataSet getTestList(string procedurename)
{
using (DataSet QuestionSet = new DataSet())
{
using (DataTable QTable = new DataTable())
{
QTable.Columns.Add("TESTNAME");
QTable.Columns.Add("TESTNUMBER");
DataTable dt;
cmd.Connection = con;
cmd.CommandText = "select * from testnumber";
using (Da = new SqlDataAdapter(cmd))
{
con.Open();
dt = new DataTable();
Da.Fill(dt);
if (dt.Rows.Count > 0)
{
DataRow dr;
for (int i = 0; i < dt.Rows.Count; i++)
{
dr = QTable.NewRow();
dr[0] = dt.Rows[i]["testname"].ToString();
dr[1] = dt.Rows[i]["testnumber"].ToString();
QTable.Rows.Add(dr);
}
}
}
QuestionSet.Tables.Add(QTable);
return QuestionSet;
}
}
}
protected void LinkButton_Click(object sender, CommandEventArgs e)
{
string name = e.CommandArgument.ToString();
Response.Redirect("TakeTest1.aspx?testno=" + e.CommandArgument.ToString());
}
下：
protected void Page_Load(object sender, EventArgs e)
{
//UserName = Session["UserName"].ToString();
//Password = Session["Password"].ToString();
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["hasexaminationConnectionString"].ConnectionString);
SqlCommand cmd = new SqlCommand();
SqlDataReader dr;
cmd.Connection = con;
cmd.CommandText = "select username,password,flag from tblcollegeuser where username='" + UserName + "'and password='" + Password + "'";
con.Open();
dr = cmd.ExecuteReader();
if (dr.Read())
{
HiddenField1.Value = dr["Flag"].ToString();
if (HiddenField1.Value.ToString() == "0")
{
//Response.Write("<script>alert('Your Session Timer has Expired! We are Sorry!')</script>");
Response.Redirect("Result.aspx");
}
}
if (HttpContext.Current.Session["Name"] == null && HttpContext.Current.Session["EMail"] == null)
{
Response.Write("<script>alert('Your Session Timer has Expired! We are Sorry!')</script>");
Response.Redirect("default.aspx");
}
if (!IsPostBack)
{
this.timerStartValue = long.Parse(ConfigurationManager.AppSettings["Delay"].ToString());
this.TimerInterval = 500;
tno = Request.QueryString["testno"].ToString();
//string query = "select * from questions where tnumber='" + tno + "'";
Questions = GetDataSet(tno);
totalQs = GetCount(tno);
LoadQuestion();
DataSet questions = new DataSet("Questions");
questions.Tables.Add();
}
}
protected override void OnPreRender(EventArgs e)
{
base.OnPreRender(e);
string strDisAbleBackButton;
strDisAbleBackButton = "";
ClientScript.RegisterClientScriptBlock(this.Page.GetType(), "clientScript", strDisAbleBackButton);
}
public DataSet GetDataSet(string query)
{
using (DataSet QuestionSet = new DataSet())
{
using (DataTable QTable = new DataTable())
{
QTable.Columns.Add("ROW_NUMBER");
QTable.Columns.Add("QuestionNo");
QTable.Columns.Add("Tname");
QTable.Columns.Add("Tnumber");
QTable.Columns.Add("question");
QTable.Columns.Add("ans1");
QTable.Columns.Add("ans2");
QTable.Columns.Add("ans3");
QTable.Columns.Add("ans4");
DataTable dt;
using (cmd.Connection = con)
{
//cmd.CommandText = " SELECT * FROM test ORDER BY CHECKSUM(NEWID()) where tnumber='" + query + "'";
cmd.CommandText = " SELECT * FROM test WHERE tnumber='" + query + "' ORDER BY CHECKSUM(NEWID()) ";
//cmd.Parameters.AddWithValue("@cse", query);
Da = new SqlDataAdapter(cmd);
con.Open();
dt = new DataTable();
Da.Fill(dt);
if (dt.Rows.Count > 0)
{
DataRow dr;
for (int i = 0; i < dt.Rows.Count; i++)
{
dr = QTable.NewRow();
dr[0] = dt.Rows[i]["id"].ToString();
dr[1] = "Qno" + dt.Rows[i]["Qno"].ToString();
dr[2] = dt.Rows[i]["tname"].ToString();
dr[3] = dt.Rows[i]["tnumber"].ToString();
dr[4] = dt.Rows[i]["quation"].ToString();
dr[5] = dt.Rows[i]["ans1"].ToString();
dr[6] = dt.Rows[i]["ans2"].ToString();
dr[7] = dt.Rows[i]["ans3"].ToString();
dr[8] = dt.Rows[i]["ans4"].ToString();
QTable.Rows.Add(dr);
}
}
}
QuestionSet.Tables.Add(QTable);
return QuestionSet;
}
}
}
public Int32 GetCount(string tno)
{
return 10;
}
void Page_PreRender(object sender, EventArgs e)
{
StringBuilder bldr = new StringBuilder();
bldr.AppendFormat("var Timer = new myTimer({0},{1},'{2}','timerData');", this.timerStartValue, this.TimerInterval, this.lblTimerCount.ClientID);
bldr.Append("Timer.go()");
ClientScript.RegisterStartupScript(this.GetType(), "TimerScript", bldr.ToString(), true);
ClientScript.RegisterHiddenField("timerData", timerStartValue.ToString());
}
void Page_PreInit(object sender, EventArgs e)
{
string timerVal = Request.Form["timerData"];
if (timerVal != null || timerVal == "")
{
timerVal = timerVal.Replace(",", String.Empty);
timerStartValue = long.Parse(timerVal);
}
}
private Int32 TimerInterval
{
get
{
object o = ViewState["timerInterval"];
if (o != null) { return Int32.Parse(o.ToString()); }
return 50;
}
set { ViewState["timerInterval"] = value; }
}
void RedirectToResults()
{
Response.Redirect("Results.aspx");
}
protected void LoadQuestion()
{
if (Questions.Tables[0].Rows.Count > 0)
{
//Load Question;
DataRow DR = Questions.Tables[0].Rows[0];
//Question.Text = DR[0].ToString() + " of " + 20;
//Question.Text = (i + 1).ToString() + " of " + 20;
sno = DR[1].ToString();
TestName.Text = DR[2].ToString();
TestNo.Text = DR[3].ToString();
Questionlbl.Text = DR[4].ToString();
rbtnAns.Items.Clear();
rbtnAns.Items.Add(DR[5].ToString());
rbtnAns.Items.Add(DR[6].ToString());
rbtnAns.Items.Add(DR[7].ToString());
rbtnAns.Items.Add(DR[8].ToString());
Questions.Tables[0].Rows.Remove(DR);
if (Questionlbl.Text.Equals(totalQs.ToString()))
{
IsLastQs = true;
}
}
else
{
//End Of File;
//Response.Write("<script>alert('Thanks For Your Presence! You Can Leave Now.')</script>");
//Session.Abandon();
Session["raj"] = Questions;
RedirectToResults();
}
}
protected void Button1_Click(object sender, EventArgs e)
{
try
{
//Write your code here to save the question
//Displays the Next Question
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["hasexaminationConnectionString"].ConnectionString);
SqlCommand cmd = new SqlCommand("insert into testdisplay Values ('" + sno + "','" + Session["Name"] + "','" + Session["EMail"] + "','" + Questionlbl.Text + "','" + rbtnAns.SelectedItem.Text + "')", con);
con.Open();
cmd.ExecuteNonQuery();
con.Close();
LoadQuestion();
}
catch (Exception ex)
{
Response.Write("<script>alert(''" + ex.Message + "'')</script>");
}
}
protected void Button2_Click(object sender, EventArgs e)
{
//When Skip Button is pressed it loads the next question
LoadQuestion();
}
和结果页面：
protected void Page_Load(object sender, EventArgs e)
{
l = Session["Name"].ToString();
m = Session["EMail"].ToString();
SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["hasexaminationConnectionString"].ConnectionString);
SqlCommand cmd = new SqlCommand("select tnumber,quation,ans1,ans2,ans3,ans4,ans from test left join testdisplay on (test.ans= testdisplay.answ and test.quation= testdisplay.quations) where UserName='" + Session["Name"] + "' and Password='" + Session["EMail"] + "'", con);
con.Open();
SqlDataAdapter adp = new SqlDataAdapter(cmd);
adp.Fill(dt);
con.Close();
{
int to = 20;
GridView1.DataSource = dt;
GridView1.DataBind();
int marks = GridView1.Rows.Count;
Label1.Text = Convert.ToInt32(GridView1.Rows.Count).ToString();
decimal total = Convert.ToDecimal((double)marks / (double)20) * 100;
lbltotal.Text = total.ToString();
}
}
public void bind()
{
// Write your code to get the summary of the result and display it
}
protected void Button1_Click(object sender, EventArgs e)
{
//Response.Redirect("Home.aspx");
string uniqueCode = string.Empty;
//SqlDataReader dr;
try
{
DataSet ds = new DataSet();
using (SqlConnection con = new SqlConnection(ConfigurationManager.ConnectionStrings["hasexaminationConnectionString"].ConnectionString))
{
con.Open();
SqlCommand cmd = new SqlCommand("SELECT Name,EMail FROM tblregister Where EMail= '" + txtEmail.Text.Trim() + "'", con);
SqlDataAdapter da = new SqlDataAdapter(cmd);
da.Fill(ds);
////}
if (Page.IsValid)
{
//GridView1.RenderControl(hw);
const string SERVER = "relay-hosting.secureserver.net";
MailMessage oMail = new MailMessage();
oMail.From = new MailAddress("contact@dssgroups.com");
oMail.To.Add(new MailAddress(txtEmail.Text.Trim()));
oMail.Subject = "Your Test Details";
oMail.IsBodyHtml = true; // enumeration
oMail.Priority = MailPriority.High; // enumeration
oMail.Body = "Hi, <br/><b>Please check your Test Details:</b><br/><br/>Your Marks Percentage: " + lbltotal.Text+" % "+"<br/>For any query contact "+" http://dssgroups.com";
SmtpClient sC = new SmtpClient(SERVER);
sC.EnableSsl = false;
ContentType contentType = new ContentType();
contentType.MediaType = MediaTypeNames.Application.Octet;
contentType.Name = "xml.xml";
sC.Send(oMail);
oMail = null; // free up resources
lblMessage.ForeColor = System.Drawing.Color.DarkKhaki;
lblMessage.Text = "EMail Sent";
ScriptManager.RegisterStartupScript(this, GetType(), "showalert", "alert('EMail Sent');", true);
}
else
{
lblMessage.Text = "The Email you entered not exists.";
}
}
//}
}
catch (Exception ex)
{
Console.WriteLine("{0} Exception caught.", ex);
}
}
protected void Button2_Click(object sender, EventArgs e)
{
Session.Clear();
Session.Abandon();
Response.Redirect("default.aspx");
}