Problem In Session State

Question

Hai, I'm Using VS2010 and SQL Server 2005.
I have a problem in Session state;
//View.aspx.cs
// In this page just I store a textbox into a session variable.
protected void btnEdit_Click(object sender, EventArgs e)
        Session["rollno"] = txtRollNo.Text;
            Response.Redirect("Edit.aspx");
//Edit.aspx.cs
//In this page I retrieve the session value which is stored in previous page
       protected void Page_Load(object sender, EventArgs e)
        txtRollNo.Enabled = false;
        if (!IsPostBack)
            txtRollNo.Text = Session["rollno"].ToString();
            getdata();
 public void getdata()
        SqlConnection con = new SqlConnection("Data Source=SERVICETEAM-PC;Initial Catalog=csc;User ID=sa;Password=kavi");
        con.Open();
        SqlCommand cmd = new SqlCommand("Select * from Csc where Roll_No='" + txtRollNo.Text + "'", con);
        SqlDataReader dr = cmd.ExecuteReader();
        if (dr.Read())
            txtName.Text = dr.GetString(1).ToString();
            txtAddress.Text = dr.GetString(2).ToString();
            txtMobileNo.Text = dr.GetString(3).ToString();
            txtYesNo.Text = dr.GetString(4).ToString();
From the above code, I got an error when I press Edit button in View.aspx page.
The Error is
Description: An unhandled
exception occurred during the execution of the current web
request. Please review the stack trace for more information about the error and where it originated in the code. 
Exception Details: System.Web.HttpException: A page can have only one server-side Form
tag.
Source Error: 
An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack
trace below.
Help Me.....

Answer 1

Hai,
I'm using VS2010 and SQL Server 2005.
I have a problem in Session state.
See below is my code,
//View.aspx.cs
//Here I assign a textbox value to session
protected void btnEdit_Click(object sender, EventArgs e)
        Session["rollno"] = txtRollNo.Text;
            Response.Redirect("Edit.aspx");
//Edit.aspx.cs
//Here I assign a session value to textbox, which is stored in last page.
protected void Page_Load(object sender, EventArgs e)
        txtRollNo.Enabled = false;
        txtRollNo.Text = Session["rollno"].ToString();
        getdata();
public void getdata()
        SqlConnection con = new SqlConnection("Data Source=SERVICETEAM-PC;Initial Catalog=csc;User ID=sa;Password=kavi");
        con.Open();
        SqlCommand cmd = new SqlCommand("Select * from Csc where Roll_No='" + txtRollNo.Text + "'", con);
        SqlDataReader dr = cmd.ExecuteReader();
        if (dr.Read())
            txtName.Text = dr.GetString(1).ToString();
            txtAddress.Text = dr.GetString(2).ToString();
            txtMobileNo.Text = dr.GetString(3).ToString();
            txtYesNo.Text = dr.GetString(4).ToString();
From the above code If I the Edit button, It will show an error like