Problem with SqlParameter and Request.QueryString

i've trying this code to display content from sqlserver database based on querystring, but get error like this : Parameterized Query '(@ContentID nvarchar(4000))select idcontent,title,intro_text fro' expects parameter @ContentID, which was not supplied.

what's the solution for this problem..?thanks you

code for default.aspx.cs

using System;
using System.Collections;
using System.Configuration;
using System.Data;
using System.Data.SqlClient;
using System.Web.Configuration;
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;


public partial class _Default : System.Web.UI.Page
{
    protected void Page_Load(object sender, EventArgs e)
    {
        if (!Page.IsPostBack)
        {
            PopulateMenu();
            
        }
    }
    private void PopulateMenu()
    {
        DataTable menuData = GetMenuData();
        AddTopMenuItems(menuData);
    }
    private DataTable GetMenuData()
    {
        string selectCommand = "SELECT * FROM menu_top";
        string conString = WebConfigurationManager.ConnectionStrings["MyConn"].ConnectionString;
        SqlDataAdapter dad = new SqlDataAdapter(selectCommand, conString);
        DataTable dtblCategories = new DataTable();
        dad.Fill(dtblCategories);
        return dtblCategories;
    }
    private void AddTopMenuItems(DataTable menuData)
    {
        DataView view = new DataView(menuData);
        view.RowFilter = "ParentID IS NULL";
        foreach (DataRowView row in view)
        {
            MenuItem newMenuItem = new MenuItem(row["MenuTitle"].ToString(), row["MenuId"].ToString(), null, "Default.aspx?id=" + row["contentID"].ToString());


            Menu1.Items.Add(newMenuItem);
            AddChildMenuItems(menuData, newMenuItem);
            bindDetailsView();
        }

    }

    private void AddChildMenuItems(DataTable menuData, MenuItem parentMenuItem)
    {
        DataView view = new DataView(menuData);
        view.RowFilter = "ParentID=" + parentMenuItem.Value;
        foreach (DataRowView row in view)
        {
            MenuItem newMenuItem = new MenuItem(row["MenuTitle"].ToString(), row["contentID"].ToString(), null, "Default.aspx?id=" + row["contentID"].ToString());


            parentMenuItem.ChildItems.Add(newMenuItem);

            AddChildMenuItems(menuData, newMenuItem);
        }
    }

    public void bindDetailsView()
    {
        //SqlConnection con = new SqlConnection("Data Source=STD-258E51EA446\\SQLEXPRESS;Initial Catalog=Customers;Integrated Security=True");
        //SqlCommand cmd = new SqlCommand("Select CustomerID,CustomerName,Address from Customer where CustomerID=@CustomerID", con);
        //cmd.Parameters.AddWithValue("@CustomerID", Request.QueryString["QSCustomerID"]);
        //SqlDataAdapter da = new SqlDataAdapter(cmd);
        //DataSet ds = new DataSet();
        //da.Fill(ds);
        //DetailsView1.DataSource = ds;
        //DetailsView1.DataBind();

        string strConn;
        
        strConn = WebConfigurationManager.ConnectionStrings["MyConn"].ConnectionString;
        SqlConnection Conn = new SqlConnection(strConn);
        Conn.Open();

        SqlCommand cmd = new SqlCommand("select idcontent,title,intro_text from content where idcontent=@ContentId", Conn);
        cmd.Parameters.AddWithValue("@ContentID", Request.QueryString["id"]);

        
        SqlDataAdapter da = new SqlDataAdapter(cmd);
        DataSet ds = new DataSet();
        da.Fill(ds);
        DetailsView1.DataSource = ds;
        DetailsView1.DataBind();
        //Conn.Close();
    }
}


code for default.aspx

<%@ Page Language="C#" AutoEventWireup="true"  CodeFile="Default.aspx.cs" Inherits="_Default" %>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">

<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
    <title></title>
</head>

<style type="text/css">
        .menuItem
        {
            border:Solid 1px black;
            width:100px;
            padding:2px;
            background-color:#eeeeee;
        }
        .menuItem a
        {
            color:blue;
        }
        .grid
        {
            margin-top:10px;
        }

        .grid td, .grid th
        {
            padding:10px;
        }
</style>

<body>
    <form id="form1" runat="server">
    <div>       
           <asp:Menu id="Menu1" Orientation="horizontal"
                StaticMenuItemStyle-CssClass="menuItem"
                DynamicMenuItemStyle-CssClass="menuItem"
                Runat="server" />
           
           <asp:DetailsView ID="DetailsView1" runat="server"></asp:DetailsView>
            
    
    </div>
    </form>
</body>
</html>

Re: Problem with SqlParameter and Request.QueryString

to avoid the error, you can add something like this:

if (Request.QueryString["id"] != null)

     cmd.Parameters.AddWithValue("@ContentID", Request.QueryString["id"]);

else
      cmd.Parameters.AddWithValue("@ContentID", DbNull.Value);

Re: Problem with SqlParameter and Request.QueryString

it's work properly..thanks you very much mr. rajsedhain

Re: Problem with SqlParameter and Request.QueryString

Glad, it's working now.