type or namespace " " does not exist in current context :

here is the code:

default.aspx.cs

protected void btnSearch_Click(object sender, EventArgs e)

{

Panel1.Visible = true;

GridView1.DataSource = ServicesBLL.SearchBuses // here is the error

(ddlFrom.SelectedValue,

ddlTo.SelectedValue,

txtJdate.Text,

ddlBusType.SelectedValue);

GridView1.DataBind();

}

this is ServicesBLL.cs file code

using System;

using System.Collections.Generic;

using System.Data;

using System.Linq;

using System.Web;

using System.Data.DataTable;

public class ServicesBLL

{

public DataTable SearchBuses(string fromcity, string tocity, string jdate, string bustype)

{

return ServicesDAL.SearchBuses(fromcity, tocity, jdate, bustype);

}

and here is the ServiceDAL code :

public static DataTable SearchBuses(string fromcity, string tocity, string jdate, string bustype)

{

SqlConnection con = new SqlConnection(Database.ConnectionString);

try

{

con.Open();

SqlDataAdapter sda = new SqlDataAdapter("searchbuses", con);

sda.SelectCommand.Parameters.AddWithValue("@fromcity", fromcity);

sda.SelectCommand.Parameters.AddWithValue("@tocity", tocity);

sda.SelectCommand.Parameters.AddWithValue("@jdate", jdate);

sda.SelectCommand.Parameters.AddWithValue("@bustype", bustype);

sda.SelectCommand.CommandType = CommandType.StoredProcedure;

DataSet ds = new DataSet();

sda.Fill(ds, "buses");

return ds.Tables[0];

}

catch (Exception ex)

{

HttpContext.Current.Trace.Write(

"Error in SearchBuses -->" + ex.Message);

return null;

}

finally

{

con.Close();

}

all the remaining things are Fine but same error is generating

plz help