SQL data not populating in asp webform - asp.net

Question

Currently can not get any SQL data to populate the web form. When I run the report in Visual Studio preview mode, the data populates, however when running through my web app it displays nothing.
Imports System.Data.SqlClient
Public Class topvendors
Inherits System.Web.UI.Page
Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
If Not IsPostBack Then
getEntity()
' startdate.Text = DateTime.Today.ToShortDateString
End If
End Sub
Protected Sub getEntity()
Dim strConnString As String = Session("strconnection") 'ConfigurationManager.ConnectionStrings("TrialConnectionString").ConnectionString
Dim con As New SqlConnection(strConnString)
Dim cmd As New SqlCommand()
cmd.CommandType = CommandType.StoredProcedure
cmd.CommandText = "pGetProjectsByUser"
cmd.Parameters.Add("#employeeid", SqlDbType.Int).Value = Session("userid")
cmd.Parameters.Add("#reportid", SqlDbType.Int).Value = Request.QueryString("id")
cmd.Connection = con
Try
con.Open()
Dim dt As New DataTable()
Dim ds As New DataSet()
'Dim db As New SqlDataAdapter(cmd)
Dim da = New SqlDataAdapter(cmd)
da.Fill(ds)
'db.Fill(ds)
division.DataSource = ds.Tables(0)
division.DataTextField = "entityname"
division.DataValueField = "entitycode"
division.DataBind()
' If ds.Tables(0).Rows.Count > 1 Then
'divisions.Visible = False
' communities.DataSource = ds.Tables(1)
'communities.DataTextField = "Projectname"
' communities.DataValueField = "projID"
' communities.DataBind()
' Else
' divisions.Text = ds.Tables(0).Rows(0)("entityname").ToString
'division.Visible = False
' communities.DataSource = ds.Tables(1)
'communities.DataTextField = "Projectname"
'communities.DataValueField = "projID"
'communities.DataBind()
'End If
Catch ex As Exception
Throw ex
Finally
con.Close()
con.Dispose()
End Try
End Sub
Protected Sub submit_Click(ByVal sender As Object, ByVal e As EventArgs) Handles submit.Click
' Dim communities As String = Server.UrlEncode(Request.Form("communities"))
' Response.Write(communities)
' Dim removedays As Integer = Request.Form("removedays")
'getEntity()
' MsgBox(sort.SelectedValue)
Dim builder As New System.Data.SqlClient.SqlConnectionStringBuilder
builder = New SqlConnectionStringBuilder(Session("strconnection"))
Dim databasename As String = builder.InitialCatalog
Dim dataname As String
If databasename = "G3Live" Then
dataname = "2fLiveReports"
Else
dataname = "2fTestReports"
End If
Response.Redirect("http://g3reports.danryanbuilders.com/ReportServer/Pages/ReportViewer.aspx?%" + dataname + "%2fPurchasing%2flance_tutorial&rs:Format=Excel&rs%3aCommand=Render&entityid=" & division.SelectedValue & "&begindate=" + begindate.Text + "&enddate=" + enddate.Text + "&sort=" + DropdownList1.SelectedValue)
End Sub
Protected Sub Button1_Click(ByVal sender As Object, ByVal e As EventArgs) Handles Button1.Click
Dim builder As New System.Data.SqlClient.SqlConnectionStringBuilder
builder = New SqlConnectionStringBuilder(Session("strconnection"))
Dim databasename As String = builder.InitialCatalog
Dim dataname As String
If databasename = "G3Live" Then
dataname = "2fLiveReports"
Else
dataname = "2fTestReports"
End If
Response.Redirect("http://g3reports.danryanbuilders.com/ReportServer/Pages/ReportViewer.aspx?%" + dataname + "%2fPurchasing%2flance_tutorial&rs:Format=PDF&rs%3aCommand=Render&entityid=" & division.SelectedValue & "&begindate=" + begindate.Text + "&enddate=" + enddate.Text + "&sort=" + DropdownList1.SelectedValue)
End Sub
End Class

Answer 1

Note: You are storing connection string in Session, it is not recommendable. You can do but it is better you should use web.config
file to store connection string.
You can be refer this: Avoid storing connection string in session for different sql schema
For Solution I recommended
You must check the session variable prior to getting the value for the connection string.
' Check if session is null
If Not (Session("strconnection ") Is Nothing) Then
{
//
}
When it is Null or Nothing or Empty, try to retrieve the connection string again.
You need to cast session variables into their correct types, before use like
Session("strconnection")
Replace it by
Session("strconnection").toString()
And
Cast Session("userid") and Request.QueryString("id") by the help of
Integer.Parse/ Integer.TryParse
you can read this for concept:
Return Value From Session