hi,

there , i am coming up with a login page and i am having error when i run the programme. It says 'Invalid attempt to read when no data is present'.

Session("ses_uname") = rdr("FirstName") + " " + rdr("LastName")

Imports System.Data.Sql
Imports System.Data.SqlClient
Imports System.Web
Partial Class _Default
    Inherits System.Web.UI.Page
    Dim str As String = ConfigurationManager.ConnectionStrings("CourierSystemConnectionString").ConnectionString
    Dim con As SqlConnection
    Dim cmd As SqlCommand
    Dim rdr As SqlDataReader
    Dim sql As String
    Dim t As String
    Protected Sub Page_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
    End Sub
    Protected Sub Button1_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles btnlogin.Click
        con = New SqlConnection(str)
        con.Open()
        Dim type As String
        type = ddltype.SelectedValue
        If type = "Customer" Then
            sql = "select * from CusRegis_Table where CusID='" + tuname.Text + "' and password2='" + tupass.Text + "'"

        Else
            sql = "select * from StaffRegis_Table where StaffID='" + tuname.Text + "' and Password='" + tupass.Text + "'"
        End If
        cmd = New SqlCommand(sql, con)
        rdr = cmd.ExecuteReader

        If rdr.HasRows Then
            If ddltype.SelectedValue = "Customer" Then
                Session("ses_dname") = rdr("CusFName") + " " + rdr("CusLName")
                Session("ses_uid") = rdr("Cusid")
                Response.Redirect("Home1.aspx")
                'ElseIf 
                '   ddltype.SelectedValue = "Delivery Boy" Then
                '  Session("ses_dname") = rdr("FirstName") + " " + rdr("Lastname")
                ' Session("ses_uid") = rdr("staffid")
                'Session("ses_utype") = rdr("Designation")
                'Response.Redirect("DeliveryBoyDirection.aspx")
            Else
                ddltype.SelectedValue = "DeliveryBoy"
                [B]Session("ses_uname") = rdr("FirstName") + " " + rdr("LastName")[/B]                Session("ses_uid") = rdr("staffid")
                Session("ses_utype") = rdr("Designation")
                Response.Redirect("DeliveryBoyDirection.aspx")

            End If
        End If
    End Sub
End Class

Include the read method first.

[B]rdr.read();[/B]
if(rdr.hasrows)
..............................

thank you for replying.
I am not sure where to key in the read method

Just change 'If rdr.HasRows' to 'If rdr.Read()'

Therefore your code should be as follows

If rdr.Read() Then
            If ddltype.SelectedValue = "Customer" Then
                Session("ses_dname") = rdr("CusFName") + " " + rdr("CusLName")
                Session("ses_uid") = rdr("Cusid")
                Response.Redirect("Home1.aspx")
                'ElseIf 
                '   ddltype.SelectedValue = "Delivery Boy" Then
                '  Session("ses_dname") = rdr("FirstName") + " " + rdr("Lastname")
                ' Session("ses_uid") = rdr("staffid")
                'Session("ses_utype") = rdr("Designation")
                'Response.Redirect("DeliveryBoyDirection.aspx")
            Else
                ddltype.SelectedValue = "DeliveryBoy"
                Session("ses_uname") = rdr("FirstName") + " " + rdr("LastName")                Session("ses_uid") = rdr("staffid")
                Session("ses_utype") = rdr("Designation")
                Response.Redirect("DeliveryBoyDirection.aspx")

            End If
        End If

i think you are VB.net...but i'm the C# guy...

i guess you are missing toSting() function which is required...

in your code instead storing the string,you are storing the reader object...

string finaltext = rdr["FirstName"].tostring() + "" + rdr["LastName"].toString();

Session.add("ses_uname",) = rdr("FirstName") + " " + rdr("LastName")

hope it helps...and if i'm wrong please let me know...

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