Object reference not set to an instance of an object.

[primagic]

I am getting the following error on line 26. can someone tell me where I am going wrong. Its a radiobuttonlist I am trying to get the value from

Line 26:         cmdInsert.Parameters.AddWithValue("@Gender", rdoGender.SelectedItem.Value)

Thanks

Imports System.Data.SqlClient
Imports System.Data
Imports System.Web.UI.WebControls.RadioButtonList

Partial Class register
    Inherits System.Web.UI.Page
    





    Protected Sub btnSubmit_Click(ByVal sender As Object, ByVal e As System.EventArgs)
        Dim conTIBMembers As SqlConnection
        Dim strInsert As String
        Dim cmdInsert As SqlCommand

        Dim rdoGender As System.Web.UI.WebControls.RadioButtonList = Nothing

        conTIBMembers = New SqlConnection("Server=(local);UID=sa;PWD=admin2010;database=TIB")
        strInsert = "Insert dbo.Members (Firstname, Surname, Nationality, Gender, DateofBirth, EmailAddress, Password, MailingList) Values (@Firstname, @Surname, @Nationality, @Gender, @DateofBirth,  @EmailAddress, @Password, @MailingList)"
        cmdInsert = New SqlCommand(strInsert, conTIBMembers)
        cmdInsert.Parameters.AddWithValue("@Firstname", txtFirstname.Text)
        cmdInsert.Parameters.AddWithValue("@Surname", txtSurname.Text)
        cmdInsert.Parameters.AddWithValue("@Nationality", cboNationality.SelectedItem.Text)
        cmdInsert.Parameters.AddWithValue("@Gender", rdoGender.SelectedItem.Value)
        cmdInsert.Parameters.AddWithValue("@DateofBirth", txtDateofBirth.Text)
        cmdInsert.Parameters.AddWithValue("@EmailAddress", txtEmail.Text)
        cmdInsert.Parameters.AddWithValue("@Password", txtPassword.Text)
        cmdInsert.Parameters.AddWithValue("@MailingList", chkMailingList.Checked)
        conTIBMembers.Open()
        cmdInsert.ExecuteNonQuery()
        conTIBMembers.Close()

    End Sub
End Class

 

[ca8msm]

I guess that the SelectedItem property is null, i.e. nothing has been selected at the point of you trying to access it.

Mark,

Darlington Web Design[tab]|[tab]Experts, Information, Ideas & Knowledge[tab]|[tab]ASP.NET Tips & Tricks

 

[jbenson001]

What is the error message?

 

[SimonSellick]

There does not appear to be anything to initialise rdoGender between

Dim rdoGender As System.Web.UI.WebControls.RadioButtonList = Nothing

and your reference to the SelectedItem property. I can't remember what Nothing means in .Net, but I doubt if it has a SelectedItem property.

HTH
Simon

 

[jbenson001]

Why would you define a radiobuttonlist and then set it to nothing? You have to use NEW to initalize a control. And if you do it your way, you still have to add it to the control collection of the page. You probably just want to drop the control on the page and let .net define and initalize it, then you can get the value easily.

 

[ca8msm]

I can't remember what Nothing means in .Net, but I doubt if it has a SelectedItem property.

Nothing just means a null object, so in this case the rdoGender object will still have a type of RadioButtonList and therefore a SelectedItem property (but one that is null so you can't access it's Value property).

As you point out though, the OP hasn't set the SelectedItem anywhere prior to using it.

Mark,

Darlington Web Design[tab]|[tab]Experts, Information, Ideas & Knowledge[tab]|[tab]ASP.NET Tips & Tricks

 

[primagic]

Thanks for all your replies. I managed to solve it by removing the line

Dim rdoGender As System.Web.UI.WebControls.RadioButtonList = Nothing

And changing

cmdInsert.Parameters.AddWithValue("@Gender", rdoGender.SelectedItem.Value)

to

cmdInsert.Parameters.AddWithValue("@Gender", rdoGender.SelectedValue)