How to insert NULL into database if form field is empty

Question

I have a form and stored procedure that inserts the data from the form. It works fine except that if a field isn\'t filled in it doesn\'t insert a NULL into SQL

Answer 1

why you even set it if it is null?

        If pd_first_name.Text <> "" Then
          frmFirstName = pd_first_name.Text
          firstname = New SqlParameter()
          firstname.ParameterName = "@firstname"
          firstname.SqlDbType = SqlDbType.NVarChar
          firstname.Size = 50
          firstname.Direction = ParameterDirection.Input
          firstname.Value = frmFirstName
        End If