Using CreateDataReader to get a value from a field

microsoft.public.dotnet.framework.adonet

30 Jul 2006 9:33 AM

jonefer

I have a tried and true method for grabbing a value in a field based on a
parameter. But I would like to use the CreateDataReader method, or any other
efficient method for user with the graphical dataset designer objects created.

I have two examples below, The first is Getting a provider Name from a
table, based on the ProvID which returns a string. This is code created
using no graphical objects or wizard.

The second is Getting an employee name, based on an ID called NUID. I
wanted to use CreateDataReader, because the objects that I'm working with ARE
generated with the graphical objects in the DataSet designer. For example, I
created a stored procedure using the TableAdapter in the dataset designer.
I've been trying to construct the same method as the working one, using these
graphical (or 'strongly typed?' not sure if this is the term) objects, but it
isn't quite working.

'working example
Public Shared Function GetProviderName(ByVal ProvID As String) As String
        Dim drProvider As SqlDataReader
        Dim conMembers As SqlConnection =
MembershipDB.GetMembershipConnection()
        Dim cmd As New SqlCommand("SELECT ProviderFullName FROM dbo.PROV
WHERE ProvID = @ProvID", conMembers)
        cmd.CommandType = CommandType.Text
        cmd.Parameters.Add("@ProvID", SqlDbType.NVarChar, 5).Value = ProvID

        conMembers.Open()
        drProvider = cmd.ExecuteReader(CommandBehavior.SingleRow)
        If drProvider.Read Then
            Return IIf(drProvider("ProviderFullName") Is DBNull.Value, "No
Provider", drProvider("ProviderFullName"))
        Else
            Return "No Provider"
        End If
        conMembers.Close()
        conMembers.Dispose()
        conMembers = Nothing
    End Function

'Help with this example
Public Shared Function GetEmployeeNameByNUID(ByVal strNUID As String) As
String
        Dim da As New CIA_DatabaseTableAdapters.CIA_REPORT_CTTableAdapter
        Dim dt As New DataTable
        Dim strEmployee As String

        dt = da.FillEmpNameByNUID(strNUID)
        strEmployee = dt.CreateDataReader("Employee").ToString()

        Return strEmployee

    End Function