Solved

Moving past VB6 to Visual Studio 2010

Posted on 2010-11-10
6
355 Views
Last Modified: 2012-05-10
I'm finally leaving the VB6 world...have Visual Studio 2010 installed.  I've created a project and dropped some controls on it...just as an exercise, I want to populate my combo box from a command button click event.  Of course I'm getting a runtime error, "ArgumentException was unhandled" on the ComboBox1.DataSource = objReader line.  Do I have to reference something like I would in VB6?  How does it know which field I want to choose for the combo box?   I don't even know if I'm connected to the db.    Will some kind Expert help me take this first step?
Public Class Form1



Private Sub Button1_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button1.Click

      

Dim strSQL As String



strSQL = ""

strSQL = "SELECT * FROM myDB.myOwner.myTable ORDER BY MyField"



'Establish connection and open database connection

Dim objConnection As New SqlClient.SqlConnection("server=mySQLServer;database=myDB;user=myUser;pwd=MyPWD")



'Establish command object

Dim objCommand As New SqlClient.SqlCommand(strSQL, objConnection)



Dim objReader As SqlClient.SqlDataReader



objConnection.Open()



objReader = objCommand.ExecuteReader



ComboBox1.DataSource = objReader



objReader.Close()



objConnection.Close()



End Sub

End Class

Open in new window

0
Comment
Question by:MariaHalt
6 Comments
 
LVL 52

Expert Comment

by:Carl Tawn
ID: 34105890
You can't use a DataReader as the datasource of the ComboBox as it only accepts objects that implement the IList or IListSource interfaces.

You can find a simple example here that uses a DataTable instead:

    http://msdn.microsoft.com/en-us/library/w67sdsex(v=VS.90).aspx

Or you could try this:
   '// you want to be careful about using * in select statements!

   Dim strSQL As String = "SELECT * FROM myDB.myOwner.myTable ORDER BY MyField"



   'Establish connection and open database connection

   Dim objConnection As New SqlClient.SqlConnection("server=mySQLServer;database=myDB;user=myUser;pwd=MyPWD")



   'Establish command object

   Dim objCommand As New SqlClient.SqlCommand(strSQL, objConnection)

   Dim adap As New SqlDataAdapter(objCommand, objConnection)



   Dim ds As New DataSet()

   adap.Fill(ds)



   '// tell the combobox which fields to use

   ComboBox1.DisplayMember = "Name of column for text display"

   ComboBox1.ValueMember = "Name of column for underlying value, probably an ID of some kind"



   ComboBox1.DataSource = ds.Tables(0)





End Sub

Open in new window

0
 
LVL 15

Expert Comment

by:x77
ID: 34105952
Windows Form Contros DataReader do´nt support DataReader as DataSource.
You can do it with Web Controls.

For Windows App use a DataTable as DataSource:

Dim Dt as new DataTable
Dt.Load(objReader)
ComboBox1.DataSource =Dt

or

Dim Dt As new DataTable, Da as new SqlClient.SqlDataAdapter(strSQL, objConnection)
Da.Fill(Dt)
ComboBox1.DataSource = Dt

0
 

Author Comment

by:MariaHalt
ID: 34105988
Thanks for the quick reply, I'm getting a different error:  Type 'SqlDataAdapter' is not defined.
0
How to run any project with ease

Manage projects of all sizes how you want. Great for personal to-do lists, project milestones, team priorities and launch plans.
- Combine task lists, docs, spreadsheets, and chat in one
- View and edit from mobile/offline
- Cut down on emails

 
LVL 69

Expert Comment

by:Éric Moreau
ID: 34106029
you can use SqlCient.SqlDataAdapter
0
 

Author Comment

by:MariaHalt
ID: 34106205
Still getting an error:  Type 'SqlCient.SqlDataAdapter' is not defined.


'Dim adap As New SqlDataAdapter(objCommand, objConnection)
Dim adap As New SqlCient.SqlDataAdapter(objCommand, objConnection)
0
 
LVL 52

Accepted Solution

by:
Carl Tawn earned 500 total points
ID: 34106307
You'll need to add the following at the top of your file, if you don't have it already:


     Imports System.Data.SqlClient
0

Featured Post

Top 6 Sources for Identifying Threat Actor TTPs

Understanding your enemy is essential. These six sources will help you identify the most popular threat actor tactics, techniques, and procedures (TTPs).

Join & Write a Comment

This tutorial demonstrates one way to create an application that runs without any Forms but still has a GUI presence via an Icon in the System Tray. The magic lies in Inheriting from the ApplicationContext Class and passing that to Application.Ru…
A while ago, I was working on a Windows Forms application and I needed a special label control with reflection (glass) effect to show some titles in a stylish way. I've always enjoyed working with graphics, but it's never too clever to re-invent …
This video discusses moving either the default database or any database to a new volume.
Illustrator's Shape Builder tool will let you combine shapes visually and interactively. This video shows the Mac version, but the tool works the same way in Windows. To follow along with this video, you can draw your own shapes or download the file…

757 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question

Need Help in Real-Time?

Connect with top rated Experts

23 Experts available now in Live!

Get 1:1 Help Now