multiple SQL queries stored as vb.net variable - sql

Question

I know there are a few other posts about putting sql results into a vb.net variable but I just couldn't wrap my head around how they did it and how I could do it in my project.
So what I'm trying to do is query my database for 4 different values and then display each value in a certain part of the form. I was going to store the each value into a variable and then do an textbox1.text = i
Updated code for 10/5/2014
Private Sub LBmembers_SelectedIndexChanged(sender As Object, e As EventArgs) Handles LBmembers.SelectedIndexChanged
Dim i As String = LBmembers.SelectedItem
Dim dbProvider = "PROVIDER=Microsoft.Jet.OLEDB.4.0;"
Dim dbSource = "Data Source= C:\members.mdb "
Dim SqlQuery As String = "SELECT StartTime, EndTime, ShipCode, CycleTime, WorkPercent, Share FROM tblMembers WHERE Member = #ID;"
Using con = New OleDb.OleDbConnection(dbProvider & dbSource)
Using cmd = New OleDb.OleDbCommand(SqlQuery, con)
con.Open()
cmd.Parameters.AddWithValue("#ID", OleDb.OleDbType.VarWChar).Value = i
Using reader = cmd.ExecuteReader()
If reader.Read() Then
TBtimestart.Text = reader.ToString(0)
TBtimeend.Text = reader.ToString(1)
Dim j = Convert.ToInt32(reader.ToString(2))
TBtimecycle.Text = reader.GetInt32(3).ToString
TBmemberpercent.Text = reader.GetInt32(4)
TBmembershare.Text = reader.GetInt32(5)
If j = 1 Then
RBpro.Checked = True
ElseIf j = 2 Then
RBret.Checked = True
ElseIf j = 3 Then
RBcov.Checked = True
ElseIf j = 4 Then
RBskiff.Checked = True
ElseIf j = 5 Then
RBmack.Checked = True
ElseIf j = 6 Then
RBhulk.Checked = True
Else
RBpro.Checked = False
RBret.Checked = False
RBcov.Checked = False
RBskiff.Checked = False
RBmack.Checked = False
RBhulk.Checked = False
Exit Sub
End If
End If
End Using
con.Close()
End Using
End Using
End Sub
The exception
InvalidCastException was unhandled Specified cast is not valid.
Pops up on the line TBtimecycle.text = reader.GetInt32(3).ToString
The reader is also reading "System.Data.OleDb.OleDbDataReader" when I insert the test code "TBgrossisk.Text = reader.ToString()" into the using statement

Answer 1

If you look carefully to the syntax of the SELECT statement you will see that you can request any column of the table with just one query.
Private Sub ListBox1_SelectedIndexChanged(sender As Object, e As EventArgs) Handles LBmembers.SelectedIndexChanged
if string.IsNullOrWitheSpace(ListBox1.SelectedItem.ToString()) Then
MessageBox.Show("Select an item from the Listbox")
End If
Dim member As String = ListBox1.SelectedItem
Dim dbProvider = "PROVIDER=Microsoft.Jet.OLEDB.4.0;"
Dim dbSource = "Data Source= C:\members.mdb "
Dim SqlQuery As String = "SELECT StartTime, EndTime, ShipCode, CycleTime " & _
"FROM tblMembers WHERE Member = #ID;"
Using con = New OleDb.OleDbConnection(dbProvider & dbSource)
Using cmd = New OleDb.OleDbCommand(SqlQuery, con)
con.Open()
cmd.Parameters.AddWithValue("#ID", OleDb.OleDbType.VarWChar).Value = member
Using reader = cmd.ExecuteReader
if reader.Read() Then
TextBox1.Text = reader.GetString(0)
TextBox2.Text = reader.GetString(1)
Dim j = reader.GetInt32(2)
If j = 1 Then
Radio1.Checked = True
ElseIf j = 2 Then
Radio2.Checked = True
ElseIf j = 3 Then
Radio3.Checked = True
ElseIf j = 4 Then
Radio4.Checked = True
ElseIf j = 5 Then
Radio5.Checked = True
ElseIf j = 6 Then
Radio6.Checked = True
Else
Exit Sub
End If
TextBox4.Text = reader.GetInt32(3).ToString()
Else
MessageBox.Show("The search for '" & member & "' doesn't find any data")
End If
End Using
End Using
End Using
End Sub
Instead of using ExecuteScalar that returns just the first column of the first row retrieved you could use an OleDbDataReader returned by the method ExecuteReader. This object allows to access the various column in the current record using an index (or the column name). Read more about OleDbDataReader in MSDN