How to get all rows for particular column from database in combobox in VB.net?

Question

Here I am trying to get column from database in combo box.
The code below causes combo box to have System.Data.DataViewManagerListItemTypeDescriptor in the combo box.
What I'm I missing in my code?

Imports System.Data
Imports System.Data.OleDb

Public Class Sales
    Private Const s As String = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=C:\Users\HOME\Desktop\Project\company\company\login.mdb"
    Public conn As OleDbConnection
    Public adapt As OleDbDataAdapter
    Public ds As DataSet
    Public tables As DataTableCollection
    Public table As DataTable
    Public rows As DataRowCollection
    Public row As DataRow
    Public cols As DataColumnCollection
    Public col As DataColumn
    Public sql As String
    Public isql, usql, dsql As String
    Public icmd, ucmd, dcmd As OleDbCommand
    Public p As OleDbParameter

    Private Sub Sales_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
        'TODO: This line of code loads data into the 'LoginDataSet1.Login' table. You can move, or remove it, as needed.
        Me.LoginTableAdapter.Fill(Me.LoginDataSet1.Login)
        Try
            sql = "select cust_ID from Customer"
            conn = New OleDbConnection(s)
            adapt = New OleDbDataAdapter(sql, conn)
            ds = New DataSet
            conn.Open()

            adapt.Fill(ds, "ABC")
            ComboBox1.DataSource = ds
            ComboBox1.DisplayMember = "cust_ID"
            ComboBox1.ValueMember = "cust_ID"


            conn.Close()

        Catch ex As Exception

        End Try
    End Sub
End Class

Answer 1

A DataSet contains DataTables, so you want

Dim connStr = "Data Source=.\SQLEXPRESS;Initial Catalog=testing;Integrated Security=true;"
Dim sql = "SELECT str FROM testTable"
Dim da = New SqlDataAdapter(sql, connStr)
Dim ds = New DataSet
da.Fill(ds)
ComboBox1.DataSource = ds.Tables(0)
ComboBox1.DisplayMember = "str"
ComboBox1.ValueMember = "str"

but it is simpler to go straight for a DataTable:

Dim connStr = "Data Source=.\SQLEXPRESS;Initial Catalog=testing;Integrated Security=true;"
Dim sql = "SELECT str FROM testTable"
Dim da = New SqlDataAdapter(sql, connStr)
Dim dt = New DataTable
da.Fill(dt)
ComboBox1.DataSource = dt
ComboBox1.DisplayMember = "str"
ComboBox1.ValueMember = "str"

Of course, you'll be using the OleDbWhatever equivalents of the SqlWhatever commands I used.