lo puedes hacer de la siguiente forma:
esto es para winforms....
Código:
dim cnn As SqlConnection
dim cadenacon string = "mi cadena de conexion"
cnn= New SqlConnection
cnn.ConnectionString = cadenacon
cnn.Open()
dim sSQL as string = " select * from tabla "
Dim oDataSet As DataSet = New DataSet
Dim oDataAdapter As SqlDataAdapter = New SqlDataAdapter
Dim oCommand As SqlCommand = New SqlCommand
oCommand.Connection = cnn
oCommand.CommandText = sSQL
oCommand.CommandTimeout = 120
oDataAdapter.SelectCommand = oCommand
oDataAdapter.Fill(oDataSet, "nombre de mi tabla")
With combobox1
.DataSource = oDataSet.Tables("nombre de mi tabla")
.DisplayMember = "campo_nombre"
.ValueMember = "id_campo"
End With
suerte---Miguel--in---