Mysql 如何更快地加载vb.net组合框

我是Vb.net新手，我使用此代码从Mysql数据库加载组合框。 效果很好，但很慢

是否有任何方法可以在一个查询中执行所有这些操作并加载所有Comboboxs，或者有其他方法可以更快地执行此任务

    AbrirDB()
    comandomysql.CommandText = "select distinct TblMarcas.marca from TblMarcas order by marca"
    Try
        Lector = comandomysql.ExecuteReader
        Lector.Read()
        .cbom.Properties.Items.Clear()
        If Lector.HasRows Then
            .cbom.Properties.Items.Add(Lector.Item("marca"))
            Do While Lector.Read
                .cbom.Properties.Items.Add(Lector.Item("marca"))
            Loop
        Else
        End If
    Catch ex As Exception
        DevExpress.XtraEditors.XtraMessageBox.Show(Err.Number & Err.Description)
        If conexion.State = ConnectionState.Open Then conexion.Close()
    End Try
    CerrarDb()




    'CARGO  Categorias a treelist
    AbrirDB()
    comandomysql.CommandText = "select distinct TblCategorias.categoria from TblCategorias order by categoria ASC"
    Try
        Lector = comandomysql.ExecuteReader
        Lector.Read()
        .cboc.Properties.Items.Clear()
        If Lector.HasRows Then
            .cboc.Properties.Items.Add(Lector.Item("categoria"))
            Do While Lector.Read
                .cbocategoria.Properties.Items.Add(Lector.Item("categoria"))
            Loop
        Else

        End If

    Catch ex As Exception
        DevExpress.XtraEditors.XtraMessageBox.Show(Err.Number & Err.Description)
        If conexion.State = ConnectionState.Open Then conexion.Close()
    End Try
    CerrarDb()


    'CARGO Subcategorias
    AbrirDB()
    comandomysql.CommandText = "select distinct TblSubcategorias.subcategoria from TblSubcategorias order by subcategoria ASC"
    Try
        Lector = comandomysql.ExecuteReader
        Lector.Read()
        .cbos.Properties.Items.Clear()
        If Lector.HasRows Then
            .cbos.Properties.Items.Add(Lector.Item("subcategoria"))
            Do While Lector.Read
                .cbos.Properties.Items.Add(Lector.Item("subcategoria"))
            Loop

        End If

    Catch ex As Exception
        DevExpress.XtraEditors.XtraMessageBox.Show(Err.Number & Err.Description)
        If conexion.State = ConnectionState.Open Then conexion.Close()
    End Try
    CerrarDb()

任何帮助都将不胜感激。

请尝试：
myCombo.SuspendLayout（）
将表格变暗为新的DataTable（）
表.加载（MyDataReader）
myCombo.DataSource=表
myCombo.DisplayMember=“column1”

---

myCombo.ResumeLayout（）

填充一个数据表并将CBO.DataSource绑定到它例如：我尝试了一下，但比使用While和Loop加载要慢