# Structure

This article describes the inner structure and organization of the elements which build the **RadMultiColumnComboBox** control.

> caption Figure 1: RadMultiColumnComboBox's Elements Hierarchy

![WinForms RadMultiColumnComboBox Elements Hierarchy](https://www.telerik.com/products/winforms/documentation/assets/a044dd3adb22d88513814784ceba39d3/multicolumncombobox-structure001.png)

> caption Figure 2: MultiColumnComboPopupForm's Elements Hierarchy

![WinForms RadMultiColumnComboBox MultiColumnComboPopupForm's Elements Hierarchy](https://www.telerik.com/products/winforms/documentation/assets/59ddc607ae025d1ac8f607ba7292c600/multicolumncombobox-structure002.png)

> caption Figure 3: RadMultiColumnComboBox Visual Structure

![WinForms RadMultiColumnComboBox RadMultiColumnComboBox Visual Structure](https://www.telerik.com/products/winforms/documentation/assets/82c8a37c21398427902c271571b887bc/multicolumncombobox-structure003.png)

1\. **RadMultiColumnComboBoxelement**:\
    1. 1. **RadTextBoxElement**: represents the editor element.\
    1. 2. **RadArrowButtonElement**: represents the arrow primitive.\
2\. **MultiColumnComboPopupForm**:\
  2.1. **DockLayoutPanel**:\
    2.1.1. **GridViewHostItem**: hosts the pop up **RadGridView**.\
    2.1.2. **SizeGripElement**: represents the resizing grip.

The drop-down element is an object of type **MultiColumnComboBoxElement**. Use this element to set the [drop-down style](https://www.telerik.com/products/winforms/documentation/controls/dropdown-listcontrol-and-checkeddropdownlist/dropdownlist/dropdownstyle), [animation](https://www.telerik.com/products/winforms/documentation/controls/dropdown-listcontrol-and-checkeddropdownlist/dropdownlist/animation-effects) and [sizing](https://www.telerik.com/products/winforms/documentation/controls/dropdown-listcontrol-and-checkeddropdownlist/dropdownlist/dropdown-resizing) as you would do for the regular combo box.  

The **EditorControl** property of the **RadMultiColumnComboBoxElement** gives you a reference to the **RadGridView** control. Using that reference you can obtain the **RadGridView** object and work as with normal **RadGridView** control. Refer to the [RadGridView documentation](https://www.telerik.com/products/winforms/documentation/controls/gridview/overview) for additional information on **RadGridView**.

## See Also

* [RadControlSpy](https://www.telerik.com/products/winforms/documentation/tools/controlspy/controlspy)