Olá Rune,
Procedimento C# para combobox normal:
public static void ClearCombo(string FormUID, string ItemUID)
{
int count;
try
{
if ( ((SAPbouiCOM.ComboBox)(SBO_Application.Forms.Item(FormUID).Items.Item(ItemUID))).ValidValues.Count > 0 )
{
count = ((SAPbouiCOM.ComboBox)(SBO_Application.Forms.Item(FormUID).Items.Item(ItemUID))).ValidValues.Count;
for (int i = 1; i <= count; i++)
{
((SAPbouiCOM.ComboBox)(SBO_Application.Forms.Item(FormUID).Items.Item(ItemUID)).ValidValues.Remove(count - i - 0, SAPbouiCOM.BoSearchKey.psk_Index);
}
((SAPbouiCOM.ComboBox)(SBO_Application.Forms.Item(FormUID).Items.Item(ItemUID)).ValidValues.Add("0", " ");
((SAPbouiCOM.ComboBox)(SBO_Application.Forms.Item(FormUID).Items.Item(ItemUID)).