Hallo,
trifft das vielleicht bei Dir zu?
Zitat von
Delphi Hilfe:
property OnChange: TNotifyEvent;
Description
Write an OnChange event handler to take specific action immediately after the text of the combo box changes. This event occurs when the user types a new value directly into the edit region, or when the user selects a new item from the drop-down list. The Text property gives the new value.
Note: The OnChange event does not occur when Style is set to csDropDownList. Use OnSelect instead.
Note: OnChange only occurs in response to user actions. Changing the Text property programmatically does not trigger an OnChange event.
Grüße
Klaus