I did try it plain but though the cbo showed blank the id was written to it by my ReplaceID() which is called in the keypress(), maybe it is me but I was not able to shift the replaceid() call to lostfocus().

>That's not what I meant. With Ctrl+0 you don't need to capture and replace with a NULL. Ctrl+0 does it. IOW no code needed (like Ctrl+T,Y in browse or Ctrl+A,C,V,X).
>Cetin
>
>>Thanks and as I use KeyPress I can capture the keystroke and replace with a null.
>>
>>I have also put up a thread about validations through tables for critical analysis, if you are interested will you go through it for me.
>>
>>Thanks a lot.
>>
>>>From VFP help :
>>>"Also, CTRL+0 is supported in ON KEY LABEL in Visual FoxPro, allowing you to redefine the key combination used to enter a null value into a field."
>>>
>>>"Using NULL in Values and Expressions
>>>In Visual FoxPro, you assign the null value programmatically with the .NULL. token or interactively with CTRL+0 in a field. "
>>>
>>>Cetin
>>>
>>>
>>>>Thanks I just tried it and in my auto complete combo where I replace the ID as soon as I keypress, failed but this is any idea I will work on as it is, I hope, default VFP behaviour.
>>>>
>>>>>>Hi all
>>>>>>
>>>>>>I have this form with a cbo. This cbo is allowed to remain empty. If the user moves forward without modifying then alls well.
>>>>>>
>>>>>>Now supposing the user makes a selection and then he doesn't want it, how can he undo his selection. This cbo is connected to a lookup master database, as soon as the selection is made the FK in this table is updated with the PK from the lookup master.
>>>>>>
>>>>>>Except reverting changes is there any solution. Please advise.
>>>>>
>>>>>As an addition to Alex and David, Ctrl+0 'zero' unselects.
>>>>>Cetin