Hello Alexander.

when the textbox is entered with the mouse it must be only (!) selected if the mouse click succeeded left to the filled part of a textbox. The background is: if the user clicks on the existing text - he must be able to edit it at once, otherwise the whole textbox must be selected and overwritten, but for the case when the allignment is left and the user clicks to the right of it and is probably going to add some text.

I guess I took my stupid pills today because I really do not understand what you are trying to do. Can you explain this to me in a way that I am able to understand < s > ?

But no matter which Code - it works only AFTER the focus is set, not when you get into the textbox from some other place.

I am not sure what you mean by this. Of course it only works after you set focus to the textbox. Where to you expect this to happen < s > ?

I wonder, at what moment is the SelStart really set?

SelStart is set in the GotFocus().

The same textbox without anything in FORMAT or INPUTMASK has LEN(This.text) equal 16. What does it all mean?

Beats the heck out of me < s >. That is why I used LEN( ALLTRIM( TRANSFORM( This.Value ) ). In my little test form, that worked better than LEN( This.Text ).