Title: numeric editbox
Every developer needs any editbox where end-user can enter only numbers.
This is very popular task and you may find a lot of such topics in the
public forums/newsgroups.
But most answers in forums are incorrect as I see, because they suggest
to write some code in OnKeyPress handler and to check there what is a
character pressed.
I say that this code is an incorrect because user could enter any
alfa-characters there anyway (via clipboard, for example).
Today I want to post a simple code that allow to solve this task without
any problems.
Microsoft have the ES_NUMBER style for any editbox. So all what you need
is to send this flag for your editbox:
var
defstyle: dWord;
begin
defstyle := GetWindowLong(Edit1.Handle, GWL_STYLE);
SetWindowLong(Edit1.Handle, GWL_STYLE, defstyle or ES_NUMBER)
end;
If you also want to have a right aligned number, send additionally the
ES_RIGHT flag there
It's all - only numeric characters are possible and this is controled on
OS level. Hope that you'll like this tip...