Check format of input string in text box

[joesph]

I have a text box on a form in my application which I want to check the format of. ie. the text box allows users to input a numeric value which can be either + or - depending on whether or not it is preceeded by a +/- symbol does anyone know how to check that the inputted value is only a numeric value preceeded by +/-
Thanks

 

[McMerfy]

procedure TForm1.Edit2KeyPress(Sender: TObject; var Key: Char);
begin
  if (not (Key in ['+', '-', '0'..'9']))then
   Key := #0;
end;

Cheers

--- markus

 

[Ronin441]

Good answer.

Also take a look at TMaskEdit. For integer numeric, you'd want a mask something like '

#999999999;0;

' or '

#000000000;0;

'.

Also also for integer numeric, take a look at TSpinEdit, on the Samples tab. -- Doug Burbidge mailto:dougburbidge@yahoo.com

http://home.iprimus.com.au/dougburbidge/

 

[sggaunt]

If you want to test whatever was entered afterwards.
you can use this sort of construct
try
n := strtoint(edit1.text)
except
showmessage('Not a Number');
end;

Niether this or Markus answer will allow floating point numbers to be entered. But you could add '.' to the test[set].

Use the val() procedure to validate floating point input

Delphi also provides a formated edit box 'MaskEdit'
I think you can set this up to accept float formats.

Steve