Examples Delphi

Question:
How can I test if a given string contains a valid number?
Answer:
Use one of the string to number function inside a try except block,
and test for an exception.
Example:
function IsStrANumber(NumStr : string) : bool;
begin
result := true;
try
StrToInt(NumStr);
except
result := false;
end;
end;
procedure TForm1.Button1Click(Sender: TObject);
begin
if IsStrANumber(Edit1.Text) then
ShowMessage(Edit1.Text) else
ShowMessage('Not a Number');
end;