access value by Property

[question]

Here is the sample code please

Code:

unit Unit1; 
{

interface

uses
  Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs;

type
  TForm1 = class(TForm)
    
  private
    FNewID : Integer;    
  public
    property NewID : Integer read FNewID;
    Person (ID : Integer);
  end;

var
  Form1: TForm1;
  
implementation


{$R *.DFM}
{$R common.res}

procedure  TForm1.Person (ID : Integer);
begin
//here i get the value of ID after query from Database
//for example I have got ID=20;
end;

procedure TForm1.btnOkClick(Sender: TObject);
begin
if True then //after check the condition, i wanna call
Form1.Person (ID); // here how can i initialize ID so that i get the value 20
end;

end.

[DeddyH]

You can use a function instead of a procedure, or you can pass the parameter by reference.

Delphi-Quellcode:

function TForm1.Person: integer;
begin
  Result := <ID retrieved by query>;
end;

procedure TForm1.Person(out ID: integer);
begin
  ID := <ID retrieved by query>;
end;

If you want to access the parameter inside the procedure, use "var" instead of "out".

[question]

Thanks for suggestion

but how can i initialize the ID:Integer in event handler, becasue in event handler i cannot add any parameter, for example

Code:

procedure TForm1.Button1click(Sender: Tobject);// i cannot set anyother parameter,then delphi compiler automatic delete the adding parameter
begin
 //here i need the value of ID,which is for example 20, if i declare var ID: Integer here then it give me the value 0
end;
end.

[DeddyH]

Delphi-Quellcode:

procedure TForm1.Button1click(Sender: Tobject);
var
  ID: integer;
begin
  Person(ID); //Now ID should have the value which is retrieved by your query
end;

[question]

I have tried it but then i found the value of id

Code:

Procedure TForm1.Person(ID : Integer);
begin
//here the query excuted with a value of ID which comes from another procedure
//therefore to use the function its a lot more change in whole code
// i think in my situation pass parameter by reference will be best way
end;

it would be kind of you, if you give me a small example concerning my situation in order to pass the parameter by refrence from Procedure TForm1.Person(ID : Integer); to Procedure TForm1.Button1Click(Sender: TObject);

[DeddyH]

The OnClick-Event is a TNotifyEvent, you cannot change this. I still don' t know what you want to do exactly, maybe a little explanation could be helpful.