修饰符（整数篇）

unit Unit4;

interface

uses
  Winapi.Windows, Winapi.Messages, System.SysUtils, System.Variants, System.Classes, Vcl.Graphics,
  Vcl.Controls, Vcl.Forms, Vcl.Dialogs, Vcl.StdCtrls;

type
  TForm4 = class(TForm)
    Button1: TButton;
    Memo1: TMemo;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form4: TForm4;

implementation

{$R *.dfm}

procedure integer1(a: Integer);
begin
  a := a + 1;
end;

procedure integer2(const a: Integer);
begin
  //什么都不做
  a.ToString;
end;

procedure integer3(var a: Integer);
begin
  a := a + 1;
end;

procedure integer4(out a: Integer);
begin
  a := a + 1;
end;

procedure Int641(a: Int64);
begin
  a := a + 1;
end;

procedure Int642(const a: Int64);
begin
  //什么都不做
  a.ToString;
end;

procedure Int643(var a: Int64);
begin
  a := a + 1;
end;

procedure Int644(out a: Int64);
begin
  a := a + 1;
end;

procedure TForm4.Button1Click(Sender: TObject);
var
  i: Integer;
  i2: Int64;
begin
  i := 10;
  i2 := 10;
  Integer1(i);
  Memo1.Lines.Add(i.ToString);
end;

end.

首先Integer1---无修饰符

=========================================================================

 integer2---const

=========================================================================

 integer3---var

=========================================================================

 integer4---out

 经过测试 int64也是如此。

结论：整型 是传值的，就是说 所有的整型要么值复制一份入栈，要么直接用原来的值，与堆无关。