unit1.~pas

本光盘是《Delphi 7应用教程》一书的配套光盘

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Edit1: TEdit;
    Label2: TLabel;
    Edit2: TEdit;
    Button1: TButton;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation
var
  r:Integer;    //定义全局变量

{$R *.dfm}
Function ana(var m:Integer):Integer;//注意自定义函数必须在事件代码代码之前
begin
  r:=m mod 10;      //余数赋值给变量r
  ana:=m div 10;    //商再赋值给函数名继续做除法
end;

procedure TForm1.Button1Click(Sender: TObject);
var
  k,s:Integer;
begin
  k:=StrToInt(Edit1.Text);  //字符串转换成整数
  s:=0;                     //变量赋初值
  Repeat
    k:=ana(k);           //调用自定义函数求各位数字
    s:=s+r;              //利用累加求各数字之和
  Until (k=0);
  Edit2.Text:=IntToStr(s);//将各位数字之和显示在编辑框2中
end;

end.