Delphi语法中的循环WHILE..DO和REPEAT..UNTIL

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Edit1: TEdit;
    Button1: TButton;
    Button2: TButton;
    procedure Button1Click(Sender: TObject);
    procedure Button2Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var odds,sum:integer;
begin
sum:=0;
odds:=1;
while odds<=  strtoint(Edit1.Text) do
begin
  sum:=sum+odds;
  odds:=odds+2;
end;
Showmessage(inttostr(sum));
end;

procedure TForm1.Button2Click(Sender: TObject);
var odds,sum:integer;
begin
sum:=0;
odds:=1;
Repeat
  sum:=sum+odds;
  odds:=odds+2;
until odds > strtoint(Edit1.Text);
Showmessage(inttostr(sum));
end;

end.

while..do是条件先行，repeat..until是条件后行,所以repeat..until的语法段里面至少要运行一次，Delphi给人的感觉学习起来没什么难度，主要还是有别的语言的基础吧，也主要是自己做多了面向对象的开发，总觉得Delphi7的IDE差微软的DOTNET级别的IDE远多了，用起来不是很顺手。

转载于:https://www.cnblogs.com/lify0407/archive/2007/07/20/825701.html