書本實例3 單選按鈕和複選按鈕

《Delphi 7編程技巧與實例精解》實例3

看了題目以後我先按本身的思路實現了，我是在點擊「顯示」按鍵的時候再一次性檢查控件的屬性，來肯定ShowMessage的內容。
書本給出的程序樣例是在每次用戶點擊控件的時候就更新一次存有message內容的變量，我想這樣應該比較浪費資源吧，不過程序很小，估計沒影響。

姓名、性別、學習成績這些都相對簡單。興趣愛好那裏，創建一個flag變量來肯定是否有選擇。感受寫了好多行把flag設置爲True的代碼，不知道VCL自己有沒有更簡單的函數來提供這個檢驗。

 

unit Unit1;

interface

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

type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    Button1: TButton;
    Edit1: TEdit;
    RadioButton1: TRadioButton;
    RadioButton2: TRadioButton;
    RadioGroup1: TRadioGroup;
    GroupBox1: TGroupBox;
    CheckBox1: TCheckBox;
    CheckBox2: TCheckBox;
    CheckBox3: TCheckBox;
    CheckBox4: TCheckBox;
    CheckBox5: TCheckBox;
    CheckBox6: TCheckBox;
    procedure Button1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}

var
  name,gender,grade,hobbies: String;
  hobbyList: Array of String;


procedure TForm1.Button1Click(Sender: TObject);
var
  msg,hobby: String;
  hobbiesFlag: Boolean;

begin
  //clear
  name := '';
  gender := '';
  grade := '';
  hobbies := '';
  hobbiesFlag := False;

  setLength(hobbyList,6);
  hobbyList[0] :='文學';
  hobbyList[1] :='音樂';
  hobbyList[2] :='棋牌';
  hobbyList[3] :='繪畫';
  hobbyList[4] :='體育';
  hobbyList[5] :='數學';

  //set name
  name := Edit1.Text;

  //set gender
  if RadioButton1 .Checked then
    gender := '男';
  if RadioButton2.Checked then
    gender := '女';

  //set grade
  if RadioGroup1.ItemIndex > -1 then
    case RadioGroup1.ItemIndex of
      0: grade := '優';
      1: grade := '良';
      2: grade := '中';
      3: grade := '差';
    end;

  //set hobbies
  if CheckBox1.Checked then
  begin
    hobbiesFlag := True;
    hobby := hobby + hobbyList[0] + '、';
  end;
  if CheckBox2.Checked then
  begin
    hobbiesFlag := True;
    hobby := hobby + hobbyList[1] + '、';
  end;
  if CheckBox3.Checked then
  begin
    hobbiesFlag := True;
    hobby := hobby + hobbyList[2] + '、';
  end;
  if CheckBox4.Checked then
  begin
    hobbiesFlag := True;
    hobby := hobby + hobbyList[3] + '、';
  end;
  if CheckBox5.Checked then
  begin
    hobbiesFlag := True;
    hobby := hobby + hobbyList[4] + '、';
  end;
  if CheckBox6.Checked then
  begin
    hobbiesFlag := True;
    hobby := hobby + hobbyList[5] + '、';
  end;

  //show message
  if name = '' then
    showMessage('請輸入名字')
  else if gender = '' then
    showMessage('請輸入性別')
  else if grade = '' then
    showMessage('請輸入成績')
  else if hobbiesFlag = False then
    showMessage('請選擇愛好')
  else
  begin
    msg := '您的姓名是：'+name+ #13#10 +
           '您的性別是：'+gender+ #13#10 +
           '您的學習成績是：'+grade+ #13#10 +
           '您的愛好是：' + hobby;
    msg[msg.Length] := #13;
    msg := msg + #10;
    ShowMessage(msg);

end;
end;
end.

運行結果：