1、Delphi 变量的定义及命名

1、变量的定义

      VAR

            变量名：变量类型；

     例：var

             sex:string;      (冒号与分号都是英文输入)

   同类型的多个变量的定义

        VAR

            变量名1，变量名2，变量名3：变量类型；

      例：var

             sex,taste,grade:string;

2、变量的命名

     （1）首字符必须是英文。

     （2）只能由英文、数字和下划线组成。

 

例：制作单选按钮和复选按钮

unit Unit1;
interface
uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, ExtCtrls;
type
  TForm1 = class(TForm)
    Label1: TLabel;
    Label2: TLabel;
    Label3: TLabel;
    RadioButton1: TRadioButton;
    RadioButton2: TRadioButton;
    GroupBox1: TGroupBox;
    CheckBox1: TCheckBox;
    CheckBox2: TCheckBox;
    CheckBox3: TCheckBox;
    CheckBox4: TCheckBox;
    CheckBox5: TCheckBox;
    CheckBox6: TCheckBox;
    RadioGroup1: TRadioGroup;
    Button1: TButton;
    Edit1: TEdit;
    procedure Button1Click(Sender: TObject);
    procedure RadioButton2Click(Sender: TObject);
    procedure CheckBox1Click(Sender: TObject);
    procedure RadioGroup1Click(Sender: TObject);
  private
    { Private declarations }
  public
    { Public declarations }
  end;
var
  Form1: TForm1;
  sex,taste,grade:string;
implementation
{$R *.dfm}
procedure TForm1.Button1Click(Sender: TObject);
begin
 showmessage('您的姓名是：'+edit1.Text+#13#10+
              '你的性别是：'+sex+#13#10+
              '你的爱好是：'+taste+#13#10+
              '你的成绩是：'+grade );
end;
procedure TForm1.RadioButton2Click(Sender: TObject);
begin
if  radiobutton2.Checked  then
         sex:='男'
  else if  radiobutton1.Checked  then
         sex:='女' ;
end;
procedure TForm1.CheckBox1Click(Sender: TObject);
begin
       taste:='';
       if checkbox1.Checked then
          if taste='' then
            taste:=checkbox1.Caption
            else
            taste:=taste+'、'+checkbox1.Caption ;
       if checkbox2.Checked then
          if taste='' then
            taste:=checkbox2.Caption
            else
            taste:=taste+'、'+checkbox2.Caption ;
       if checkbox3.Checked then
          if taste='' then
            taste:=checkbox3.Caption
            else
            taste:=taste+'、'+checkbox3.Caption ;
       if checkbox4.Checked then
          if taste='' then
            taste:=checkbox4.Caption
            else
            taste:=taste+'、'+checkbox4.Caption ;
        if checkbox5.Checked then
          if taste='' then
            taste:=checkbox5.Caption
            else
            taste:=taste+'、'+checkbox5.Caption ;
        if checkbox6.Checked then
          if taste='' then
            taste:=checkbox6.Caption
            else
            taste:=taste+'、'+checkbox6.Caption ;
end;
procedure TForm1.RadioGroup1Click(Sender: TObject); 
begin
     case radiogroup1.ItemIndex of
      0:grade:='优';
      1:grade:='良';
      2:grade:='中';
      3:grade:='差';
      end;
end;
end.